Alpha channel for shadows?

I've been trying to figure out a good way to make the shadow from a collar appear on the neck and chest of an avatar, to give the collar a bit more visual depth. I thought it I could simply draw the shadow on a separate layer, and then merge it with the layers I would normally use to make a mask for creating my alpha channel. When I do that, though, the shadow portion of the alpha channel ends up gray, which makes it semi-transparent in the final image. That shouldn't bother me much, because it should help the leading edge of the shadow feather gradually instead of having a hard border. The problem is, shadows are already pretty light, so they almost disappear when they become semi-transparent. Getting them to appear the proper darkness in the final product is a bit of a crap shoot.

Is there a nice, easy way to mask the shadow so it doesn't lose definition in the alpha channel, and so I still get it to feather gently against avatar skin? I'm sure there must be, but I'm too close to the problem to see it right away.

I would hand-paint that into the PS template. Or, you could do something a little trickier...

You could marquee select the collars, then you could copy paste. Then you could make that layer have 'drop shadow.' Make sure the drop shadow's settings are appropriate.

Yeah, I've been doing the "drop shadow" method for a while, and it's "OK." It does look artificial, though, because the generated shadow assumes that the avatar's skin is a flat surface and that the collar is a uniform distance from the avatar (that is, it doesn't have wrinkles or ruffles of its own). Hand drawn shadows ought to overcome that machine-made look. Even with the "drop shadow" method, however, the alpha channel I create from the shadow layer ends up wimpy looking. I can't control the amount of darkness because the shadow portion of the alpha is semi-transparent. It comes back to my original question.

Does my description make sense?

if I understand the question correctly.

Have you tried using different colors on the Alpha base? Other then default white? in all my experimenting I have found different colors on the alpha can give different effects.


Example, if you create a tattoo in a black base and use Grey as the base on the alpha it wont look like it was a paste on tattoo.


I've not tried this method on clothing, but maybe it can help.

It would probably help if you were include a few cropped snapshots of what you mean.

I'm not sure if i'm understanding you correctly, but from what i gather:
- you'd like to apply a semi-transparent shadow beyond the edge of your clothing, so that it casts a shadow on the avatar skin
- you would like to control the opacity of that shadow in order to accurately depict how shadows fall on the skin
- it sounds like you're getting grey in your shadows due to a background colour that is not your shadow colour.

Here's what I would do:
- fill the background layer with white temporarily in order to best see what's going on with your shadow layer
- Mask off your article of clothing, and invert your selection so that you have everything *not* clothing selected.
- create a new layer. apply your selection as a mask.
- brush in your shadow in your shadow colour (black or otherwise - sometimes i use a complimentary colour)
- When complete, change the background layer to match the colour of your shadow layer


//Edit: hehe... or what Theo said

Multiply is your friend...

Draw the texture for the shirt.

Make a seperate transparent layer, and airbrush the shadow of the collar on that layer in black. You can select and cut/erase away any 'overspray' that ends up on what should be the upper surface of the collar.

Now, put this layer above the main texture, set it to 'Multiply", and adjust the opacity to make the shadow lighter.

Thank you all for great suggestions. I think I can see a way now, using a combination of your ideas. Funny how a little thing like a shadow can be so annoying.

Rolig