Blender Discussions

[steffend]

Hi there,

I just installed ProRender 2.1.1 in Blender (Linux Mint) and while it works great, I noticed that if I F12 render an image, the beauty / combined pass is always clamped to 1.0. It doesn't matter if I uncheck the "Clamping" option in the render settings.

All other passes / AOVs like e.g. Direct Illumination or Direct Reflect have the full dynamic range. In my case the highlights are quite bright (> 60.0) while the beauty only shows 1.0.

This looks especially underwhelming when using a Filmic LUT which makes the white highlights bright grey:

And here's the "Direct Reflect" AOV of this rendering. Look at the non-color managed RGB values in the bottom left:

Is there an option that I have not yet spotted to avoid clamping the beauty?

[bsavery]

I think you might be using the Blender color management.  If you set that to raw would it show the unclamped values?

[steffend]

Thanks for your reply. Unfortunately the raw pixel values of the beauty are already clamped as you can see in the lower left corner of my screenshots (CM stands for "Color Managed" in the image editor while the values on the left show the raw pixel values):

[steffend]

I just gave the RPR plugin for Houdini 18 a quick try and it doesn't clamp the beauty. So, the "bug" is hidden somewhere inside the Blender plugin:

[steffend]

Same problem still existing in the 2.3 version of the addon.

[bsavery]

Hi Steffon.  If I take a simple scene, and just crank up the IBL > 100 I get RGB values > 1.0 here.  

[steffend]

Thanks for giving this a try. Sadly it still clips the same way as in my first post.
I'm using Linux Mint 19.3 and Blender 2.83 (if that matters).

The version of RPR is this which should be the latest:

I tried IBL with very high intensities, emissions in the Uber Shader, also with super high intensities. I also unchecked the "Clamping" option.

The shader itself is reacting correctly, i.e. I can use emitting shaders to light the scene, but everything the camera "sees" is clamped. Playing around with different Color Management settings also doesn't help.

[steffend]

If I use "False Color" in the Color Management I can see in the viewport that the values go over 1.0 (= red color, I used an emission with intensity of 10):

If I F12 render the same scene it look like this in the image editor (clamped to 1.0):