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| Author |
scanning family photos - need settings advice
|
|
|
| I'm about to start the process of scanning hundreds of old family photos. I
don't really know a ton about how this stuff works and would love to have a
few questions answered before I get too far into the project.
My scanner supports up to 1200 DPI. The next step down is 600 DPI. I don't
know which to use. My instinct is go with the higher DPI because we're
going to want to have these pictures forever and the scans may end up being
the only copies we have if something happens to the originals. On the other
hand, the difference in size is substantial: over 26 MB for 1200 DPI and
only 6.5 for 600 DPI. What are the pros and cons of each? Is 1200 DPI
overkill? I have mostly black & white photos to scan, but some are in
color. Should I use the higher setting for just the color photos, both or
neither? Any advice would be much appreciated.
Also, I'm just planning on saving the scans in the jpeg format. Any reason
not to? Should I be using a different file format?
Thanks again for any help you can provide.
| |
| Stephan 2004-05-21, 11:28 pm |
| "Nikko" <nothanks@yourmomma.com> wrote in message
news:6hvrc.4886$be.2792@newsread2.news.pas.earthlink.net...
> I'm about to start the process of scanning hundreds of old family photos.
I
> don't really know a ton about how this stuff works and would love to have
a
> few questions answered before I get too far into the project.
>
> My scanner supports up to 1200 DPI. The next step down is 600 DPI. I
don't
> know which to use. My instinct is go with the higher DPI because we're
> going to want to have these pictures forever and the scans may end up
being
> the only copies we have if something happens to the originals. On the
other
> hand, the difference in size is substantial: over 26 MB for 1200 DPI and
> only 6.5 for 600 DPI. What are the pros and cons of each? Is 1200 DPI
> overkill? I have mostly black & white photos to scan, but some are in
> color. Should I use the higher setting for just the color photos, both or
> neither? Any advice would be much appreciated.
>
> Also, I'm just planning on saving the scans in the jpeg format. Any
reason
> not to? Should I be using a different file format?
>
It all depends at what size you will print
Roughly: original size 300, twice the size 600 since you are going to print
at 300 dpi
Save as JPEG if you know you are not going to edit them much otherwise use
TIF
Remember, CD do not last long, read this before you think you are archiving
your family photos by burning them on CD:
http://tinyurl.com/2mqa7
Stephan
| |
| HIKER4LIFE 2004-05-21, 11:28 pm |
| What does that mean "CD do not last long" Does this mean, even if you don't
use them over and over, they corrupt, or what? I am in the dark about how
long a CD will last....
Thanks,
> It all depends at what size you will print
> Roughly: original size 300, twice the size 600 since you are going to
print
> at 300 dpi
> Save as JPEG if you know you are not going to edit them much otherwise use
> TIF
> Remember, CD do not last long, read this before you think you are
archiving
> your family photos by burning them on CD:
> http://tinyurl.com/2mqa7
>
> Stephan
>
>
| |
| Johan W. Elzenga 2004-05-21, 11:28 pm |
| Nikko <nothanks@yourmomma.com> wrote:
> I'm about to start the process of scanning hundreds of old family photos. I
> don't really know a ton about how this stuff works and would love to have a
> few questions answered before I get too far into the project.
>
> My scanner supports up to 1200 DPI. The next step down is 600 DPI. I don't
> know which to use. My instinct is go with the higher DPI because we're
> going to want to have these pictures forever and the scans may end up being
> the only copies we have if something happens to the originals. On the other
> hand, the difference in size is substantial: over 26 MB for 1200 DPI and
> only 6.5 for 600 DPI. What are the pros and cons of each? Is 1200 DPI
> overkill? I have mostly black & white photos to scan, but some are in
> color. Should I use the higher setting for just the color photos, both or
> neither? Any advice would be much appreciated.
1200 dpi is indeed overkill, because the original will not have more
detail than you can capture with 600 dpi or even less. So if you scan at
1200 dpi, you'll get more pixels, but not more detail.
--
Johan W. Elzenga johan<<at>>johanfoto.nl
Editor / Photographer http://www.johanfoto.nl/
| |
|
| Well, I scanned my photos and saved them to CD-R. Later I decided to
transfer the scans to a DVD+R to save space in my cabinet. Alas about 10%
of the 35 CD-R that I made were either partially or completely unreadable.
None of these CD-Rs are more than 3 years old. That easily consists of not
lasting long.
Jim
"HIKER4LIFE" <HIKER4@CHARTER.NET> wrote in message
news:10at29chfvvml19@corp.supernews.com...
> What does that mean "CD do not last long" Does this mean, even if you
don't
> use them over and over, they corrupt, or what? I am in the dark about how
> long a CD will last....
> Thanks,
>
>
> print
use[color=darkred]
> archiving
>
>
| |
| Ron Hunter 2004-05-21, 11:28 pm |
| Nikko wrote:
> I'm about to start the process of scanning hundreds of old family photos. I
> don't really know a ton about how this stuff works and would love to have a
> few questions answered before I get too far into the project.
>
> My scanner supports up to 1200 DPI. The next step down is 600 DPI. I don't
> know which to use. My instinct is go with the higher DPI because we're
> going to want to have these pictures forever and the scans may end up being
> the only copies we have if something happens to the originals. On the other
> hand, the difference in size is substantial: over 26 MB for 1200 DPI and
> only 6.5 for 600 DPI. What are the pros and cons of each? Is 1200 DPI
> overkill? I have mostly black & white photos to scan, but some are in
> color. Should I use the higher setting for just the color photos, both or
> neither? Any advice would be much appreciated.
>
> Also, I'm just planning on saving the scans in the jpeg format. Any reason
> not to? Should I be using a different file format?
>
> Thanks again for any help you can provide.
>
>
Go here:
www.scantips.com
It will explain why scanning at 600DPI would be a waste of time and disk
space for prints.
| |
| Stephan 2004-05-21, 11:28 pm |
|
"HIKER4LIFE" <HIKER4@CHARTER.NET> wrote in message
news:10at29chfvvml19@corp.supernews.com...
> What does that mean "CD do not last long" Does this mean, even if you
don't
> use them over and over, they corrupt, or what? I am in the dark about how
> long a CD will last....
> Thanks,
That is why I provided a link my friend, click on it!
Stephan
| |
| Stephan 2004-05-21, 11:28 pm |
|
"Stephan" <NoMoreSpam@Thank.you> wrote in message
news:5cxrc.1111$AN1.145@twister.socal.rr.com...
>
> "HIKER4LIFE" <HIKER4@CHARTER.NET> wrote in message
> news:10at29chfvvml19@corp.supernews.com...
> don't
how[color=darkred]
>
> That is why I provided a link my friend, click on it!
>
Sorry I just realized these greedy Britts want a pound from you to read
their old news, cheap bastards!
Anyway, CD are the worse way to store info, they become unreadable faster
than you think sometimes in less than two years.
Buy hard drives for longtime storage.
Stephan
| |
| Erik Muna 2004-05-21, 11:28 pm |
| So how come my audio CD's from the early 90's are still 100% playable
even after a LOT of use over the years? In my opinion, *if* CD's don't work
for two reasons: 1) cheap/crappy blanks and 2) cheap/crappy burners. My
first burner was an HP and it was an early generation. A few months later I
got a much nicer Pioneer but it wouldn't play the CD's I had just burned
with my old drive but they *would* still play in the old drive.
Since the nice new drive and new media I've had no problems archiving
data on CD's. If a hard drive gets moved around, even a little in some
cases, you could lose everything. Anyway, my advice would be to use
multiple formats to store valuable things but CD's work best for me and
maybe I'm in the minority but whatever...
--
Erik Muna
Freelance Web Design & Graphic Arts
www.petfishonline.com ... my online portfolio
ICQ: 13466765
"Stephan" <NoMoreSpam@Thank.you> wrote in message
news:pjxrc.1143$AN1.678@twister.socal.rr.com...
CD are the worse way to store info, they become unreadable faster
> than you think sometimes in less than two years.
> Buy hard drives for longtime storage.
>
> Stephan
>
>
| |
| JohnJ 2004-05-21, 11:28 pm |
| Erik Muna wrote:
> So how come my audio CD's from the early 90's are still 100% playable
> even after a LOT of use over the years? In my opinion, *if* CD's don't work
> for two reasons: 1) cheap/crappy blanks and 2) cheap/crappy burners. My
> first burner was an HP and it was an early generation. A few months later I
> got a much nicer Pioneer but it wouldn't play the CD's I had just burned
> with my old drive but they *would* still play in the old drive.
>
> Since the nice new drive and new media I've had no problems archiving
> data on CD's. If a hard drive gets moved around, even a little in some
> cases, you could lose everything. Anyway, my advice would be to use
> multiple formats to store valuable things but CD's work best for me and
> maybe I'm in the minority but whatever...
WRT manufactured CD's, as long as they are stored correctly, they should
last many years without deterioration. Temperature and humidity can
cause damage to these.
Home burned CD & DVD's are much more of a problem. However if done
properly archiving using CD-R & DVD-R's can last many years as well.
First, a high quality burner and high quality media are important. I
personally use Plextor drives and Verbatim DataLifePlus and Taiyo Yuden
media.
For storage, because the media are dye-based, temperature, humidity,
and light can cause deterioration. After burning I store my archives
in a closet. Burning a second copy and storing in a second location
(another house) is good insurance.
Conclusion, if you use a $25 burner with cheap, low quality media
you are risking all your image files.
| |
| Stephan 2004-05-21, 11:28 pm |
|
"Erik Muna" <petfish@shaw.ca> wrote in message
news:iyxrc.560858$Ig.257987@pd7tw2no...
> So how come my audio CD's from the early 90's are still 100% playable
> even after a LOT of use over the years? In my opinion, *if* CD's don't
work
> for two reasons: 1) cheap/crappy blanks and 2) cheap/crappy burners.
My
> first burner was an HP and it was an early generation. A few months later
I
> got a much nicer Pioneer but it wouldn't play the CD's I had just burned
> with my old drive but they *would* still play in the old drive.
>
> Since the nice new drive and new media I've had no problems archiving
> data on CD's. If a hard drive gets moved around, even a little in some
> cases, you could lose everything. Anyway, my advice would be to use
> multiple formats to store valuable things but CD's work best for me and
> maybe I'm in the minority but whatever...
>
You will always find somebody with a story of an uncle who smoked three
packs a day and lived a hundred years.
That doesn't make smoking any safer for the rest of us.
Store your precious data in CDs if you are too broke to buy hard drives,
your problem.
As you said wisely: whatever
Stephan
| |
|
| In article <6hvrc.4886$be.2792@newsread2.news.pas.earthlink.net>, "Nikko"
<nothanks@yourmomma.com> wrote:
> [...] My instinct is go with the higher DPI because we're
> going to want to have these pictures forever and the scans may end up being
> the only copies we have if something happens to the originals.
> [...]
With respect, digital storge can be risky compared to prints. I strongly
suggest you scan and then print archival copies just in case of an
electronic mishap. The prints are your last resort backup.
Just my two-bits worth.
I see you have plenty of good advice concerning the scaning.
Very best of luck,
jjs
| |
|
| In article <10at29chfvvml19@corp.supernews.com>, "HIKER4LIFE"
<HIKER4@CHARTER.NET> wrote:
> What does that mean "CD do not last long" Does this mean, even if you don't
> use them over and over, they corrupt, or what? I am in the dark about how
> long a CD will last....
The truth is nobody _knows_ how long any particular CDROM will last
because today's CDROMS are, ah, todays! We have no history of current
technology. :)
Twelve years is the best guess for CDROM longevity. It could be much less,
or possibly more. An archival print will last 100 years.
| |
|
| In article <iyxrc.560858$Ig.257987@pd7tw2no>, "Erik Muna"
<petfish@shaw.ca> wrote:
> So how come my audio CD's from the early 90's are still 100% playable
> even after a LOT of use over the years?
The ear is not a camera. Picture files and music files are two entirely
different things. Music can degrade, but picture files (FAPP) just go at
once.
| |
| Richard Alexander 2004-05-22, 4:28 am |
| "Nikko" <nothanks@yourmomma.com> wrote in message news:<6hvrc.4886$be.2792@newsread2.news.pas.earthlink.net>...
> I'm about to start the process of scanning hundreds of old family photos. I
> don't really know a ton about how this stuff works and would love to have a
> few questions answered before I get too far into the project.
I am engaged in the same project for my family photos.
> My scanner supports up to 1200 DPI. The next step down is 600 DPI. I don't
> know which to use. My instinct is go with the higher DPI because we're
> going to want to have these pictures forever and the scans may end up being
> the only copies we have if something happens to the originals.
That is my thinking, too. The pack-rat nature runs in my family. I
hate to lose even a single bit of data.
> On the other
> hand, the difference in size is substantial: over 26 MB for 1200 DPI and
> only 6.5 for 600 DPI.
Yes, indeed! I recently scanned 68 photots that were taken with my
boyhood camera, a Kodak 110. I saved each picture as a TIFF, no
compression, 48-bit color, about 80 MB per photo. I could only fit 50
of my scanned photos on a DVD. Those are the largest scans as a series
that I have.
> What are the pros and cons of each? Is 1200 DPI overkill?
I have been experimenting. My scanner, an Epson Perfection 3200 Photo,
supports up to 3200 dpi optical resolution. I have only once used it
at full resolution, just as a test of a tiny spot. I am of the opinion
that there is no reason to scan the photo past the point at which the
grain of the photos becomes obvious. My parents generally used bargain
film, whatever was cheapest, so it is not at all difficult for me to
overscan the photos, or even the negatives. Usually, 600 dpi is
sufficient, though I am increasing the resolution for the newer
photos, because the quality of the film they bought improved every few
years.
> I have mostly black & white photos to scan, but some are in
> color. Should I use the higher setting for just the color photos, both or
> neither? Any advice would be much appreciated.
Of course, b&w photos need less space for the same resolution, because
they can be scanned as grayscale, instead of color (make sure you
select grayscale instead of color when you scan them). But, I scan at
the resolution at which I begin to notice grain in the scan. I
experiment to find this resolution with each batch of photos.
> Also, I'm just planning on saving the scans in the jpeg format. Any reason
> not to? Should I be using a different file format?
For archiving in which I want to maintain the full details, I must use
a lossless file format. The difference between my scans of my 110
photos saved as TIFF and those converted to JPEG is obvious when
viewed side-by-side. Even at high-quality JPEG, the photos are
fuzzier, blurrier, than the TIFFs. Of course, they are also much
smaller.
You don't necessarily have to save your files as TIFF, but I am
somewhat familiar with its specifications, and I feel most comfortable
in using it for this purpose. Other times, I use PNG, or Adobe
Elements' native PDF. I don't remember right now if PDF is lossless,
though I think it is not.
Of course, just running my scans through all this processing loses
some image quality. Adobe Elements does not even support the color
depth at which I am scanning, and neither do some file formats. I
don't remember the bit depth that PNG suppports, but GIF is only an
8-bit format; I don't recommend using GIF for any sort of archiving,
for several reasons.
It is true that high-quality scans take up a lot of space, but I
believe this is a time to be generous, and not stingy. These scans are
meant to last for many years, and so we should take the long-term
outlook. I always try to get the highest quality product of anything
that I intend to have for a long time. Also, the cost of storage space
is dropping rapidly, and the expectations of quality are rising. One
of these days, someone is going to develop a video display with the
quality we now use for professional offset printing (probably next
century ;P).
There has been a lot of discussion about the lifespan of CDs.
Professional archivers are experimenting with many approaches to make
documents last and remain accessible for many years. No one actually
knows how long any CD can reasonably last, but proper storage
certainly helps extend their life. But, home-burned CDs are based on
dyes, and the lifespan of the information on the home-burned CD cannot
be more secure than the dye (OK, some scientist may develop a way to
recover the information from a CD based on nano-trace samples
remaining on the plastic, or some such). The approach I am using now
is to save on both archival hard drives and CD/DVD media. The magnetic
media is likely to be readable (with appropriate technology) for
centuries, probably longer than the DVDs. Of course, the hard drives
cost more than the DVDs.
In the end, you should anticipate that your data may have to be
converted to new formats, but physically and logically, from
time-to-time.
| |
|
|
| Voivod 2004-05-22, 4:28 am |
| On Sat, 22 May 2004 00:55:42 GMT, "Erik Muna" <petfish@shaw.ca>
scribbled:
> So how come my audio CD's from the early 90's are still 100% playable
>even after a LOT of use over the years? In my opinion, *if* CD's don't work
Because commercially produced CD media is pressed, not burned.
| |
| Xalinai 2004-05-22, 7:28 am |
| On Fri, 21 May 2004 22:20:50 GMT, "Nikko" <nothanks@yourmomma.com>
wrote:
>I'm about to start the process of scanning hundreds of old family photos. I
>don't really know a ton about how this stuff works and would love to have a
>few questions answered before I get too far into the project.
>
>My scanner supports up to 1200 DPI. The next step down is 600 DPI. I don't
>know which to use. My instinct is go with the higher DPI because we're
>going to want to have these pictures forever and the scans may end up being
>the only copies we have if something happens to the originals. On the other
>hand, the difference in size is substantial: over 26 MB for 1200 DPI and
>only 6.5 for 600 DPI. What are the pros and cons of each? Is 1200 DPI
>overkill? I have mostly black & white photos to scan, but some are in
>color. Should I use the higher setting for just the color photos, both or
>neither? Any advice would be much appreciated.
Modern paper prints usually don't have enough resolution for a scan
with more than 200-300 ppi. If you have matte paper, don't try
anything beyond 250ppi, you will only scan the matte structure detail.
Historic (1960 or earlier) color prints and handmade prints will
provide more detail (sometimes 400ppi) and very old and small B/W
prints sometimes give still more detail.
>Also, I'm just planning on saving the scans in the jpeg format. Any reason
>not to? Should I be using a different file format?
Both: Yes.
JPG is lossy and as such not a archiving format. Use a lossless
format such as TIFF or PNG to archive average size images (<12 million
pixels). What you throw away when saving as JPG can never be
recovered.
With regard to media longevity, always keep multiple copies of your
images in different locations. Give copies of the media you create to
other family members - they will be happy to get the images and you
will silently know you have another backup location.
Keep in mind that digital media becomes unreadable less because of
media age but from technical progress. Migrate data regularly to new
media (CD->DVD->???, about every 5 years) and avoid proprietary data
formats (Images as PSD) because the programs may become unavailable in
the future.
Michael
| |
| Xalinai 2004-05-22, 7:28 am |
| On Sat, 22 May 2004 00:55:42 GMT, "Erik Muna" <petfish@shaw.ca> wrote:
> So how come my audio CD's from the early 90's are still 100% playable
>even after a LOT of use over the years? In my opinion, *if* CD's don't work
>for two reasons: 1) cheap/crappy blanks and 2) cheap/crappy burners. My
>first burner was an HP and it was an early generation. A few months later I
>got a much nicer Pioneer but it wouldn't play the CD's I had just burned
>with my old drive but they *would* still play in the old drive.
>
> Since the nice new drive and new media I've had no problems archiving
>data on CD's. If a hard drive gets moved around, even a little in some
>cases, you could lose everything. Anyway, my advice would be to use
>multiple formats to store valuable things but CD's work best for me and
>maybe I'm in the minority but whatever...
The problem may be storage conditions too. Burned CDs like dark closed
spaces. Even in a jewel case on a shelf in a bright, sunlit room they
can get a "sunburn" that makes them unreadable.
And always keep at least one second copy in a different place.
Michael
| |
| Ron Hunter 2004-05-22, 7:28 am |
| Richard Alexander wrote:
> "Nikko" <nothanks@yourmomma.com> wrote in message news:<6hvrc.4886$be.2792@newsread2.news.pas.earthlink.net>...
>
>
>
> I am engaged in the same project for my family photos.
>
>
>
>
> That is my thinking, too. The pack-rat nature runs in my family. I
> hate to lose even a single bit of data.
>
>
>
>
> Yes, indeed! I recently scanned 68 photots that were taken with my
> boyhood camera, a Kodak 110. I saved each picture as a TIFF, no
> compression, 48-bit color, about 80 MB per photo. I could only fit 50
> of my scanned photos on a DVD. Those are the largest scans as a series
> that I have.
>
>
>
>
> I have been experimenting. My scanner, an Epson Perfection 3200 Photo,
> supports up to 3200 dpi optical resolution. I have only once used it
> at full resolution, just as a test of a tiny spot. I am of the opinion
> that there is no reason to scan the photo past the point at which the
> grain of the photos becomes obvious. My parents generally used bargain
> film, whatever was cheapest, so it is not at all difficult for me to
> overscan the photos, or even the negatives. Usually, 600 dpi is
> sufficient, though I am increasing the resolution for the newer
> photos, because the quality of the film they bought improved every few
> years.
>
>
>
>
> Of course, b&w photos need less space for the same resolution, because
> they can be scanned as grayscale, instead of color (make sure you
> select grayscale instead of color when you scan them). But, I scan at
> the resolution at which I begin to notice grain in the scan. I
> experiment to find this resolution with each batch of photos.
>
>
>
>
> For archiving in which I want to maintain the full details, I must use
> a lossless file format. The difference between my scans of my 110
> photos saved as TIFF and those converted to JPEG is obvious when
> viewed side-by-side. Even at high-quality JPEG, the photos are
> fuzzier, blurrier, than the TIFFs. Of course, they are also much
> smaller.
>
> You don't necessarily have to save your files as TIFF, but I am
> somewhat familiar with its specifications, and I feel most comfortable
> in using it for this purpose. Other times, I use PNG, or Adobe
> Elements' native PDF. I don't remember right now if PDF is lossless,
> though I think it is not.
>
> Of course, just running my scans through all this processing loses
> some image quality. Adobe Elements does not even support the color
> depth at which I am scanning, and neither do some file formats. I
> don't remember the bit depth that PNG suppports, but GIF is only an
> 8-bit format; I don't recommend using GIF for any sort of archiving,
> for several reasons.
>
> It is true that high-quality scans take up a lot of space, but I
> believe this is a time to be generous, and not stingy. These scans are
> meant to last for many years, and so we should take the long-term
> outlook. I always try to get the highest quality product of anything
> that I intend to have for a long time. Also, the cost of storage space
> is dropping rapidly, and the expectations of quality are rising. One
> of these days, someone is going to develop a video display with the
> quality we now use for professional offset printing (probably next
> century ;P).
>
> There has been a lot of discussion about the lifespan of CDs.
> Professional archivers are experimenting with many approaches to make
> documents last and remain accessible for many years. No one actually
> knows how long any CD can reasonably last, but proper storage
> certainly helps extend their life. But, home-burned CDs are based on
> dyes, and the lifespan of the information on the home-burned CD cannot
> be more secure than the dye (OK, some scientist may develop a way to
> recover the information from a CD based on nano-trace samples
> remaining on the plastic, or some such). The approach I am using now
> is to save on both archival hard drives and CD/DVD media. The magnetic
> media is likely to be readable (with appropriate technology) for
> centuries, probably longer than the DVDs. Of course, the hard drives
> cost more than the DVDs.
>
> In the end, you should anticipate that your data may have to be
> converted to new formats, but physically and logically, from
> time-to-time.
You REALLY need to read the information on scanning at www.scantips.com.
You are wasting time and storage space for no benefit. And as for
using uncompressed TIFF format, WHY? You can use lossless TIFF
compression (LZW) and save tons of space.
| |
| Harry Limey 2004-05-22, 7:28 am |
| Fred Langa has just published an article on the creation and storage of CD's
& DVD's
I reproduce the article in its entirety (& take no credit for this myself)
with the various reference links, for those who may have a need for this
information.
"As more and more of us switch to CDR and DVD +/-R for long-term data
storage, the question of how long the discs last, and how we can maximize
their likely lifespan, becomes more and more important. We raised the issue
of CDR longevity in "Is Your Data Disappearing?" (
http://www.informationweek.com/story/IWK20010719S0003 ) and in more detail
in "Time To Check Your CDRs" (
http://www.informationweek.com/stor...icleID=15800263 )
Since then, the problem of "disc rot" (e.g.
http://www.cnn.com/2004/TECH/ptech/...t.ap/index.html ) and
similar problems have begun to get more play. Fortunately some
organizations--- some allied with the library sciences--- have been looking
at the issue:
Fred, I uncovered what has to be the definitive guide for Disc Care:
http://www.clir.org/pubs/reports/pub121/contents.html Care and Handling of
CDs and DVDs: A Guide for Librarians and Archivists. It reiterates your
stance on labels and more. I never realized that flexing discs to remove
them from a stubborn case could be harmful. I am still looking for a high
quality CDR to replace the Kodak Golds that are no longer made. A weak CD
reader reveals just how good these are compared to others. Keep up the great
work. Greg Coutu
Hi Fred, Thanks for your list. It has saved my bacon more than once. This
article appears to go one more step in the saga of how long a CD-r can be
used for long term storage. Cd-r has been my storage of choice once they
started to gain a reputation for usability, robustness and "long" life.
http://news.independent.co.uk/world...sp?story=513486
Over the last few years I have noticed, unscientifically, that some CD-rs
are less than co-operative when re-installing operating systems for clients.
One will part install and in order to get past a stop point I use a second
copy CD. I have to say that I do not work in laboratory conditions, far from
it, but I do take a lot of care about cleanliness with my "tools" and always
store the CDs in paper covers, not touching the surface and review the
surface of all discs periodically to check for dust, cat hair and blemishes
of any sort. But still there are occasional blips in installing programs and
systems that appear to be more frequent than random. I have recently started
to transition to DVD-r but this route clearly inhibits auto start since
there are quite a lot of programs/systems stored on any one DVD. In
reviewing articles that you have printed and this later one it would appear
that DVD is the route to go if long terms needs are to be met. With the
prices of DVD writers continuing to fall and the disk cost also reducing
this seems to be a slightly more unwieldy, but productive route to take. My
use of DVD-r is only recent and have hit a few snags but I put these,
largely, down to the 1DTenT effect than product quality. Best regards,
curlew
Thanks to all who have been sending in new information, as it's discovered.
When you think of how much we're already depending on CDs and DVDs, knowing
what to expect, and how to get the most out of them, is vital!"
| |
| Johan W. Elzenga 2004-05-22, 7:28 am |
| Richard Alexander <pooua@aol.com> wrote:
>
> Yes, indeed! I recently scanned 68 photots that were taken with my
> boyhood camera, a Kodak 110. I saved each picture as a TIFF, no
> compression, 48-bit color, about 80 MB per photo. I could only fit 50
> of my scanned photos on a DVD. Those are the largest scans as a series
> that I have.
So why on earth did you do that? There is absolutely no reason to keep
images in 48 bit color. After you have done your color and density
corrections, convert them to 24 bits. And there is also no reason not to
use LZW compression if you store your photos in TIFF format. You could
have saved 4x as many photos per DVD.
--
Johan W. Elzenga johan<<at>>johanfoto.nl
Editor / Photographer http://www.johanfoto.nl/
| |
| Marvin Margoshes 2004-05-22, 7:28 pm |
|
"Nikko" <nothanks@yourmomma.com> wrote in message
news:6hvrc.4886$be.2792@newsread2.news.pas.earthlink.net...
> I'm about to start the process of scanning hundreds of old family photos.
I
> don't really know a ton about how this stuff works and would love to have
a
> few questions answered before I get too far into the project.
>
> My scanner supports up to 1200 DPI. The next step down is 600 DPI. I
don't
> know which to use. My instinct is go with the higher DPI because we're
> going to want to have these pictures forever and the scans may end up
being
> the only copies we have if something happens to the originals. On the
other
> hand, the difference in size is substantial: over 26 MB for 1200 DPI and
> only 6.5 for 600 DPI. What are the pros and cons of each? Is 1200 DPI
> overkill? I have mostly black & white photos to scan, but some are in
> color. Should I use the higher setting for just the color photos, both or
> neither? Any advice would be much appreciated.
If you are scanning prints, especially older ones, in most cases 200 dpi
gets all the detail. Compare one with the same scan at 300 dpi. You
probbaly won't see any difference.
>
> Also, I'm just planning on saving the scans in the jpeg format. Any
reason
> not to? Should I be using a different file format?
Save the image just as it comes from the scanner, with the minumum
compression. If you do image editing after that, save as a new image. Keep
the original scan as if it were the negative from a film camera. You will
later have the option to re-edit it.
>
> Thanks again for any help you can provide.
>
>
| |
| Richard Alexander 2004-05-22, 7:28 pm |
| Ron Hunter <rphunter@charter.net> wrote in message news:<10au87nl9chb47b@corp.supernews.com>...
[snip]
> You REALLY need to read the information on scanning at www.scantips.com.
Thank you for the link. I will look into it.
> You are wasting time and storage space for no benefit. And as for
> using uncompressed TIFF format, WHY? You can use lossless TIFF
> compression (LZW) and save tons of space.
Why? Because I can...
It is true that I could have used lossless compression on the TIFF
images. At the least, I could have simply WinZipped them. TIFFs
compress very nicely, as much as 98% (typically in the 80% range)
using WinZip. But, I did not do that. Fortunately, if I change my
mind, the disks I used were DVD+RW.
I have a negative impression of LZW compression, after Unisys began
demanding royalty payments for them. Even though the U.S. LZW patent
expired 30 June 2003, I still generally avoid using the technique.
| |
| Frank ess 2004-05-22, 7:28 pm |
| Marvin Margoshes wrote:
> "Nikko" <nothanks@yourmomma.com> wrote in message
> news:6hvrc.4886$be.2792@newsread2.news.pas.earthlink.net...
>
> If you are scanning prints, especially older ones, in most cases 200
> dpi gets all the detail. Compare one with the same scan at 300 dpi.
> You probbaly won't see any difference.
>
My experience is that for small prints (~3" x 3" or smaller) there is
some advantage in hyping up the dpi, if only when doing your
spot-scratch cleanup: the edges you work with will have more pixels to
choose among for selecting-in and -out.
To my intuitive eye, the higher-number scan rate yields more convincing
"enlargements", if you want to turn your 3x3-inch picture into a 6x, for
instance.
Case on point: I scanned the original (drugstore print from a little
green Kodak) at 300dpi. Displayed on a 19" monitor at 1024x768 it was
easy to see there was something in the background; zooming in just
didn't add any information to what you could see, just showed fatter
pixels and compression wrinkles. Scanned at 600dpi you could actually
check it out for some stuff. Scanned at 1200dpi, the image resized and
saved-for-Web at Photo Shop JPEG 31 quality, there is much less in the
way of blocking and a much 'cleaner' appearance than the one produced at
300dpi at the same display size.
http://tinyurl.com/22dd5
My custom and practice is to scan 8x10s at 300dpi, figuring that unless
they were originally captured on something 4x5 or larger, all the useful
detail is there on the print.
I ordinarily do 5x7s at 600dpi, and depending on the quality of print,
most smaller ones at that same level. Depending on the projected use,
there may be justification for 1200dpi scans of just about any print,
but my library contains very few of those. Usually, 3x3 or smaller
prints are not of a quality that yields anything useful at the higher
dpi rates.
35mm slides and film scans I do in a HP PhotoSmart S20, which yields
3000x2000 images, plenty good for my purposes, which are to archive and
display for the information content. As an example, there is a picture
on this Web page that consists of a full-frame 35mm slide scan. Click on
the picture to "drill down" to a larger version, and once again to see
what is actually in there at the 2400dpi scan rate of the HP S20.
http://tinyurl.com/37n5t
I'm always eager to get as much as possible of the available
information, and in this case I think it's pretty much all there. If you
want more detail, it seems to me you should get closer with your camera.
Frank ess
| |
| Ron Hunter 2004-05-22, 7:28 pm |
| Richard Alexander wrote:
> Ron Hunter <rphunter@charter.net> wrote in message news:<10au87nl9chb47b@corp.supernews.com>...
>
> [snip]
>
>
>
>
> Thank you for the link. I will look into it.
>
>
>
>
> Why? Because I can...
>
> It is true that I could have used lossless compression on the TIFF
> images. At the least, I could have simply WinZipped them. TIFFs
> compress very nicely, as much as 98% (typically in the 80% range)
> using WinZip. But, I did not do that. Fortunately, if I change my
> mind, the disks I used were DVD+RW.
>
> I have a negative impression of LZW compression, after Unisys began
> demanding royalty payments for them. Even though the U.S. LZW patent
> expired 30 June 2003, I still generally avoid using the technique.
There are other compression methods, so even if you have moral
objections to using LZW, foregoing compression really eats up your
storage, but if you don't mind the time and expense, it saves on the
other end when you want to look at the pictures.
| |
| Roger Halstead 2004-05-22, 7:28 pm |
| On 22 May 2004 11:15:45 -0700, pooua@aol.com (Richard Alexander)
wrote:
>Ron Hunter <rphunter@charter.net> wrote in message news:<10au87nl9chb47b@corp.supernews.com>...
>
>[snip]
>
>
>Thank you for the link. I will look into it.
>
>
>Why? Because I can...
>
>It is true that I could have used lossless compression on the TIFF
>images. At the least, I could have simply WinZipped them. TIFFs
>compress very nicely, as much as 98% (typically in the 80% range)
>using WinZip. But, I did not do that. Fortunately, if I change my
>mind, the disks I used were DVD+RW.
Having used DVD RWs is not a plus. If you value the data put it on
regular DVD-R. The RWs are not even recomended for back-ups. Only
for temportary storage such as moving data from one machine to
another.
>
>I have a negative impression of LZW compression, after Unisys began
>demanding royalty payments for them. Even though the U.S. LZW patent
>expired 30 June 2003, I still generally avoid using the technique.
If you have the equipment and backup I'd not be concerned.
Myself I prefer not to use compression as I don't completely trust it.
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
| |
| JohnJ 2004-05-22, 11:28 pm |
| Roger Halstead wrote:
>
> Having used DVD RWs is not a plus. If you value the data put it on
> regular DVD-R. The RWs are not even recomended for back-ups. Only
> for temportary storage such as moving data from one machine to
> another.
I use DVD RW's as temporary backup until I'm ready to archive
to DVD-R media. I scan a bunch of photographs and before editing
I make a copy of these initial scans to RW's. As I am editing, I
copy the edit versions to RW's. After I'm finished, a week or two
later I then make my final archives to DVD-R media.
When I first got my DVD burner I purchased Memorex RW media
because that's what was available. I had problems on some burns
and was finally able to buy higher quality Verbatim DataLifePlus
media. I haven't had any problems since.
> Myself I prefer not to use compression as I don't completely trust it.
Curious. Is this an emotional response? Technically there is nothing
wrong with it.
| |
| Ron Hunter 2004-05-23, 12:08 pm |
| Roger Halstead wrote:
> On 22 May 2004 11:15:45 -0700, pooua@aol.com (Richard Alexander)
> wrote:
>
>
>
>
> Having used DVD RWs is not a plus. If you value the data put it on
> regular DVD-R. The RWs are not even recomended for back-ups. Only
> for temportary storage such as moving data from one machine to
> another.
>
>
>
>
> If you have the equipment and backup I'd not be concerned.
>
> Myself I prefer not to use compression as I don't completely trust it.
>
> Roger Halstead (K8RI & ARRL life member)
> (N833R, S# CD-2 Worlds oldest Debonair)
> www.rogerhalstead.com
You don't? I suppose you don't trust the sun to come up in the east
tomorrow either. While compressing many files together does increase
the possiblilty of loss, I don't recall ever having a problem with
getting back a file that I have compressed in the past 20 years or so.
Have you had a problem with one?
| |
| Roger Halstead 2004-05-23, 12:08 pm |
|
>
>
>Curious. Is this an emotional response? Technically there is nothing
>wrong with it.
>
Yup. After years in the industry with compression that kinda, sorta
worked, most of the time I just developed a distrust of any
compression. OTOH my D70 used compressed TIFs. It's that or jpgs.
<:-))
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
| |
| Roger Halstead 2004-05-23, 12:08 pm |
| On Sun, 23 May 2004 03:25:24 -0500, Ron Hunter <rphunter@charter.net>
wrote:
>Roger Halstead wrote:
>
>You don't? I suppose you don't trust the sun to come up in the east
>tomorrow either.
Not really. We haven't seen the sun in about a week and it was mid
day. Course we've had our years allotment of rain in less than 6
months too. Lower Michigan is definitely no loner considered a drought
area.
> While compressing many files together does increase
>the possiblilty of loss, I don't recall ever having a problem with
>getting back a file that I have compressed in the past 20 years or so.
>Have you had a problem with one?
Not in a long time. It's just I've been around compression for so
long I learned to distrust it in the early days and it's difficult to
get over.<:-))
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
| |
| Ron Hunter 2004-05-23, 12:08 pm |
| Roger Halstead wrote:
> On Sun, 23 May 2004 03:25:24 -0500, Ron Hunter <rphunter@charter.net>
> wrote:
>
>
>
>
> Not really. We haven't seen the sun in about a week and it was mid
> day. Course we've had our years allotment of rain in less than 6
> months too. Lower Michigan is definitely no loner considered a drought
> area.
>
>
>
>
> Not in a long time. It's just I've been around compression for so
> long I learned to distrust it in the early days and it's difficult to
> get over.<:-))
>
> Roger Halstead (K8RI & ARRL life member)
> (N833R, S# CD-2 Worlds oldest Debonair)
> www.rogerhalstead.com
>
>
>
My niece in Chicago was complaining about the rain as well. Looks like
more on the way. Meanwhile, it is rather dry in Texas for this time of
year.
It is rather difficult to avoid compression these days as most cameras
do JPEG as a default. So far, flash card capacity has been able to keep
up with increasing sensor size, so there is really little excuse for the
rather aggressive compression used by some cameras. I would rather have
control over it, but few cameras give more than minimal control of this
aspect.
My objection has nothing to do with reliability, but rather with the
lossy compression (JPEG), tossing data I might WANT. I would rather
have an option to save it all.
One can always compress the picture data later, but once JPEG tosses
data, it's gone for ever.
| |
|
| On Sun, 23 May 2004 03:25:24 -0500, Ron Hunter <rphunter@charter.net>
wrote:
>
>You don't? I suppose you don't trust the sun to come up in the east
>tomorrow either. While compressing many files together does increase
>the possiblilty of loss, I don't recall ever having a problem with
>getting back a file that I have compressed in the past 20 years or so.
>Have you had a problem with one?
I don't know about Roger, but I've certainly had many problems.
If the medium goes bad and a single bit is lost the whole compressed
file is gone as well. (I trust checksums even less than compression.)
In my experience all the so-called "repair" option does is *try* to
delete the offending file from the archive so one can at least get at
the rest. The key word here being "try". More often than not, all
subsequent files - even it perfectly OK - may end up being
inaccessible as well.
Now then, if a few bits go bad on an uncompressed file, given the
right tools (if the image editing program refuses to open such a file,
although some are more forgiving than others) one will be able to open
and recover most of the image. The same goes for sound files.
So, I for one, am with Roger on this one. I wouldn't compress anything
I want to keep.
Don.
| |
| Ron Hunter 2004-05-23, 12:08 pm |
| Don wrote:
> On Sun, 23 May 2004 03:25:24 -0500, Ron Hunter <rphunter@charter.net>
> wrote:
>
>
>
>
> I don't know about Roger, but I've certainly had many problems.
>
> If the medium goes bad and a single bit is lost the whole compressed
> file is gone as well. (I trust checksums even less than compression.)
> In my experience all the so-called "repair" option does is *try* to
> delete the offending file from the archive so one can at least get at
> the rest. The key word here being "try". More often than not, all
> subsequent files - even it perfectly OK - may end up being
> inaccessible as well.
>
> Now then, if a few bits go bad on an uncompressed file, given the
> right tools (if the image editing program refuses to open such a file,
> although some are more forgiving than others) one will be able to open
> and recover most of the image. The same goes for sound files.
>
> So, I for one, am with Roger on this one. I wouldn't compress anything
> I want to keep.
>
> Don.
Don,
That's up to you. You are paying. For me, compression just makes
sense. I don't compress multiple pictures into a single file for
archiving, but since most of my pictures are jpeg anyway, there really
isn't any option. For those I scan, I compress .tif files, one picture
per archive. At least that limits my loss potential.
| |
| Marvin Margoshes 2004-05-23, 7:14 pm |
|
"Ron Hunter" <rphunter@charter.net> wrote in message
news:10b0nvkpcnipdae@corp.supernews.com...
> Roger Halstead wrote:
news:<10au87nl9chb47b@corp.supernews.com>...[color=darkred]
www.scantips.com.[color=darkred]
>
> You don't? I suppose you don't trust the sun to come up in the east
> tomorrow either. While compressing many files together does increase
> the possiblilty of loss, I don't recall ever having a problem with
> getting back a file that I have compressed in the past 20 years or so.
> Have you had a problem with one?
I have some Zip disks that I compressed in Win95. I can't open them now
unless I can find a computer with Win95. Or unless I could install Win95 in
my WinxP computer. But I figure that I haven't missed the files for several
years, so they probably aren't important. Yes, I know - it is the story of
the fox and the grapes.
| |
| Xalinai 2004-05-23, 7:14 pm |
| On Sun, 23 May 2004 13:48:38 -0400, "Marvin Margoshes"
<physnospamchem@cloud9.net> wrote:
>I have some Zip disks that I compressed in Win95. I can't open them now
>unless I can find a computer with Win95. Or unless I could install Win95 in
>my WinxP computer. But I figure that I haven't missed the files for several
>years, so they probably aren't important. Yes, I know - it is the story of
>the fox and the grapes.
Rule number 378: If you want to save any information for more than
three months don't use a M$ proprietary format. Next software version
might be unable to read it.
Rule number 379: Rule 378 doesn't apply for data on Zip disks. The Zip
disk will not last longer than two months.
Most of that data losses we had were from unreadable ZIP disks - more
than on all floppies over 18 years of IT business. I count it as a
data loss if a consultant arrives at the customer with the freshly
copied ZIP disk useless, even if the data is still available in the
company.
We switched to burning CDs when we found that burning CD-Rs and
destroying them after use costs less than buying a ZIP disk and using
it until it becomes useless.
Michael
| |
| Ron Hunter 2004-05-23, 11:14 pm |
| Marvin Margoshes wrote:
> "Ron Hunter" <rphunter@charter.net> wrote in message
> news:10b0nvkpcnipdae@corp.supernews.com...
>
>
> news:<10au87nl9chb47b@corp.supernews.com>...
>
>
> www.scantips.com.
>
>
>
> I have some Zip disks that I compressed in Win95. I can't open them now
> unless I can find a computer with Win95. Or unless I could install Win95 in
> my WinxP computer. But I figure that I haven't missed the files for several
> years, so they probably aren't important. Yes, I know - it is the story of
> the fox and the grapes.
>
>
There is no reason why you can't read those files. I have floppies I
created before 1995 on an AtariST that I can read on my WinXP machine.
Perhaps you just need the right program....
| |
| Richard Alexander 2004-05-24, 4:14 am |
| Ron Hunter <rphunter@charter.net> wrote in message news:<10b2fkpauho5v2a@corp.supernews.com>...
[snip]
> There is no reason why you can't read those files.
*cough* [Microsoft] *cough*
> I have floppies I created before 1995 on an AtariST that I can read
> on my WinXP machine.
Does the AtariST use a proprietary compression scheme?
> Perhaps you just need the right program....
Most likely he needs Windows 95's command.com.
Between the OS changes and the Zip format, he may have to do a lot of
work to get his files back.
| |
|
| >> I have some Zip disks that I compressed in Win95. I can't open them now
>There is no reason why you can't read those files.
You can *READ* the files, you just can't *USE* them. The compression built into
Windows 95 was proprietary to Microsoft. No other program can uncompress the
files--and Microsoft no longer supports the format, so nowadays, Microsoft
programs can't uncompress the files, either.
--
Biohazard? Radiation hazard? SO last-century.
Nanohazard T-shirts now available! http://www.villaintees.com
Art, literature, shareware, polyamory, kink, and more:
http://www.xeromag.com/franklin.html
| |
| Richard Alexander 2004-05-24, 4:14 am |
| Roger Halstead <Delete-Invallid.groups@tm.net> wrote in message news:<n5lva09r5a4gs8p55s4aa059mq0fh8g1f5@4ax.com>...
[snip]
> Having used DVD RWs is not a plus. If you value the data put it on
> regular DVD-R. The RWs are not even recomended for back-ups. Only
> for temportary storage such as moving data from one machine to
> another.
Frankly, no home-burned DVD or CD is that great an idea for archival
purposes. All of them are based on dyes, and are inherently unstable.
If treated with care, they probably will last a long time. Keep them
out of bright light (especially sunlight) and away from temperature
extremes. Keep the humidity low. But, home-burned CDs and DVDs are not
meant to be long-term storage or archival media.
I believe that magnetic media, such as tape and hard drives, offer
more reliable archival storage for the home user. It is not easy to
delete data from magnetic media, though it can become expensive to
recover it.
I have hard drives whose only purpose is to provide archival storage.
I connect them briefly to my computer for synchronization, then put
them in anti-static bags and return them to a fireproof safe. This is
not the final solution I would like to use, but it is the best I can
do under my present circumstances.
I also burn to both CD and DVD media. So far, they have worked
reliably for me, but I don't take chances.
>
> If you have the equipment and backup I'd not be concerned.
>
> Myself I prefer not to use compression as I don't completely trust it.
Generally, I'm a big advocate of data compression, but I've had
compressed file corruption, too. As for archival purposes, I prefer to
have as few layers of complexity in the path of using the file as
possible.
BTW, I have Iomega 2 Gig Ditto tapes that I used to back up my hard
drive several years ago. Unfortunately, I cannot access that data,
because I cannot get the tape drive to work. I've cleaned the drive
several times, but it simply unspools the tape from the spindle. That
was when I could even install the tape drive on my computer.
Currently, the Ditto tape software locks up during install when I try
to install it on my machines. So, I'm not too pleased with tapes right
now.
| |
| Richard Alexander 2004-05-24, 4:14 am |
| Ron Hunter <rphunter@charter.net> wrote in message news:<10at6ciofvfjd41@corp.supernews.com>...
[snip]
> Go here:
> www.scantips.com
>
> It will explain why scanning at 600DPI would be a waste of time and disk
> space for prints.
I like the comment he made, "If you aren't sure what your future
intentions for the image might be, and won't be able to scan it again,
then it's probably best to err on the large side (if storage space
allows, up to reasonable amounts anyway)." Go and do thou likewise.
| |
| Ron Hunter 2004-05-24, 7:14 am |
| Richard Alexander wrote:
> Ron Hunter <rphunter@charter.net> wrote in message news:<10b2fkpauho5v2a@corp.supernews.com>...
>
> [snip]
>
>
>
>
> *cough* [Microsoft] *cough*
>
>
>
>
> Does the AtariST use a proprietary compression scheme?
No, it didn't. Zip compression was available, and many of the files are
compressed, but Winzip handles them.
>
>
>
>
> Most likely he needs Windows 95's command.com.
>
> Between the OS changes and the Zip format, he may have to do a lot of
> work to get his files back.
| |
| Ron Hunter 2004-05-24, 7:14 am |
| Richard Alexander wrote:
> Ron Hunter <rphunter@charter.net> wrote in message news:<10at6ciofvfjd41@corp.supernews.com>...
>
> [snip]
>
>
>
>
> I like the comment he made, "If you aren't sure what your future
> intentions for the image might be, and won't be able to scan it again,
> then it's probably best to err on the large side (if storage space
> allows, up to reasonable amounts anyway)." Go and do thou likewise.
Note that 'reasonable' in the statement. Scanning a print at anything
over 300dpi isn't likely to result in any improved detail. Just to be
sure, I scanned some old prints at 600dpi and there was no gain but
larger file size and slower scanning. In some cases, the lens of the
camera, or the flatness of the film was so bad that scanning at 100dpi
would have been adequate. Now if you are dealing with certain types of
large format pictures, you might find more detail that I see with old
snapshots.
| |
| Xalinai 2004-05-24, 7:14 pm |
| On 23 May 2004 23:21:09 -0700, pooua@aol.com (Richard Alexander)
wrote:
>Roger Halstead <Delete-Invallid.groups@tm.net> wrote in message news:<n5lva09r5a4gs8p55s4aa059mq0fh8g1f5@4ax.com>...
>
>[snip]
>
>
>Frankly, no home-burned DVD or CD is that great an idea for archival
>purposes. All of them are based on dyes, and are inherently unstable.
>If treated with care, they probably will last a long time. Keep them
>out of bright light (especially sunlight) and away from temperature
>extremes. Keep the humidity low. But, home-burned CDs and DVDs are not
>meant to be long-term storage or archival media.
I do not believe that real long term storage (10years+) is still
relevant for the home user with technical development as fast as it
is.
Good media should last from introduction of a technique to it's common
obsolecence. For home burned CDs there are CD-R available where the
manufacturer states 50 years or even 100 years under specified
conditions - they will last 10 years without a problem in a light
proof archive case.
After 10 years you will see a need to migrate to different media as
only some reare oldfashioned computers will then read a full size CD.
>I believe that magnetic media, such as tape and hard drives, offer
>more reliable archival storage for the home user. It is not easy to
>delete data from magnetic media, though it can become expensive to
>recover it.
Tell me what kind of tape a SOHO user can afford that is safe for more
than five years.
Multi-Disk-RAID arrays are quite rare among SOHO users and with
current disk capacities loss of a single disk drive will in most cases
mean loss of the whole data (who got a backup of the 250 GB drive?)
>
>Generally, I'm a big advocate of data compression, but I've had
>compressed file corruption, too. As for archival purposes, I prefer to
>have as few layers of complexity in the path of using the file as
>possible.
Lossless compression doesn't work too well for 24-bit photographic
images. It is even worse for 48-bit images because of the noise.
Lossy compression is bad for archiving because it is lossy.
Hardware compression in storage devices (Tapes) works especially bad
on large multimedia files (images, video, sound) and does not improve
at all if the file contents is already compressed (JPG, DivX, MP3).
So compression only adds what you said: Another level of complexity.
There is almost no benefit except for eliminating overhead from the
backup process as catalogs compress good and empty areas at file ends
on block devices can be avoided.
>BTW, I have Iomega 2 Gig Ditto tapes that I used to back up my hard
>drive several years ago. Unfortunately, I cannot access that data,
>because I cannot get the tape drive to work. I've cleaned the drive
>several times, but it simply unspools the tape from the spindle. That
>was when I could even install the tape drive on my computer.
>Currently, the Ditto tape software locks up during install when I try
>to install it on my machines. So, I'm not too pleased with tapes right
>now.
That's not the tape, that's Iomega. If Iomega devices were less cheap
but more reliable and the media less expensive it could have been a
real success. As it is it only sucks.
Michael
| |
| Johan W. Elzenga 2004-05-24, 7:14 pm |
| Xalinai <xalinai_Two@xalinai.de> wrote:
>
> Lossless compression doesn't work too well for 24-bit photographic
> images. It is even worse for 48-bit images because of the noise.
For 48 bits you are right. Compressed images can even be larger than
uncompressed images. For 24 bits images you are wrong: LZW compression
usually saves you 50% or even a bit more. I just took a random image
from my digital SLR camera:
48 bits, uncompressed: 34,5 MB
48 bits, compressed: 40,5 MB
24 bits, uncrompressed: 17,3 MB
24 bits, compressed: 7,7 MB
--
Johan W. Elzenga johan<<at>>johanfoto.nl
Editor / Photographer http://www.johanfoto.nl/
| |
| Marvin Margoshes 2004-05-24, 7:14 pm |
|
"Ron Hunter" <rphunter@charter.net> wrote in message
news:10b2fkpauho5v2a@corp.supernews.com...
> Marvin Margoshes wrote:
>
Win95 in[color=darkred]
several[color=darkred]
story of[color=darkred]
> There is no reason why you can't read those files. I have floppies I
> created before 1995 on an AtariST that I can read on my WinXP machine.
> Perhaps you just need the right program....
MS included proprietary compression software in Win95 because they had lost
a patent infringment suit that another company brought against the
compression software that had offered before. It was only in Win95. I've
not seen any other compression software that would read files compressed in
the Win95 software.
| |
|
| Voivod wrote:
> Because commercially produced CD media is pressed, not burned.
Commercially replicated CDs are molded, not pressed.
| |
|
| > You will always find somebody with a story of an uncle who smoked three
> packs a day and lived a hundred years.
> That doesn't make smoking any safer for the rest of us.
> Store your precious data in CDs if you are too broke to buy hard drives,
> your problem.
> As you said wisely: whatever
Not that your point isn't valid, but at the same time just because that
UK rag ran this story doesn't make it absolutely true, either...
| |
|
| >Commercially replicated CDs are molded, not pressed.
Commercial CDs are pressed. The process is similar to molding, but the process
is called "CD pressing."
The process starts with a "glass master," which is a high-precision glass die
that contains actual physical bumps where the CD pits should appear. Hot
polycarbonate plastic is pressed by the glass master in a device called a
"stamper." The polycarbonate disc is then metalized (a thin layer of aluminum
is applied to the surface); the aluminum layer is covered with varnish, and the
finished CD is silkscreened and shipped.
--
Biohazard? Radiation hazard? SO last-century.
Nanohazard T-shirts now available! http://www.villaintees.com
Art, literature, shareware, polyamory, kink, and more:
http://www.xeromag.com/franklin.html
| |
| Ron Hunter 2004-05-24, 7:14 pm |
| Marvin Margoshes wrote:
> "Ron Hunter" <rphunter@charter.net> wrote in message
> news:10b2fkpauho5v2a@corp.supernews.com...
>
>
> Win95 in
>
>
> several
>
>
> story of
>
>
>
> MS included proprietary compression software in Win95 because they had lost
> a patent infringment suit that another company brought against the
> compression software that had offered before. It was only in Win95. I've
> not seen any other compression software that would read files compressed in
> the Win95 software.
>
>
I never used any compression other than Winzip in Win95. Are you saying
you compressed your files via the OS? If so, then a Win95 machine
should be able to uncompress and rerecord you files.
| |
|
| On Mon, 24 May 2004 16:06:44 -0500, Ron Hunter <rphunter@charter.net> wrote:
>Marvin Margoshes wrote:
>I never used any compression other than Winzip in Win95. Are you saying
>you compressed your files via the OS? If so, then a Win95 machine
>should be able to uncompress and rerecord you files.
DOS 6.0 had a stolen copy of doublespace.
By the time win95 came out, MS paid off a shitload of money to symantec for
the stolen software and renamed it drivespace.
| |
| Roger Halstead 2004-05-24, 7:14 pm |
|
>There is no reason why you can't read those files. I have floppies I
They are FAT 16 compressed with an old algorithm.
>created before 1995 on an AtariST that I can read on my WinXP machine.
I believe that is far beyond the expected life of floppies.I have
thrown most of them away and I had a pile of them. I find quite a
few... 10 to 15% are no longer readable after 3 or 4 years. OTOH I
have both Zip and floppy disks that are old and readable.
I have a copy of Borland C++ that is all on the original floppies and
they are still good.
>Perhaps you just need the right program....
Win 95, or possibly 98 or 98 SE.
Then again, there are a number of compression/zip apps such as WinZip
that *might* be able to unzip those files.
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
| |
|
|
| Marvin Margoshes 2004-05-25, 7:14 pm |
|
"Ron Hunter" <rphunter@charter.net> wrote in message
news:10b4ov7br4hj3c2@corp.supernews.com...
> Marvin Margoshes wrote:
it.[color=darkred]
now[color=darkred]
lost[color=darkred]
I've[color=darkred]
in[color=darkred]
> I never used any compression other than Winzip in Win95. Are you saying
> you compressed your files via the OS? If so, then a Win95 machine
> should be able to uncompress and rerecord you files.
Correct. But I don't know anyone with a Win95 computer.
| |
| Marvin Margoshes 2004-05-25, 7:14 pm |
|
"Roger Halstead" <Delete-Invallid.groups@tm.net> wrote in message
news:n5o4b0lr82dcq3p27cp13qk45363nvvdp4@4ax.com...
>
now[color=darkred]
Win95 in[color=darkred]
several[color=darkred]
story of[color=darkred]
>
> They are FAT 16 compressed with an old algorithm.
>
>
> I believe that is far beyond the expected life of floppies.I have
> thrown most of them away and I had a pile of them. I find quite a
> few... 10 to 15% are no longer readable after 3 or 4 years. OTOH I
> have both Zip and floppy disks that are old and readable.
> I have a copy of Borland C++ that is all on the original floppies and
> they are still good.
>
>
> Win 95, or possibly 98 or 98 SE.
> Then again, there are a number of compression/zip apps such as WinZip
> that *might* be able to unzip those files.
>
> Roger Halstead (K8RI & ARRL life member)
> (N833R, S# CD-2 Worlds oldest Debonair)
> www.rogerhalstead.com
WinXP won't even show the files. There is a compressed "disk" on the Zip
disk. Perhaps there is a way to copy the whole Zip disk to a HD?
| |
| Xalinai 2004-05-25, 7:14 pm |
| On Mon, 24 May 2004 18:39:06 +0200, nomail@please.invalid (Johan W.
Elzenga) wrote:
>Xalinai <xalinai_Two@xalinai.de> wrote:
>
>
>For 48 bits you are right. Compressed images can even be larger than
>uncompressed images. For 24 bits images you are wrong: LZW compression
>usually saves you 50% or even a bit more. I just took a random image
>from my digital SLR camera:
>
>48 bits, uncompressed: 34,5 MB
>48 bits, compressed: 40,5 MB
This is what I expected.
>24 bits, uncrompressed: 17,3 MB
>24 bits, compressed: 7,7 MB
Here you were lucky. I seldom have reductions of more than 30% between
compressed/uncompressed TIFF or zipping uncompressed TIFF or BMP
files.
When writing data to a tape device that is advertised with a
compression ratio of 200:100 (LTO) or 260:100 (AIT) having lots of
compressed data will slow down your work a lot.
Michael
>
>--
>Johan W. Elzenga johan<<at>>johanfoto.nl
>Editor / Photographer http://www.johanfoto.nl/
| |
| Johan W. Elzenga 2004-05-25, 7:14 pm |
| Xalinai <xalinai_Two@xalinai.de> wrote:
>
> This is what I expected.
>
>
> Here you were lucky. I seldom have reductions of more than 30% between
> compressed/uncompressed TIFF or zipping uncompressed TIFF or BMP
> files.
It depends very much on the image. A landscape image with some blue sky
over it, may compress a lot better than an image with a lot of detail
from top to bottom.
--
Johan W. Elzenga johan<<at>>johanfoto.nl
Editor / Photographer http://www.johanfoto.nl/
| |
| Stephan 2004-05-25, 7:14 pm |
|
"Brian" <no.spam@no.spam.com> wrote in message
news:7519d$40b25cdc$d1cc6c12$2561@snip.allthenewsgroups.com...
>
> Not that your point isn't valid, but at the same time just because that
> UK rag ran this story doesn't make it absolutely true, either...
Look, I have no problem believing this story because lots of my CDs are
unusable two years after recording them.
If I hold them to the light I can see little holes in them. And I use a
pretty good brand, not cheapo CompUSA home brand crap.
I live in the tropics in a house cooled by the see breeze, OK, but still, my
CD are in sleeves.
Now if you know better, go ahead and use CDs for along time archival, I
don't care really but don't come along telling people CDs are safe.
Stephan
| |
| Stephan 2004-05-25, 7:14 pm |
|
"sun lei" <sunlei20042004@yahoo.com> wrote in message
news:532be55b.0405250033.37c1d939@posting.google.com...
> Download AlbumFamiy software at http://www.albumsfamily.com to help you
Do you realize you just posted this in a Photoshop newsgroup?
Hilarious!
Stephan
| |
| Stephan 2004-05-25, 7:14 pm |
|
"Ron Hunter" <rphunter@charter.net> wrote in message
news:10b3f2hkb03icf8@corp.supernews.com...
> Richard Alexander wrote:
news:<10b2fkpauho5v2a@corp.supernews.com>...[color=darkred]
>
> No, it didn't. Zip compression was available, and many of the files are
> compressed, but Winzip handles them.
>
Did you know Zip disks and WinZip are not exactly the same thing?
Stephan
| |
|
| > Look, I have no problem believing this story because lots of my CDs are
> unusable two years after recording them.
Definitely something wrong with your burner or your media, then - I have
CD-Rs that are way older than 2 years that read perfectly. I'm not
saying they last forever, but when quality media is burned properly they
definitely last more than 2 years.
> Now if you know better, go ahead and use CDs for along time archival, I
> don't care really but don't come along telling people CDs are safe.
I sadi nothing of the sort, so why don't you stop putting words in my
mouth, XXXXXXX.
| |
|
| > Commercial CDs are pressed. The process is similar to molding, but the process
> is called "CD pressing."
Close, but not quite. The process is not similar to molding, it *is*
molding - injection molding to be exact. The pits are located on the
"inside" of the plastic surface (not the aluminum as many people
believe); the plastic (which is delivered to the plant as bags of small
beads) is melted and injected into the mold that was created from the
glass master.
Brian
(works at Disc Makers)
| |
| Ron Hunter 2004-05-25, 9:06 pm |
| Marvin Margoshes wrote:
> "Ron Hunter" <rphunter@charter.net> wrote in message
> news:10b4ov7br4hj3c2@corp.supernews.com...
>
>
> it.
>
>
> now
>
>
> lost
>
>
> I've
>
>
> in
>
>
>
> Correct. But I don't know anyone with a Win95 computer.
>
>
Surely you can find someone. Hint think schools. They usually have a
collection of antique hardware....
| |
| Richard Alexander 2004-05-25, 9:06 pm |
| "Stephan" <NoMoreSpam@Thank.you> wrote in message news:<H4Msc.506$eQ5.23@twister.socal.rr.com>...
[snip]
> my CDs are
> unusable two years after recording them.
> If I hold them to the light I can see little holes in them. And I use a
> pretty good brand, not cheapo CompUSA home brand crap.
> I live in the tropics in a house cooled by the see breeze, OK, but still, my
> CD are in sleeves.
I have heard of a fungus or bacteria that eats the aluminum part of
pressed CDs. I wonder if there is a bug that eats the dyes in CD-R?
| |
| Ron Hunter 2004-05-25, 9:06 pm |
| Xalinai wrote:
> On Mon, 24 May 2004 18:39:06 +0200, nomail@please.invalid (Johan W.
> Elzenga) wrote:
>
>
>
>
>
>
> This is what I expected.
>
>
>
>
> Here you were lucky. I seldom have reductions of more than 30% between
> compressed/uncompressed TIFF or zipping uncompressed TIFF or BMP
> files.
>
> When writing data to a tape device that is advertised with a
> compression ratio of 200:100 (LTO) or 260:100 (AIT) having lots of
> compressed data will slow down your work a lot.
>
> Michael
>
>
>
>
Compression depends largely on the nature of the original data. If you
take pictures of trees and grass, you will get little help from
compression. If you take picture of a lot of sky, or walls of a single
color, or pattern, then you will get better compression.
| |
| Roger Halstead 2004-05-25, 9:06 pm |
| On Tue, 25 May 2004 18:17:11 GMT, "Stephan" <NoMoreSpam@Thank.you>
wrote:
>
>"Brian" <no.spam@no.spam.com> wrote in message
>news:7519d$40b25cdc$d1cc6c12$2561@snip.allthenewsgroups.com...
>
>Look, I have no problem believing this story because lots of my CDs are
>unusable two years after recording them.
>If I hold them to the light I can see little holes in them. And I use a
>pretty good brand, not cheapo CompUSA home brand crap.
>I live in the tropics in a house cooled by the see breeze, OK, but still, my
>CD are in sleeves.
>Now if you know better, go ahead and use CDs for along time archival, I
>don't care really but don't come along telling people CDs are safe.
In general they are and the industry says so as well.
OTOH, no media is infallible and magnetic is considered one of the
lest safe for archiving.
Tapes and hard drives are normally used for rolling back ups where the
data is refreshed on a continuing basis, not archiving.
>
You may have had bad luck, but currently quality CDs and DVDs are
considered the longest lived method for storing data.
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
>Stephan
>
| |
| Stephan 2004-05-26, 7:14 am |
|
"Richard Alexander" <pooua@aol.com> wrote in message
news:d8fbbe2d.0405251521.625557f5@posting.google.com...
> "Stephan" <NoMoreSpam@Thank.you> wrote in message
news:<H4Msc.506$eQ5.23@twister.socal.rr.com>...
>
> [snip]
>
still, my[color=darkred]
>
> I have heard of a fungus or bacteria that eats the aluminum part of
> pressed CDs. I wonder if there is a bug that eats the dyes in CD-R?
I never heard of that but it is exactly how some of the damage looks: like
something that grows, something organic.
First a hole and then it spreads, a bit like fungus in a camera lens.
Stephan
| |
| Stephan 2004-05-26, 7:14 am |
|
"Roger Halstead" <Delete-Invallid.groups@tm.net> wrote in message
news:bim7b0lc79esdbasse2aenjs6kji8amg4r@4ax.com...
> On Tue, 25 May 2004 18:17:11 GMT, "Stephan" <NoMoreSpam@Thank.you>
> wrote:
>You may have had bad luck, but currently quality CDs and DVDs are
> considered the longest lived method for storing data.
>
Personally I think a hard drive is much safer (two hard drives in fact)
Stephan
| |
| Stephan 2004-05-26, 7:14 am |
|
"Brian" <no.spam@no.spam.com> wrote in message
news:a3382$40b38ff6$d1cc6c12$11763@snip.allthenewsgroups.com...
> XXXXXXX.
I love you too
Stephan
| |
| Stuart 2004-05-26, 7:14 am |
| Brian wrote:
> Not that your point isn't valid, but at the same time just because that
> UK rag ran this story doesn't make it absolutely true, either...
It is quite a respected broadsheet paper.
Stuart
| |
| Brian 2004-05-26, 12:14 pm |
| > It is quite a respected broadsheet paper.
It may be, but it seems that there are quite a number of well-respected
voices providing very opposing views on this issue, and since enough
time has not really passed to provide any actual real-world evidence
it's all conjecture at this point.
I'm not taking sides here; like many I have a large number of CD-Rs
containing valuable data that I want to protect by whatever means
necessary. I'm merely saying that all these folks who are claiming to
have the absolute answer on this issue are not speaking from their upper
orifice, if you catch my drift.
| |
| Xalinai 2004-05-26, 12:14 pm |
| On Tue, 25 May 2004 23:47:27 GMT, Roger Halstead
<Delete-Invallid.groups@tm.net> wrote:
>On Tue, 25 May 2004 18:17:11 GMT, "Stephan" <NoMoreSpam@Thank.you>
>wrote:
>
>
>In general they are and the industry says so as well.
>
>OTOH, no media is infallible and magnetic is considered one of the
>lest safe for archiving.
>
>Tapes and hard drives are normally used for rolling back ups where the
>data is refreshed on a continuing basis, not archiving.
>You may have had bad luck, but currently quality CDs and DVDs are
>considered the longest lived method for storing data.
>
All kind of media is subject to aging.
All CD-Rs have a very thin "protection" for dye and reflective metal
that is made from thin lacquer in a spin cover process. This may be
less than perfect and lead to destruction of metal or dye depending on
other enviromental influences.
Archive grade CD-Rs use gold instead of cheaper metals and more
resistand dyes - gold isn't subject to oxidation even if the
protective coat is substandard.
DVD-Rs have metal and dye in the middle of two layers of
polycarbonate. Their protection is much better as long as the seal
around the border and the center hole is good. So with regard to
longevity DVD-R should be the better choice, once the current overall
problems with media quality are overcome.
Tape media is stressed when used. Either it is moved with high speed
or the head drum tries to grind avay the magnetic particles. When not
in use earth tries to erase data with its magnetic field or to copy it
from one track to the next. Certain kinds of mold are fond of magnetig
tapes. So media usage is checked in professional environments and
after a certain number of uses the tapes are replaced. The number
varies from around 20 write/verify cycles for DAT to more than 500
uses for DLT and LTO. Large tape archives always use more than one
drive to be able to copy tapes without swapping the contents to disk.
Harddisks have some age limits too. Running permanently and in large
numbers, the 500 000 MTBF hours of a server grade disk drive mean that
you lose a disk every second year when you have 20 drives.
Normal disk drives (standard consumer IDE) have a much lower MTBF, are
designed for limited load cycles (being switched off regularly after a
certain time, otherwise deduct 20% MTBF) still require efficient
cooling (Environment not always between 16-23 degrees centigrade?
Deduct 20% MTBF), and so on. Effectively, MTBF of a consumer grade
disk drive can go down to less than 50 000 hours (5.7 years), so even
with only two PCs and three disks each one disk may die per year.
Storing 80 GB of image data requires two mirrored disks (EUR 80 each).
Storing 80 GB of image data on DVDs requires 20 DVD-R. DVD+R media
costs EUR 39 for 25 disks, two sets for less than EUR 80.
Michael
| |
|
| In article <40b4ab07.111865484@news.t-online.de>, xalinai_Two@xalinai.de
(Xalinai) wrote:
> Harddisks have some age limits too. Running permanently and in large
> numbers, the 500 000 MTBF hours [...]
500k hour MTBF? Is that correct?
| |
| Richard Alexander 2004-05-26, 7:14 pm |
| "Stephan" <NoMoreSpam@Thank.you> wrote in message news:<QGXsc.3753$hM4.2176@twister.socal.rr.com>...
[snip]
>
> I never heard of that but it is exactly how some of the damage looks: like
> something that grows, something organic.
> First a hole and then it spreads, a bit like fungus in a camera lens.
I Googled up some news articles on the subject:
"Victor Cardenes, of Spain's leading scientific research body,
stumbled across the microscopic creature two years ago [1999], while
visiting Belize. Friends complained that in the hot and sticky Central
American climate, a CD had stopped working and had developed an odd
discoloration that left parts of it virtually transparent.
"Dr Cardenes and colleagues at the Superior Council for Scientific
Research in Madrid discovered a fungus was steadily eating through the
supposedly indestructible disc. The fungus had burrowed into the CD
from the outer edge, then devoured the thin aluminium layer and some
of the data-storing polycarbonate resin.
"Dr Cardenes said: 'It completely destroys the aluminium. It leaves
nothing behind.' Biologists at the council had never seen this fungus,
but concluded that it belonged to a common genus called geotrichum."
"Scientist finds fungus that eats through compact discs"
http://www.telegraph.co.uk/news/mai...8%2Fwfung18.xml
"To that ever-growing list of panaceas, you may wish to add a fungal
inhibitor—especially if you live in a tropical region. After receiving
several reports of CDs rotting in the hot, humid countries of Central
America, Spanish scientists have isolated a fungus belonging to the
Geotrichum family that actually consumes the plastic exterior and
aluminum substrate in compact discs. The fungus gets a foothold in the
disc's outer edge and gradually eats its way toward the center,
eventually making the CD unplayable. According to one BBC report on
the phenomenon, an infected disc brought back from Belize appeared to
be developing a case of citrus mold."
Scientists: CD Rot For Real
http://www.stereophile.com/news/11073/
"Some fungi are known to live on plastics and polymers, but this is
the first report of a CD being eaten by a fungus. The researchers
believe that the spores probably entered the CD in Belize.
"The rarity of this phenomenon suggests that Belize's high
temperatures and tropical humidity were crucial. To find out more, the
Spanish group has posted an offer on the internet to analyse
unreadable CDs from anyone wanting to test their disks for fungal
infection. They have also submitted their work to the journal Natur
Wissenschaften."
Fungus eats CD
http://www.nature.com/nsu/010628/010628-11.html
I still haven't seen an article that says the fungus eats the dyes,
but if it eats the plastic, the dye won't have a substrate.
| |
| Richard Alexander 2004-05-26, 7:14 pm |
| Roger Halstead <Delete-Invallid.groups@tm.net> wrote in message news:<bim7b0lc79esdbasse2aenjs6kji8amg4r@4ax.com>...
[snip]
> Tapes and hard drives are normally used for rolling back ups where the
> data is refreshed on a continuing basis, not archiving.
Just a point... As long as the substrate is intact, the magnetic
domains usually do not completely disappear. In fact, an alarm was
raised several years ago (about a dozen years ago), when Los Alamos
National Lab was able to image all the magnetic domains of a disk that
had been overwritten 7 times (they were able to see the data from each
writing, because the overwriting process does not perfectly overwrite
the entire track, and they could distinguish which writing went with
each set). Of course, the Lab has specialized equipment, and it would
be expensive to recover data this way, at least with current
technology. You may not be able to recover your data, but a future
generation might, if it is stored on a hard, encased magnetic disk.
If you are serious about archiving your data, here is a service that
may help you:
"HD-Rosetta Archival Preservation Technologies and Services"
"Norsam's patented HD-ROSETTA archival preservation process records
microfilm-like images (analog images) onto a metal disc.
"Disc Size Options*
4" x 6" (105x148 mm) up to 540 pages per disc
4" Square up to 4000 pages per disc
2" Square or Round up to 200,000 pages per disc
"* Disc size and density vary by process. Available in nickel,
stainless steel, silicon or other media."
http://www.norsam.com/rosetta.html
"HD-ROM (High-Density - Read Only Memory) is a high-capacity storage
technology developed at Norsam Technologies in conjunction with an IBM
research group that enables a disk to store hundreds of times as much
information as a CD-ROM. HD-ROM uses a very narrow, finely-focused
particle beam (charged gallium ions) to write data. HD-ROM technology
can be used to write data on different types of media, such as metal
or other durable materials, to create virtually indestructible
storage."
HD-ROM
http://searchstorage.techtarget.com...i513370,00.html
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