>>3573808>>3573879I would say m43 hits it's limits at 1600, with 3200 usable in a pinch depending on the scene. That matches my expectations for FF with 6400 being reliable and 12,800 being usable in a pinch.
I tried this with the Sony A7r III, Sony A7 III, and 5D mark IV and results are basically the same. FF has the expected 2ev advantage. So whatever you can reliably get from FF at high ISO, subtract two stops for mft.
