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Als
03-03-2008, 06:43 PM
I'm rendering one frame, and in the same frame I got two types of result?
If I render SAME FRAME with different portions of the frame, I get different result.
I have all frames rendered but 6, and those 6 just can't be bothered to be rendered the same as the rest of them. I had few which I rendered part by part to get same initial result.
Look at this picture:

(http://farm4.static.flickr.com/3162/2293930248_47df5608e4_b.jpg) http://farm4.static.flickr.com/3162/2293930248_47df5608e4_b.jpg

Parts of glass are tottaly black, but same image rendered again can look fine or not.
Also changing resolution of the image, gives tottaly different result.
I'm still on maya 8.5, but I'm will install sp1 after this for sure...
Any ideas?

Thanks


Als

doms
03-04-2008, 05:15 PM
A bit obvious but it could just be that you haven't turned up the ray trace limit in the render globals, try wacking it right up.

Cheers-

Als
03-05-2008, 12:05 AM
Well, its whacked up already, but if it wasn't, how could this explain different results?
Thanks for trying anyway, much appreciated!


Als

MAV4d
03-05-2008, 01:45 PM
cant see your link, and also what shader are you using? photons FG? whats the color of your enviorment?

Als
03-05-2008, 05:16 PM
I hope the link works now.
Using lglass shader, as tittle of the thread says.
Using FG, no GI, using hdr image to lit + the floor.


ALs

modernPrimitive
03-05-2008, 09:33 PM
Well, its whacked up already, but if it wasn't, how could this explain different results?
Thanks for trying anyway, much appreciated!


Als

Setting to production gives 10 refraction and reflection bounces which should be more than adequate. If you lowered refractions to say 3 then after 3 bounces the refraction ray would be killed off and you would get black in the refraction even if there was a white object behind it.

Each surface that is hit (including insides) is counted as one bounce. So, on 3 bounces the ray would travel from the camera into the scene, hit say the handle (1 bouce), change direction based on index of refraction, then hit say the back inside of the handle (2nd bounce), change direction again, then say hit the body of the glass behind the handle (3rd bouce) and then be killed off. Since all the surfaces were transparent no solid color information has been passed back to the any of the surfaces during this process so they just render as black. Now if you increase the refraction limit to 8 rays, it should pass through all the way till it gets to the grey floor then pass that colour information back in reverse order to the surfaces and they will get assigned a variation of that background rather than just black.

Hope that helps.

modernPrimitive
03-05-2008, 09:38 PM
Aaaah. Re-reading your post again I just thought of something. Make sure that visible in refractions is set to "on" on your HDRI file. Those black areas could be because the ray is bending and hitting "empty space" in your environment.

Als
03-07-2008, 09:39 PM
Raytracing is 10, 10, 20, so 8 is covered. I'll try testing it by reducing it to 8.
This is other errors I've got:

Warning: (Mayatomr.Custom) :
mia_material1: connection to light shape directionalLightShape1 detected,
linking first instance directionalLight1 instead

Info:
(Mayatomr.Nodes) :
place2dTexture4.vertexUvOne: unsupported type of connection,
current plug value used instead

Info: (Mayatomr.Nodes) :
place2dTexture4.vertexUvTwo: unsupported type of connection,
current plug value used instead

Info: (Mayatomr.Nodes) : place2dTexture4.vertexUvThree: unsupported type of connection, current plug value used instead

Info: (Mayatomr.Custom) : l_glass2: unconnected light array parameter found "lights", perform light linking

Info: (Mayatomr.Scene) : render camera: persp2_centerLeft

Linking the light or not it gives me same errors...


Still some frames black, sometimes black, sometimes not...
Any ideas to learn about MR is welcomed...

Thanks


Als

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