D Log M (with Auto ISO) Superior to D Log

[MarvoAir3S]

If I may add my 1st hand testing and experience to the discussion. (I am shooting with the Air 3s and RC 2.)
I have 3 priorities to balance: 1) Maximum dynamic range, 2) Ease of exposure setting, shooting orbits into the sun, 3) Locking the exposure.
My own testing shows that when BOTH shutter speed and ISO are set to AUTO, more highlight detail is captured (while maintaining shadow detail - e.g. reflection of the sun in water). I set my desired exposure via EV adjustment (right wheel), then lock it via the assigned C2 button.
HOWEVER, the problem I need help with is that the exposure lock seems to be "lost" at a random time during the flight. I have seen other people posting about this same problem. People just reply that manual exposure should be used, which I understand. But then that extra dynamic range is lost, besides exposure choosing being more fiddly.
Anyone got any clues as to why the exposure lock function is not actually reliably locking the exposure?

 

[Filmarik]

If I may add my 1st hand testing and experience to the discussion. (I am shooting with the Air 3s and RC 2.)
I have 3 priorities to balance: 1) Maximum dynamic range, 2) Ease of exposure setting, shooting orbits into the sun, 3) Locking the exposure.
My own testing shows that when BOTH shutter speed and ISO are set to AUTO, more highlight detail is captured (while maintaining shadow detail - e.g. reflection of the sun in water). I set my desired exposure via EV adjustment (right wheel), then lock it via the assigned C2 button.
HOWEVER, the problem I need help with is that the exposure lock seems to be "lost" at a random time during the flight. I have seen other people posting about this same problem. People just reply that manual exposure should be used, which I understand. But then that extra dynamic range is lost, besides exposure choosing being more fiddly.
Anyone got any clues as to why the exposure lock function is not actually reliably locking the exposure?

TBH I never really understood this concept of Auto ISO and exposure lock working in conjuction. To me this does not make sense. You either want the ISO (or/and shutter speed) to float based on scene changing light or you want to lock them to a set value. Maybe someone wiser than me can explain... As for the AE lock, every time I touch the screen to focus, the Exposure lock dissengages itself.