Computer Graphics with Photoshop - Digital camera quality (was re: 72dpi to 300dpi)

Author

Digital camera quality (was re: 72dpi to 300dpi)

Tacit

2004-05-30, 4:14 am

>"The best of the
>current generation of digital cameras records image files a little more
>than 11 megapixels." Kodak has a 14 MP camera out.

The difference in image quality between an 11 Mp camera and a 14 MP camera is
negligable.

And it misses the point. Manufacurers love to blather about the number of
pixels in a digital camera for the same reason scanner manufacturers love to
blather about resolution: because most people are too ignorant to know that
resolution is not the best measure of image quality, dynamic range is. (Of
course, most people don't even know what "dynamic range" means, so that's to be
expected.)

Dynamic range is the total amount of tonal range from light to dark that a
device can represent. If a digital camera has a particular dynamc range, what
that means in English is that anything brighter than the highest point of that
tonal range will be pure white, and anything darker than the lowest point will
be pure black.

Consumer and prosumer digital cameras tend to have a lower dynamic range than
film. That means that while the film can still capture detail in the highlights
and shadows, the digital image just shows white in the highlights and/or black
in the shadows. (It's the shadow end that's typically most problematic for
digital cameras.)

Consumer scanners have the same problem, which is why the pros make scans
intended for publication on drum scanners, even though drum scanners can cost
hundreds of times more than flatbed scanners.

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Chris Cox

2004-05-30, 11:14 pm

In article <20040529230703.13157.00000086@mb-m20.aol.com>, Tacit
<tacitr@aol.com> wrote:
>
> Consumer and prosumer digital cameras tend to have a lower dynamic range than
> film. That means that while the film can still capture detail in the
> highlights
> and shadows, the digital image just shows white in the highlights and/or black
> in the shadows. (It's the shadow end that's typically most problematic for
> digital cameras.)

You need to qualify that.

Current digital cameras have about the same dynamic range as slide film.
But both slide and digital cameras have less dynamic range than
negative film.

Chris

Uni

2004-05-30, 11:14 pm

Chris Cox wrote:
> In article <20040529230703.13157.00000086@mb-m20.aol.com>, Tacit
> <tacitr@aol.com> wrote:
>
>
>
> You need to qualify that.
>
> Current digital cameras have about the same dynamic range as slide film.

Whoa, Tacit receives a lesson in digital photography!

:-)

Uni

> But both slide and digital cameras have less dynamic range than
> negative film.
>
> Chris