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israelyang
12-09-2005, 08:25 PM
Hi all
I am texturing this horse with a transparancy channel with a grey scale image. I made sure the black in the map is true black but in the maya render it's not true transparent, the shadow is even more pronouced with the ghosting effect. I heard the clamp utility node can fix that but I read the help and couldn't figure it out. any help would be appreciated.
thanks

israel

Jozvex
12-09-2005, 11:23 PM
Hmm, I can't really tell which areas are supposed to be completely transparent because the texture is so crazy (in a good way! hehe).

What format are you saving the transparency textures in? Sometimes people have a problem where they save their displacement maps as jpegs and the compression alters the 'true black' into just 'really really dark grey splotches' and so it turns out wrong in Maya.

israelyang
12-09-2005, 11:55 PM
Jozvex
I saved the file as targa with an alpha channel. The whole thing should be completely transparent except for the colourful strokes. I tweaked the specularity but it didn't help.
by the way, nice wireframe tutorial.

israel

Jozvex
12-10-2005, 01:35 AM
Hehe, thanks!

Hmm, targas can be saved with LZM compression (or something like that) so maybe that's doing the same as jpeg compression to the black? Also, on the material under Raytracing, set the Shadow Attenuation to 0, that might help.

israelyang
12-10-2005, 01:49 AM
Hi thanks
It helps a little on the shadow, not so much on the object itself. But maybe it is as good as it can get?
again thanks for your help

israel

cgtriguy
12-10-2005, 03:14 AM
I just did a short little test and it worked fine for me. I made the texture in photoshop with a black background the put the color over top of that. I saved as a targa then mapped the file to both the color and transparancy of a blinn. The only thing I can think of is that you are actually getting a little color bleed into the black areas of you texture map that is not visible to your eye but is enough to change pixel color values to something other than true black (0,0,0).

Do you get the same problem if you make a checker pattern texture that is balck and white in your painting program and apply it? Or is it just with this texture.

israelyang
12-10-2005, 03:21 AM
Hi

I guess its the colour bleed as you described. Thanks.

Here is the cker board test, it worked fine.
To post an image, just scroll down as you post, click on 'Manage Attachments', and upload your picture.

cgtriguy
12-10-2005, 05:11 AM
More than happy to help.

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