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aweyrich
10-24-2009, 04:44 AM
I have a 2D gif image logo file that is a square or plane shape - I imported it into Maya and in the scene it looks just fine - its transparent in the scene however when I go to render - it loses its transparency completely and the image turns grey/white where it is supposed to be transparent. I do not know what to do to keep this image transparent after the render.

If anyone has any thoughts.....I have attached two images - the second is is in the Maya scene (not rendered) - the first image is how it comes out rendered (all grey and white). Can I get advice on how to keep it transparent. (after rendering?) (it should look like the second image after rendering).

djx
10-24-2009, 07:48 AM
I've never use GIF for file textures - it may be ok but I would still suggest converting to a non-indexed format like TGA and make sure it has a correct alpha channel. Then, as long as your file texture is connected to both color and transparency on your shader then you should be ok.

Things to check:
Your fileTexture alpha channel looks correct - test by viewing in fcheck
In the fileTexture attributes make sure "alpha is luminance" is not checked.
The connections from your fileTexture to transparency should be file1.outTransparency --> blinn1.transparency (for example)
If you use TIF images, remember that mentalray will not work with LZW compression.

-- David

Fumetsu
10-24-2009, 08:18 AM
Heya, Are you using mental ray to render it?

You can try checking the "Alpha is luminance" option. You can find it inside the file node under the "Color Balace" tab.

I would also convert the .gif to a more standard format like .tga like djx suggested.

Also, are you sure you are using a transparency map?

vicmarines
10-26-2009, 08:21 PM
Maya tends to understand the white as opaque and black to transparency in the if necesary
invert this in the file node and test with check box alpha as luminance

aweyrich
11-13-2009, 02:31 AM
Hey guys - thank you for the great responses!! I keep trying to find the 'Alpha is Luminance' menu since all 3 of you said the same thing - and I cant find it to save my life. The image I am working in is simply a gif I imported from photoshop - so it isnt necessarily a texture that shows up in the hypershade where I think that Alpha is Luminance option is located....

someone please help me find this menu!!! And please tell me each step - dont assume I know where it is :)

djx
11-13-2009, 02:41 AM
"Alpha Is Luminance" is in the "Color Balance" tab of most textures attributes.

-- David

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