Render passes overexposed after Linear Dodge

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# 1 01-02-2015 , 11:17 PM

EduSciVis-er
Join Date: Dec 2005

Location: Toronto

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Render passes overexposed after Linear Dodge

For whatever reason, I can never mange to get the advertised render passes:
Diffuse + Indirect + Specular + Reflection + Refraction + Incandescent + Scatter
to equal the Beauty.

Yes, I've got linear workflow, 32-bit HDR export format (openEXR doesn't seem to play nice with photoshop?). It ends up completely blown out. I suspect it has something to do with the mia_material_x_passes material I am using. The diffuse pass had the object (a poly plane) with the mia_mat completely white. Why would that be? But even so, the other objects with simple blinns end up overexposed after all the linear dodging (add).

I generally give up with the whole render pass approach, it seems more trouble than it's worth.

-stwert

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# 2 02-02-2015 , 12:38 AM

The thin red line
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Stupid question Stwert but are you doing gamma correction...............dave

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# 3 02-02-2015 , 12:58 AM

EduSciVis-er
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Yeah, they're all in linear space. I checked the gamma in photoshop, but that's not the problem. Thanks though, Dave.

-stwert

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# 4 02-02-2015 , 03:09 AM

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So the comp looks fine until you add the specular pass? In my experience, the exposure options in Maya aren't applied to the passes.

- Genny
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# 5 02-02-2015 , 03:22 AM

EduSciVis-er
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No, actually the diffuse pass is way blown out. So do you think it's to do with my PSS settings? I reset the gamma to 1, but I left the other settings default. Gain 0.2, Knee 0.75 and compression 3.
Here's the diffuse pass and masterBeauty, just a really simple scene to figure things out.

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-stwert

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# 6 04-02-2015 , 04:02 PM

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I'd say that looks about right. It doesn't matter what your settings are on your mental ray exposure lens are. You'll have to adjust the exposure on the passes in the comp package.

- Genny
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# 7 10-02-2015 , 10:36 PM

EduSciVis-er
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So are you saying that the passes don't match the masterBeauty because the mB got the exposure settings from mr lens? I feel like the passes should add to the masterBeauty regardless of the exposure settings, not sure if that's what you're saying.

-stwert

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# 8 11-02-2015 , 10:58 PM

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The "MasterBeauty" is mandatory output and has all the camera level stuff and post process effects. The information extracted from it to create passes however, is on a shader level. So, the combined passes can look like a beauty pass but not the MasterBeauty, which is pretty much just a reference for whatever effects and grading will be applied to the combined passes in post. I hope I'm making sense (so tired atm aah).

- Genny
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