Which Diopter for an R4 ?greenspun.com : LUSENET : Leica Photography : One Thread
I need help decicing which diooter I ned with an R4. Anyone got info on how to determine it before purchasing several.?
-- Robert P Sutton (email@example.com), November 16, 2000
This actually depends on your vision, not the camera. If you have 20/20 vision, or better (some people do) you do not need a diopter correction. If you wear glasses, and the optometrist gave you a copy of the prescription, look at the entry under "spherical" for your dominant eye (the one you look through the camera with). If you are right-eyed, look at the figure for "O.D." which means "right eye." It might say something like, '-1.5" or "-3.0" if you are nearsighted, or maybe +2.5 or so if farsighted. this is your diopter correction. It may also have an entry under "cylinder" such as "-1.0 at 100 degrees" and this is your astigmatism correction, which could be included in a custom ground corrective lens.
-- Bob Fleischman (RFXMAIL@juno.com), November 17, 2000.
Actually it depends on how you want to use the camera, with or without your glasses. In my case I wear glasses for the distance. I'm near-sighted. I also wear them using my camera because I think it too cumbersome to remove the glasses while looking through the viewfinder and putting them up again when looking directly at my subject. When looking through the viewfinder of your R4 you look actually at the focussing screen at a appearant distance of around 60 cm (25"). In my case with advancing age, I was not longer able to see the screen image sharp; it appeared to close for me, the same as when reading. So my camera needed a reading correction, a + diopter correcting glass. To determine which one I went to the camerashop where I buy most of my equipment. They have a device (for minolta but it also worked for my leicas) that can be attachhed to the camera. By turning a dial the diopter value changes and it is possible to determine the correct value by looking through the viewfinder. I did this and have now a + 1 correction in both my R3 and R4. Only the Leitz correction lens comes together with a little attachment device and it was around $ 100. But when you need it to change it is much cheaper th ask your opticien to provide you with the little glass only. On the other hand, for my M3 I don't need any correction. It works just fine for me.
Peter Ingen Housz
-- Peter Ingen Housz (firstname.lastname@example.org), November 23, 2000.