Originally posted by mcgregni Or is it a case of just guess a start point power setting, then chimp using the LCD or histogram ... ?
I don't see why it would have to be any more than that.
As for the need for a "
...fair bit of maths and physics...": Why? What for?
In the days of film where every exposure cost something and immediate feedback wasn't available, getting your exposure right before releasing the shutter was crucial. Nowadays, we can make use of immediate visual feedback and histograms.
I personally take an educated guess and then adjust from there.
If one lacks experience one can always start in the middle of the power range, then use the middle of the better half (depending on whether the shot was under- or overexposed), and so on. This takes one within one stop of the optimal exposure with at most three attempts.