Introduction to Maya - Rendering in Arnold
This course will look at the fundamentals of rendering in Arnold. We'll go through the different light types available, cameras, shaders, Arnold's render settings and finally how to split an image into render passes (AOV's), before we then reassemble it i
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1
22-03-2012
, 02:09 PM
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mip_rayswitch IBL_lighting + IBL_reflection
I´d need a little advice on the mip_rayswitch node and how to properly connect things. there are some threads on the net covering this node but I can´t figure out how to make it work.
TASK:
scene lit with IBL + fg, camera + exposure_photographic.
I need to separate the reflection from the lighting. means when I have a good lighting situation most often the reflections of same hdri looks crappy and vice versa. Essentially I need the same HDRI but with different rotation values for IBL_lighting and IBL_reflection.
So I duplicated the IBL, created the mip_rayswitch and after plugging stuff here and there all my renders are still black.
any help or hint is much appreciated. if possible a screenshot with connections made would be awesome.
thanks in advance!
everything starts and ends in the right place at the right time.
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2
22-03-2012
, 04:11 PM
The Nurb Herd
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3
22-03-2012
, 05:21 PM
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any ideas how to connect IBL with the rayswitch?
everything starts and ends in the right place at the right time.
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4
23-03-2012
, 10:58 AM
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first of all this is my test scene:
and this is the materials for the sphere and the plane:
then, in the hypershade, I've created a new rayswitch node and a mia_lookup_sperical (into this node, in the texture value, i've opened my HDR environment image):
now.. the rayswitch node have multiple inputs:
EYE is for what you whant so see in the environment of the camera (like an imageplane.. or an IBL standard setup)
ENVIRONMENT is what you see in the reflection of the materials
FINALGATHER is what FG needs to illuminate your scene with your HDR image (in this channel, for a better FG result, you can blur your HDR, and reduce the image dimension to a 1/3 of the original)
this is the result with environment connected but eye and FG not connected
this with eye and environment:
this with eye, environment and FG:
hope this can help you.. and apologize for my really strange english ^_^
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5
26-03-2012
, 09:31 AM
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what I didn´t catch is where you plugged in the rayswitch -> into the materials shading group(environment) maybe?
I found a solution similar to yours, but I´d like to have a more global workflow in the future, because scenes often consist of like 100 different materials. right now I plug either a mirrorBall with same HDRI (rotated) into the shading groups environment to get different reflections, or the mia_envblur for faster calculation of environmental reflection casted by IBL itself.
to get around the envBall workaround it would be nice to have like 2 IBLs in the scene at the same time and rotate them as needed for global reflection and lighting. I tought that would be possible with the rayswitch, but I think I missunderstood the concept since rayswitch seems to be just a shader for objects, and not a switcher for deviding lighting/reflection.
thx!
everything starts and ends in the right place at the right time.
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6
26-03-2012
, 07:16 PM
The Nurb Herd
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plug your mia shader into the eye slot on the rayswitch and a chrome reflection result into the reflection slot.
i think you should be able to separate the passes... not 100% tho.
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7
26-03-2012
, 09:23 PM
Lead Modeler - Framestore
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Just suggestions....
Jay
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27-03-2012
, 06:10 PM
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i have to think about it.
everything starts and ends in the right place at the right time.
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9
02-04-2012
, 09:14 PM
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I tried to condensate my testings and needs into this one little test scene I´ve aded. the scene consists of a reflective object and a non reflective background plane.
there are 3 stages which show a little bit of the problems I am confronted with. my intention is to skip the reflections given by the IBL and use another hdr to reflect in the sphere.
I made 3 renderlayers with overrides to show the different connections, but just to explain here quickley:
stage1 (IBL reflecting)
- reflective sphere
- background
stage2 (IBL reflecting)
- reflective sphere (no changes)
- background (cutOut Opacity mapped in the shaders advanced tab)
stage3 (envBall reflecting)
- reflective sphere (envBall with different HDR mapped in the shading engines Environment slot)
- background (cutOut Opacity still mapped)
in stage 2 I try to get rid of the sharp reflection line from the background object.
in stage 3 the new envBall environment blends very strangely into the gradient of the background. how can I get rid of this?
and secondly the envBall doesn´t output the HDR same as IBL. I read once that it does some kind of image flipping. but no mather how I flip or rotate the envBall, I can´t get a similar results as from the IBL.
is there a global procedure how to use 2 different HDRIs for FG casting and reflection for all materials in the scene at once? or maybe just for one material working that would already be grat help.
thx