Focusing magifyer/loopgreenspun.com : LUSENET : Large format photography : One Thread
I currently have two different focusing loops that I use on my 4X5 view camera (Toyo 4X & Eschenbach 8X). I have recently gotten a Acculight light table and I'm using the same two loops to view transparencies on this light table. What I have noticed is all transparencies are very slightly soft when the loop is placed on top of the transparency. When I raise the loop up off the transparency approximately 1/16" for the Eschenbach and 1/8" for the Toyo, images are tack sharp. What's going on? Do I need to purchase a special loop for viewing transparencies on a light table? Thanks!
-- Ron Lawrence (firstname.lastname@example.org), July 25, 2000
They must have focusing helicals. They appear to be adjusted for reading the opposite side of a groundglass (which is correct for focusing - although they should both be "off" by the same distance on the transparancies if they're both adjusted correctly for your eyes). You'll have to refocus them to view transparencies (twist the ocular counter-clockwise).
-- Wayne DeWitt (email@example.com), July 26, 2000.
One thing I forgot to mention that may be an important issue. In my older age I'm now wearing Varilux progressive focus glasses. Lining up you glasses on the loop eye-piece for sharpe focus can be a real hassle.
-- Ron Lawrence (firstname.lastname@example.org), July 26, 2000.