Hi All. For those of you using one of the metal plate technical view cameras (Cambo Superwide, Alpa 12 series, Silvestri Bicam, etc), how easy is it to focus using the ground glass? Specifically, I'm interested in how bright the image is on the ground glass compared to what you see thru the viewfinder of a MF system like a Hassy or Mamiya or Contax (assuming the same wide open aperture, of course). Is the image on the ground glass bright enough to achieve tack sharp focussing?
Will a lens with a smaller image circle project a brighter image onto a ground glass than another lens with a larger image circle, assuming the same aperture (for example, will a Rodenstock HR series lens with a 70mm image circle appear brighter than a Schneider with a 110mm image circle, assuming the two lenses are at the same aperture)?
For reasons of brightness on the ground glass, is it worthwhile getting a lens with a maximum aperture of f/4 vs a lens with a maximum aperture of f/5.6?
For focussing, what power loupe do you use? 4X, 8X, 10X? I'd be using this system with a MFDB, if that makes any difference.
I assume you focus wide open, to get the brightest image possible, and then stop down to check depth of field. When stopped down to something like f/16 or smaller, is the image on the ground glass even bright enough to check depth of field?
Are there any other issues with focussing using a ground glass, other than image brightness? I realize the image will be upside down and reversed, but is there anything else?
I know some of your answers will necessarily be subjective, but I don't have ready access to such a system to check it out for myself, so I'm looking for informed opinions.