Hi B,
Let me explain the workflow:
If you want to match the cgi with a videoclip into the background, the tone map control works perfectly to it and the video into background won’t be afflicted by camera settings.
But if you have some elements into the scene that needs to be “matched” with the background video you need the shadow catcher mat so the element will cast shadows into fake elements. But the tone map control shader doesn’t works on the shadow catcher so you must remove it from the shadow catcher material otherwise you will get wrong and incorrect lighting and color.
Often who work on compositing needs to match the video with some fake object for masks or shadowing and it can’t be done without compatibility of tone map shader with shadow catcher shader.
Let me know if I explained this in a good way :)
And what if you use it in the sky/HDRI slot prior to assigning to the shadowcatcher? Would this be the same thing
Mmm what do you mean for “hdr/shader slot?” to use the picture or video for composting placed into the sky is the right way but the problem is not the tone map control shader placed into the sky or background object, the real issue of tone map control shader is if you place it into the shadow catcher material. It doesn’t works and so if you don’t use it you will see differences from sky/backgound (afflicted by tone map control shader) and the shadow catcher objects without tone map control shader.