I'm not convinced by the ETTR - I can see a small advantage - sort of.
The only thing it achieves (in my understanding inferred from the youtube post) is to maximise the exposure such that part of the field of view (interesting part) is not over exposed - while part of the field of view is allowed to burn out.
This does allow for reducing the effect of readout noise (by avoiding more exposures of lesser exposure time).
But - in my oppinion readout should be such a small effect that I'd suggest increase integeration time to the hilt (where no sub-frame is over exposed anywhere).
Image is always obtainable - regardless of background - if integeration time is high enough.
Sect 2.4 of the Handbook of Astronomical Processing (p50-p51) states: "One seemingly paradoxical result is that it is necessary to accumulate more total exposure time under a bright sky than that required to achieve the same result under a dark sky."
To properly deal with any gradient due to source of light-pollution being significantly to one side of the observer requires some thought - one could use special features of Photoshop etc - but I suspect that there is a better way.
Just some thoughts.
Mark C.
Last edit: 10 years 1 month ago by mjc. Reason: Typo correction
  