BTW...
Confirmed on 60D - latest adtg_gui is able to lock the zoom factor between x5 and x10 (so the image no longer doubles). Procedure: simply locking the registers modified between x5 and x10. As expected, this doesn't work on 5D3.

Screenshot: 60D registers specific to x5 (the "was" values are from x10).
And here the registers for 700D (overridden x10 in x5) and of course the image no longer doubles it stays x10 in x5 so it's working on DIGIC 5 and maybe 5D3 has different case ?


The last two registers are related to each other you can break the image in the first one and fix it in the second (I can change the preview position with these registers in x10 but not in x5):
C0F118E0
C0F118E4
Is there better way (QEMU?) to understand these registers instead of overriding and guessing what it does ? because sometimes it's really hard to find the relationships between these.
I am pretty sure this register for fixing stretched LiveLivew in EOS M when enabling mv1080 and in other cameras when enabling 3x3 in 720p 50/60fps:
C0F11BCC = 0x50009 in mv1080 | 0x400045 in mv720
The proof: I changed [ADTG]800c to 0x4 in mv1080 so I have now stretched LiveView (white bar in the bottom the stretched LiveView to the top other wise the stretched LiveView to the bottom when enabling 3x3) then I copied the register value from mv720 in mv1080,, and the LiveView back to the normal.
Edit before releasing: the LiveView back to the stretched when recording H.264 (not our case now because we will record RAW and this will not affect the LiveView maybe but this means there are more registers to find) .
The Proof 2: I tried all other registers to solve stretched LiveView one by one with no success (from mv1080 registers values to mv720).
The problem: LiveView will stuck when copying the register value from mv1080 into mv720 and I don't know why

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