I was operating and adjusting the keyer via a laptop running ATEM 5.1 software, but does anyone know if the results are the same when used with a Broadcast Panel for control? I have a lot of experience in lighting and keying live chromakey shoots, and I have to admit I was a bit disappointed at the range of control provided, with the same findings that it wasn't possible to totally eliminate the faint background colour cast. I borrowed an ATEM 2 M/E Production Switcher to test the Chromakey features with a view to using it for live previewing on a forthcoming 6-8 week greenscreen shoot for a UK kids TV series. You can PM me at 'garya' at Blackmagicdesign dot com. I would like to help if I can and maybe I cannot. If improved, I could also send the xml and settings so you could exactly duplicate what I have done. If you would allow me to try, could you PM me the full resolution frame of the chroma key image as well as a frame of the background? I would be happy to at least try on my system in the office next week and post back. There could be a compromise, but it is worth looking at. I think tweaking of the hue, Gain, and Y Suppress will make a big difference.

I still feel this could be improved to where it is not noticeable. The main issue is the miss match of the replacement image with respect to the background which should be the same. This should be easily removed by the crop adjustments as you have pointed out damej.

One is the line which may or may not be caused by first line or edge processing of the DVE or something. This is clear and it would be very noticeable with a moving background for sure. No excuse other than my eyes and not looking for the right thing. Now I have had my coffee, thanks Tom for pointing that out.

Chroma key 4k