p.1 #2Anyone Use Focus Bracketing For Copying Film?
Focus bracketing - it's not the intended use of that feature. If somebody is having difficulty with well-focused scans, I'd say either use manual focus lenses, shoot tethered to really see how accurate focus is, get a better holder to hold the film flatter, or (least best option) stop down.
For detail and resolution, I think it depends on the size of the film you are scanning. There is an interesting thread on NLP where Nate and a few others play around with pixel shift on 35mm film and basically all you're getting is more defined grain (i.e. no detail). If you're scanning 4x5 and higher, I think there's a lot of potential detail to extract, but then I would ask how grainy your film is.
p.1 #4Anyone Use Focus Bracketing For Copying Film?
I’ve not tried focus bracketing, because I’m using a manual focus lens. Checking focus of every negative is certainly the most time consuming step in my copying routine. Reviewers seem quite impressed with the 100mm Macro GM and the A7Rvi checks all the boxes. Likely focusing is sufficiently accurate that for a flat negative there shouldn’t be an issue, but with such a high resolution camera in use for macro work, interference starts kicking in at around f/5.6. This is a fast aperture compared to what I usually use and so I was wondering if focus bracketing and an f/5.6 aperture might complement each other.