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Direct editing of alpha channel

Mar 21, 2012, 06:31
Post: #1
Direct editing of alpha channel
Is it possible to directly edit the alpha channel? I need to edit it for a 3D model I've made, and its showing up as too shiney (The engine is looking at the alpha for reflectivity)
However, I have yet to see a way to edit the alpha channel directly
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Mar 21, 2012, 07:22 (This post was last modified: Mar 21, 2012 07:24 by ofnuts.)
Post: #2
RE: Direct editing of alpha channel
That's what "layer masks" are for.

You create a layer mask with "Layer/Mask/Add layer mask". In the Layer list, your layer no now has two thumbnails: the regular image, and the layer mask.

The layer mask can be edited with any tool that works on grayscale images (in you case, Levels/Curves, likely).

The default view mode while editing shows you the results of your action on the whole layer (RGB+Alpha) but you can also display the alpha channel directly. You can tell if you are working on the mask by the highlight on the thumbnails in the Layers list, but you can also check the bottom of the image window: next to the zoom factor, instead of "layer name" you will see "layer name mask".

When you are done, "Layer/Mask/Apply layer mask"

Now answering your questions on
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