advice needed on viewfinder diopter lens

Discussion in '35mm Cameras and Accessories' started by macrorie, Jan 7, 2012.

  1. macrorie

    macrorie Member

    Messages:
    120
    Joined:
    Apr 6, 2005
    Location:
    Maine, USA
    Shooter:
    Multi Format
    Much of the time I shoot with a Nikon F2A and FM2n, and I have recently had trouble with the viewfinder focus. Although I am really nearsighted, I suspect this problem is because of increasing middle-aged close vision problems, and I wear bifocals to correct the problem. To improve my ability to focus with these cameras should I get -1 or +1 diopter viewfinder correction lenses? The problem is not severe, just enough to add some uncertaintly in focusing.
     
  2. Nicholas Lindan

    Nicholas Lindan Advertiser Advertiser

    Messages:
    2,385
    Joined:
    Sep 2, 2006
    Location:
    Cleveland, O
    Shooter:
    Multi Format
    I have the same problem. I use a +1 lens: this puts the focusing screen at infinity, or 0 diopters, where my far vision is well corrected. Nikon viewfinders are normally set to a 1 meter focus, or -1 diopters, with the standard viewfinder lens.

    In a hopeless effort to simplify things, Nikon confuses the issue by labeling the +1 lens as '0'.

    http://www.bhphotovideo.com/c/product/37306-REG/Nikon_2930_0_Diopter_for_FM2_FE2_FA.html

    Don't forget that with your glasses on you are no longer nearsighted but are now farsighted. I had to argue with the camera clerk on this one - she insisted I needed a negative diopter lens because I was nearsighted.
     
    Last edited by a moderator: Jan 7, 2012
  3. macrorie

    macrorie Member

    Messages:
    120
    Joined:
    Apr 6, 2005
    Location:
    Maine, USA
    Shooter:
    Multi Format
    Nicholas, thank you, that is exactly the information that I needed.
     
  4. rolleiman

    rolleiman Member

    Messages:
    281
    Joined:
    Oct 27, 2011
    Shooter:
    Medium Format
    I've also experience the problem of Nikon classifying the +1 as an 0. A word of warning about these diopter lenses....in my experience they have a nasty habit of unscrewing themselves and dropping off from the viewfinder while you're carrying your camera around...possibly as a result of vibration build up through carrying them in a car.......Witness the number of s/h Nikon FM2's on sale without the neutral screw in lens!....Be warned!
     
  5. Nicholas Lindan

    Nicholas Lindan Advertiser Advertiser

    Messages:
    2,385
    Joined:
    Sep 2, 2006
    Location:
    Cleveland, O
    Shooter:
    Multi Format
    I've lost them when having to remove them to mount a right-angle viewer. There is a large collection of small camera bits in the back lawn of the house.
     
  6. E. von Hoegh

    E. von Hoegh Member

    Messages:
    3,925
    Joined:
    Sep 14, 2011
    Location:
    Adirondacks
    Shooter:
    Multi Format
    By some miracle, the neutral lens is still present on my Nikkormat FtN.
     
  7. Neanderman

    Neanderman Member

    Messages:
    575
    Joined:
    Mar 22, 2004
    Location:
    Ohio River V
    Shooter:
    Large Format
    Their numbering is VERY confusing. Knowing that I wear +2 glasses to read and also knowing that the viewfinders are set to -1, I bought a +3, thinking that would get me to a +2. But the +3 is unusable! It is WAY too strong.

    Ed
     
  8. mablo

    mablo Member

    Messages:
    389
    Joined:
    Mar 2, 2009
    Shooter:
    Multi Format
    I found out some time ago that Voigtlander Bessa rangefinder correction diopters can be used with manual Nikon bodies. They can be found from -3 to +3.
     
  9. vpwphoto

    vpwphoto Member

    Messages:
    1,205
    Joined:
    Feb 21, 2011
    Location:
    Indiana
    Shooter:
    Multi Format
    I used to put a drop of clear nail polish on the threads before I screwed the one on I wanted. It stayed put without being permanent.
     
  10. macrorie

    macrorie Member

    Messages:
    120
    Joined:
    Apr 6, 2005
    Location:
    Maine, USA
    Shooter:
    Multi Format
    Yesterday I received a +1 diopter from KEH that I thought would fit only my FM2N, and to my surprise, it fits both the FM2N and the F2A. And it works perfectly: I can focus with confidence with my 35mm SLRs once again. Thanks to all who provided advice: I will be careful to avoid losing the diopter (especially since I discovered that these little lenses are not that common on the used market, and the new ones cost $27).
     
  11. E. von Hoegh

    E. von Hoegh Member

    Messages:
    3,925
    Joined:
    Sep 14, 2011
    Location:
    Adirondacks
    Shooter:
    Multi Format
    It will fit most any Nikon from the F onward. Use the fingernailpolish trick, or if you wish to go "retro" use a tiny dab of boiled linseed oil. :smile:
     
    Last edited by a moderator: Jan 13, 2012
  12. Neanderman

    Neanderman Member

    Messages:
    575
    Joined:
    Mar 22, 2004
    Location:
    Ohio River V
    Shooter:
    Large Format
    Or shellac, which is very easily dissolved with alcohol.

    Ed
     
  13. E. von Hoegh

    E. von Hoegh Member

    Messages:
    3,925
    Joined:
    Sep 14, 2011
    Location:
    Adirondacks
    Shooter:
    Multi Format
    Personally, I like safety wire. Locking tabs are good, too.:wink: