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JuddWack
12-01-2005, 06:35 PM
I have noticed that after painting an alpha channel and applying it a 3D model that my alpha isn't a perfect match with the color. I always have a little bit of difference between the two.

When I create my alpha I am pretty much just selecting the areas I want to be opaque and paint bucketing them.

Does anyone have any tips on a proper way to make an alpha channel. Things to avoid and keep in mind, etc.

Thanks.

Ian Jones
12-02-2005, 12:22 AM
where exactly do the differ? just around the edges?

JuddWack
12-02-2005, 01:39 AM
A few pixels outside of each selection. My suspician is that it's caused by antialiasing.

Anuxinamoon
12-04-2005, 12:20 AM
I never have actually tried this method, but my partner says it makes the best alpha maps. The way he does it is he paints the alpha channel first, by creating a new channel in the channels box. Paint it by hand with a 100% hard brush and see how it turns out.

I'm not sure how he ended up colouring it, I only saw him do it for some grass textures but have a go at experimenting anyway :)

I hope it helped!

FLCL
12-05-2005, 03:55 PM
http://www.russellbrown.com/tips_tech.html

this is by far the best masking tutorial i've found. Go to advanced masking at the bottom of the page.

cheers

>>edit. Sorry this is more for 2D than 3D but very useful all the same

Jack Youngblood
12-09-2005, 04:29 PM
The best way to tidy up an alpha with a shaggy edge is:


1. Blur the alpha slightly. This creates a graded grey fringe between the black and the white areas.

2. Play around with Levels Adjustments (middle slider I think). This will gradually convert the grey fringe into white or black depending on your settings. You will effectively be presented with a 'live' feedback of a shrinking/enlarging of your mask.

You can do this either with the mask in preview (cant remember the keystroke) or on the mask with the image in preview.


Luck

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12-09-2005, 04:29 PM
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