I just bought a Sony RX100 IV because it could shoot 4k. The file format is XAVC S 4k and the Record Setting is 30p 60M. How long could I record in that format on a 32gb card? What about a 64gb card, 128?
This is a Camera Raw forum. I think you will have to consult your manual or go to a Sony website for that information.
5 min at a time, though not back to back. The camera needs to cool down, which is why the 5 min limit was put in place. You'll see an overheating icon in the middle of the screen once the camera starts getting hot, and eventually it will shut off.