Do a search on 'measurbator' and you will build in a second a list of people with a strong inferiority complex regarding the technical aspects of digital photography.
I don't care about that well known fact at all, just wanted to make it clear for anyone interested in HDR reading this thread that bringing the highlights of a scene to middle exposure values adds nothing to properly capturing a scene. Also that shots do not need to closely overlap in order to capture information properly; shooting at 2 or 3 stops intervals is more than enough.
I paste here what I posted in other forum:
For HDR capture (and I mean here strictly the
capture stage, i.e. what you did with the camera that day in which you set it on a tripod and shot a bracketed series over a high DR scene), the work is well done and it cannot be improved as long as 3 conditions are met:
- Your least exposed shot preserves the highlights of interest (ideally highlights should be just about to start clipping = ETTR)
- Your most exposed shot produced a sufficiently high exposure in the deep shadows of interest to get acceptable noise there with your camera
- The EV interval between your shots can be properly handled by your fusion software (with ZN this gap can be 3 or even 4 stops)
From those requirements, one could now think
the more the better and shoot 100 extra times to get a single output image, but it's a fact that the information was properly captured with less shots, so doing more is unnecesary and can even be damaging to final image quality (specially regarding sharpness and ghost artifacts).
If you don't shoot more than once to make a portrait of your dog, I don't see the point of shooting 7 or 10 times when 2 or 3 would suffice. This is not an opinion based on personal experience, this is simple maths based on how digital sensors internally work and corroborated in practice. I insist in the silly equation:
DR = C + (N-1) * M
DR: scene's dynamic range that can be captured
C: camera's dynamic range
N: number of shots
M: bracketing interval
If you have a Pentax K5 (C=11), and shoot 3 times at 3EV intervals: DR = 11 + (3 - 1) * 3 =
17 stops (that's huge!)
Regards