Compared to what the sensor can capture, the image in the viewfinder is always fuzzy. I suppose it gets worse when the image is dim, but not being able to tell exactly what you're doing is a huge problem all the time with this sort of work.hotrodder19 wrote:Now with all this dimness thru the viewfinder how do you assess whether the subject is in focus clearly to begin taking pictures ?
Are you saying that looking thru the cameras viewfinder the subject is clear, just that from the phone shot it looks fuzzy ?
The big issue for this discussion is that when focus stacking to get everything sharp, there's no margin for error. If you miss shooting foreground in focus for any reason at all, then the stack is ruined because OOF foreground on an otherwise sharp image usually looks awful. Background is more tolerant in some cases, but still it looks weird to have a whole bug in focus, except for (oops!) that farthest wingtip.
So I'm going to pretend that you had actually asked a slightly different question:
The answer to that is simple: start early and end late. Shooting extra frames at the beginning and end of the stack cost only a little more time for the shoot, and they buy a lot of assurance that nothing will go badly wrong.Now with all this [uncertainty] thru the viewfinder how do you [figure out where to start and stop] ?
To illustrate this idea, here is the final image from that paper I pointed you to, followed by the first and last of the 59 frames that I shot in the stack.
It's important to notice that the first and last frames are completely OOF. Their only purpose was to make sure that I had shot at least the first and last frames that I cared about.
The useful part of the stack was really only the 46 frames from IMG_5409 through IMG_5454, each of which contained different focused detail like this one example:
Again, the principle is to start early and end late. The time spent in shooting extra frames for insurance will be amply repaid in time saved by not having to reshoot the whole stack.
--Rik