Basic Question: What is 'Color Clamping' in VFB?

[stevejjd]

Hi all.

I'm just curious about something.

The help documents does say what Force Clamping is, https://docs.chaosgroup.com/display/...Buffer+%7C+VFB

But I still don't get what it is. What is it clamping and why?

Thanks

Steve ~

[stupendousman_dk]

It is not always visible to the human eye. it has to do with clamping the color values.
Normally you work in 8-bit color per channel (rgba eg.)
The framebuffer shows / works in much more, 16 or 32-bits (floating point) of color per channel.

when you clamp this, you are only saving the values in the space of 0-255 per channel.
when working in higher bpc you are seeing real values in the spectum 0-1 instead. But with a lot of decimals.

it is my understanding you clamp this in the vfb, so you will not get a highlight with an extremely high value, which can cause trouble in post production.

if you are saving the render in a 8 bpc format, it will be clamped anyway. so by forcing it you get a clamped color space even though the format could hold more data.

just realised this doesnt fully answer your question, but it is what i can contribute with

[stevejjd]

Thanks a lot for that explanation