Using final gather along with an HDR image.
I have some areas of translucence , basacaly glass.
The alpha unfortunity is pure white.
The areas of "glass" should be a 30% grey, but can't seem to get differening shades in the alpha channels at all with Mray.
Anyone know whats up?
ok, Never mind its not a Mray issue..its a GD maya "feature" where primary visabilty in the render makes the object check out of the color. BUT
makes it render into the alpha, is there a render flag that not only kills its visability in the color render but checks it out of the alpha as well ?
So far I have a dirty fix of cutting holes in my "light" dome, but this also effects the light of course, it'll have to do if I can't fix this. But its not making me that happy right now, I can also do passes I suppose, but ...anyway,logicaly
I would suspect it cuts out of the alpha,if it cuts out of the color.
Hello Jake,
Think this could sort you out, in the hypershade create/materials/Use background
and assign it to the objects for which you want to ditch the colour but keep the alpha.. the shader also outputs the Z, and shadow information if I remember right.
hth.
can do this, have to use the shere as the light map.
Run into the same issue when I set up geomtry as refections and turn off thier primary visability.. if I could set up a background shader to take the alpha out, though since the object is gone in the color channels it should be in the apha as well.... logicly... , and still use an image in the color it'd be cool. but that defeats the purpose of the background shader eh?
Anyway, I have a dirty fix, but surly you can take the visabilty out of the Alpha somewhere like you can the color channels ...
oh..wait...
um acualy I can jsut comp in an alpha from a render where the globe is turned off..
ok yea..comp fix there.
Use the alpha from another render replacing the messed up one. If anyone can figure out an easier fix , post it.
Oh, Hum having trouble understanding your thing.. but have you tried Env Sphere?
won't work the same way with a lightmap on it.
anyway, it works fine. the object doesn;t exist in the scene in the alpha or the color, EXCEPT in te areas of half clear "glass" the alpha is pure white becouse for some reason it is reading the object behind it rather than disguarding it completely as it should since it does everywhere else.
have you tired usign the transmat- or transmatphoton shaders?
nope. what do they do?
but hontstly its a problem that is acualy in both mray and maya renders when dealing with the areas behind a transparency when the render flag of the objects behind it is turned off, but the visability is still there.
But I'll try to look up what you mentioned.
passthrough alpha shaders for material or photon shaders.
Then i'll have to look into it. Thanks for the suggestion. Its just frustrating when the intire alpha cuts out except for the areas of transparency, seems like theres a render order mistake somewhere with translucent areas.