X-H2S and external ProRes Raw to Atomos Ninja V+ - Exposure

[Maxtoon]

I am trying to use my X-H2S HDMI out to a Atomos Ninja V+ to record ProRes Raw. Have it all connected and it works. What I don't understand is exposure and camera ISO settings. When the camera is set to HDMI RAW ATOMOS output, 4.8k 16:9, 29.97p, shutter of 1/60, the ISO selection changes to 1000 - 12800. From what I have read, I should be using a base ISO of either 640 (not available) or 12800. Set to 12800, you have to use a strong VND filter to avoid over-exposure. My questions: What should I be using for a base ISO, and once that is set, do I ignore the camera exposure meter and rely on the Atomos zebras and waveform displays for exposure setting?

Edited January 27, 2023 by Maxtoon
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