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andhen

Transparency with alpha channels in Photoshop

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I have a picture with pixels of different degrees of transparency. To make a alpha channel, I simply LOAD SELECTION and save the selection as a channel. However, if I apply this alpha channel on the original picture, the resulting picture will not look right as transparency values are multiplied with the already transparent pixels. Is there a simple way to make the original pixels of 100% opacity? Of course, you could dublicate the original pictures (about 100 times!) but surely there must be a another way?

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Okay, i think I follow your question a little better right now.

The problem is, if you make your transparencies opaque, they won''t look right. Remember, a computer cannot display a transparent color. What you see as a transparency is still part of a color plus another color. Flattening the image is still going to be your best bet. Depending on yoru output program... for example, after effects, you can flatten the image onto a black background, and after effects can premultiply the background and pull out that black for you.

Another trick is to use alpha''s to cut something out, rather than trace around. Of course, this depends on your image. if its text, this works GREAT. (Neat trick, make an all green image, then go to your alpha channel, put your type on there... key it, and you''ll have perfectly alphaed out text). However, the technique can be used to get a nicer alpha... but its a bit of a pain. it basically involves expanding the border of your image out a bit so the alpha can cut it out rather than trace it.

Its like... you are painting. You can be sloppy around the border, because you are just planning on cutting it off. This gives you a very clean solid edge.

When you paint the edge yourself and then cut it out, it''ll be sloppy and you''ll still see the white of your canvas in parts.

So sometimes, sloppy is neat

Hope my ramblings helped...

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