Clamping applied to Viewport Renders
2365 10 0- Tim Crowson
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- jsmack
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By viewport do you mean opengl? I wasn't aware of any clamping difference between interactive and non-interactive renders for karma.
Karma clamps camera rays by default at 10. I usually unclamp primary rays, or at least raise it to 100, since 10 is well under the value mapped to the whitepoint under ACES RRT.
Karma clamps camera rays by default at 10. I usually unclamp primary rays, or at least raise it to 100, since 10 is well under the value mapped to the whitepoint under ACES RRT.
- Siavash Tehrani
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Using the viewport pixel inspector it does seem like values are clamped to 1, regardless of what Color Limit is set to for the Viewport Settings, or which rendersettings prim is being used in the Display Options. Maybe that's to aid the interactive denoiser? When viewport renders are saved to exr they appear to have the full range.
- jsmack
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Siavash Tehrani
Using the viewport pixel inspector it does seem like values are clamped to 1, regardless of what Color Limit is set to for the Viewport Settings, or which rendersettings prim is being used in the Display Options. Maybe that's to aid the interactive denoiser? When viewport renders are saved to exr they appear to have the full range.
Oh, I think the pixel inspector is clamped.
- Siavash Tehrani
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- jsmack
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- Tim Crowson
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Well something is definitely clamped somewhere. The pixel inspector doesn't seem to be able to show me values above 209 (or 0.8196). But is that because of a limitation with the pixel inspector, or because the viewer is clamping the output?
Attaching screenshots from a quick test. Rendering this to MPlay shows more range.
(Obviously since we have to do our lighting in the viewport, we need to be able to control clamping in the render settings and see that expected result in the viewport render... i.e. not have additional clamping applied)
Attaching screenshots from a quick test. Rendering this to MPlay shows more range.
(Obviously since we have to do our lighting in the viewport, we need to be able to control clamping in the render settings and see that expected result in the viewport render... i.e. not have additional clamping applied)
Edited by Tim Crowson - Aug. 17, 2022 12:44:39
- Tim Crowson
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- jsmack
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Tim Crowson
Well something is definitely clamped somewhere. The pixel inspector doesn't seem to be able to show me values above 209 (or 0.8196). But is that because of a limitation with the pixel inspector, or because the viewer is clamping the output?
Attaching screenshots from a quick test. Rendering this to MPlay shows more range.
(Obviously since we have to do our lighting in the viewport, we need to be able to control clamping in the render settings and see that expected result in the viewport render... i.e. not have additional clamping applied)
The pixel inspector is useless, it's giving the pixel value on screen (post lut), not in the render.
Why is your image rendered clamped though? Are you using a renderer other than karma?
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- Tim Crowson
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- jsmack
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Tim Crowson
This was with Karma (although I see the issue with other delegates too). We have a LUT in place here (although it's neutral in this case). That same LUT doesn't clamp anywhere apart from this viewer though. Even that MPLay render had that LUT in play.
By lut, do you mean a look defined in an OCIO config, or an actual old school lut? I haven't tried using luts directly in a viewer in years, so it could be that luts are applied post clamp.
Edited by jsmack - Aug. 17, 2022 14:37:40
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