Computer Graphics with Photoshop - trouble setting background to transparent

Author

trouble setting background to transparent

Kevin

2005-08-22, 7:15 pm

I've constructed a project with many layers, and now need to bring it
into PowerPoint with a transparent background. It's now coming in with
an opaque white background.

I thought I could just select the Background layer and set it to
transparent with Add Transparency Mask, but this option is grayed-out
on that layer, and I get a hint that the layer is partially locked. I
can't seem to unlock it by selecting the layer and selecting the
padlock glyph at the top of the Palette menu--it too is grayed out.

I've tried other methods, such as Extract, but can't figure out how to
make the Extract tool actually *do* anything--there doesn't seem to be
any OK button. I can't seem to make the Magic Eraser set all the pixels
in the Background layer to transparent, either, perhaps because it's
locked, or partially locked.

Any advice?

Bill Hilton

2005-08-22, 7:15 pm

>Kevin writes ...
>
>I thought I could just select the Background layer and set it to
>transparent with Add Transparency Mask, but this option is grayed-out
>on that layer ... Any advice?

Rename the bottom layer to anything other than 'Background' and you can
have your way with it ... otherwise it's locked.

Peter Wollenberg

2005-08-23, 4:14 am

"Kevin" <kevind@sonic.net> wrote:

>I've constructed a project with many layers, and now need to bring it
>into PowerPoint with a transparent background. It's now coming in with
>an opaque white background.
>
>I thought I could just select the Background layer and set it to
>transparent with Add Transparency Mask, but this option is grayed-out
>on that layer, and I get a hint that the layer is partially locked. I
>can't seem to unlock it by selecting the layer and selecting the
>padlock glyph at the top of the Palette menu--it too is grayed out.
>
>I've tried other methods, such as Extract, but can't figure out how to
>make the Extract tool actually *do* anything--there doesn't seem to be
>any OK button. I can't seem to make the Magic Eraser set all the pixels
>in the Background layer to transparent, either, perhaps because it's
>locked, or partially locked.
>
Use an alpha channel and either tif or png as the output file format.
In my hands, compressed tiffs from PS CS and CS2 do not work properly
with powerpoint, therefore, I have been using uncompressed tiff-files
since I switched to CS. Depending on the image data, it may be an
option to select the background in Powerpoint with the transparency
tool from the graphics-palette. If the background in the image
approximately matches the background color of the PPT presentation,
this may be a simple way to get a decent result.

Peter

tacit

2005-08-23, 7:14 pm

In article <n8qOe.10178$p%3.39303@typhoon.sonic.net>,
"Kevin" <kevind@sonic.net> wrote:

> I've constructed a project with many layers, and now need to bring it
> into PowerPoint with a transparent background. It's now coming in with
> an opaque white background.

You say "it's coming in." How are you bringing it in? What file format
are you using?

> I thought I could just select the Background layer and set it to
> transparent with Add Transparency Mask, but this option is grayed-out
> on that layer, and I get a hint that the layer is partially locked.

Correct. A background layer is not a layer. You can never edit the
transparency or create a mask on a background layer.

If you double-click the background layer, it will become a regular
layer. However, "Add Transparency Mask" will not solve your problem.

> I
> can't seem to unlock it by selecting the layer and selecting the
> padlock glyph at the top of the Palette menu--it too is grayed out.

Correct. You can not unlock the transparency of a "background" layer
because a background layer has no transparency--it is always opaque.

> I've tried other methods, such as Extract, but can't figure out how to
> make the Extract tool actually *do* anything--there doesn't seem to be
> any OK button. I can't seem to make the Magic Eraser set all the pixels
> in the Background layer to transparent, either, perhaps because it's
> locked, or partially locked.
>
> Any advice?

Yes. You need to save a PNG or TIFF with an alpha channel that indicates
transparency.

--
Art, photography, shareware, polyamory, literature, kink:
all at http://www.xeromag.com/franklin.html