Mon Sep 21, 2020 3:19 pm
This looks like a quiet backwater of what may once have been some lively topics.
Now that I know where to look, I have been doing some testing.
The GoPro Hero 7 Black, which I am using has (perhaps had, since the Hero 8 has since been released) the highest resolution of the Hero 7’s, capable of 4k @60fps, 2.7k @120fps and 1080p@240fps.
It has two basic settings for eliminating mains frequency flicker depending if you are in a 50Hz environment (like UK) or 60Hz (like USA).
Having set this parameter, the 60Hz (USA) frame rates are basically 30, 60, 120, 240 while the 50Hz (UK) rates are 25, 50, 100, 200.
However, whatever the resolution/shutter speed combination selected for recording onto SD card, the signal is downgraded for output over HDMI and is emitted at 1080p29.97 for all 60Hz settings and 1080p25 for all 50Hz settings.
So the Atem will always display an output if matched to those settings, without the need for any additional hardware.
Also, additional hardware (Decimators or BMD's own equivalent etc) may help match cameras to each other so the Atem will show and switch them all in spite of this, but no amount of hardware will ever recover or improve the signal to a better resolution or frame rate than is output by the camera (over HDMI). In fact, it's a case of the Lowest Common Denominator.