Photoshop - white halo around my GIF - drop shadow problem

[Bansaw]

I've done a transparent GIF in Photoshop CS2 and exported it "Save for web..."

However, my drop shadow effect dithers to WHITE and my background is shades of grey (not just one color).

How do I get rid of this white halo effect and encourage Photoshop to dither to TRANSPARENT and not white?

Tks,

[chicgeek]

Save for web again, but make sure you use alpha transparency.

[Bansaw]

Thanks!
I looked for this alpha transparency but could not find it.
Do you mean that I should create a layer from my drop-shadow then turn that selection into an Alpha channel?

I clicked next to DITHER and selected the Alpha1 that I'd just created but it didn't work very well.

I kind-of figured it out by converting it to a PNG file.
The drawback of this is that I lose my animation!:s

I may have to live without animation unless I can find a way of properly dithering my GIF.
Any comments?

Tks,

[chicgeek]

That's not at all what I mean.

Check the transparency option. I think that might be what you're needing.

[Bansaw]

Thanks chicgeek
However, your MATTE is white so a drop-shadow will dither to white. (I have a oval button)
My background is grey-black-white,not one solid color, so the dither shows up.
Using PNG solves this but I lose my animation.:s

[chicgeek]

Okay, I'm definitely no expert at graphic manipulation and I am not sure of a solution for you. (Now that I understand your problem.)

Is making it with a full black background an option, or do you require the transparency for some reason?

[Bansaw]

Thanks anyway for your time...
This URL shows the drop-shadow problem:
http://www.wise-women.org/tutorials/ps1/

Saving as PNG solves it, but PNGs don't animate of course.

[chicgeek]

Maybe Daveyboy or some other graphics genius will catch wind of this thread.

[DaveyBoy]

Yeah i don't think you can do that, I think it's just putting white in place of stuff that isn't a solid colour. Only PNG's can do that.

[chicgeek]

He came! He came! *faint*

[Varelse]

You can't have all these:
- animation
- smooth edges and/or shadow
- cross browser compatibility without a hack
- transparent background

You'll have to either accept jagged edges or re-design your animation for your background colors.

There's a trick for shadow effect - try using the semi-transparent pattern:
10101010
01010101
10101010
01010101
And it'll mimic a shadow quite well. Of course, there won't be smooth edges and gradual transparency.

You can't override file format's limitations...

[DaveyBoy]

I say scrap the animation and have nice edges - you know you wanna

[imaginemn]

Have you tried removing the colors from the color table (see chickgeek's screenshot) when you are on the "save for the web" screen? What I typically do is remove the white color(s) on the color table and then save it. Sometimes it may require to do it a few time and delete some other of the light colors. Play around with it to get the result you are looking for.

[Bansaw]

Thanks for all your tips.
The 101010101 tip was interesting, but I decided to use PNGs.
Its only IE6 that has the issue. Sooner or later they're going to have to move on.
I'd like to see an aminated PNG evolve sometime though.

Thanks all!

[greg]

the limitations of .gif do not allow for full a full range of opacity. It is either fully transparent or not.

When you are using drop shadow you are telling the shadowing part to be sort of a gradient like opacity where it goes from a relatively small % to a larger.

About the only thing I can think of is to go into your dropshadow options under layer style(blending options) and set the drop shadow size to 0. This will make it where it is a solid color with no opacity and you will have somewhat of a shadow effect with that. It is the only way it will go in .gif

[I-Got-IT!]

Can I suggest you not to save for web?

[colorexpertsbd]

Have you tried other options like 64 or 128, dithered or not dithered options?