Nikon F100 diopter lens - how to identify?

Discussion in '35mm Cameras and Accessories' started by tkamiya, Mar 27, 2011.

  1. tkamiya

    tkamiya Member

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    On Nikon F100, one can have a diopter correction lens in the view finder. Does anyone know how to identify if one is installed and if so, what power? The one I have have no markings on it, yet turned all the way to minus direction, things aren't perfectly clear. I never had an issue like this with any other cameras Nikon or other brands. I do have strong near-sightedness but I do wear glasses when I shoot. Weird....
     
  2. CGW

    CGW Member

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    Any chance the built-in diopter adjustment is busted?
     
  3. tkamiya

    tkamiya Member

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    Seems to work, as I pull and turn the knob, the display does go fuzzy to almost sharp.
     
  4. ann

    ann Subscriber

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    the scew in type usually have a small marking of the edge indicating which power it may be, it screws into the eye finder.
    the built in kind turns and you make the adjustment from the toggle.
     
  5. CGW

    CGW Member

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    Probably misunderstood but is there a screw-on diopter eyepiece in place?
     
  6. tkamiya

    tkamiya Member

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    That's the very question I'm asking. The piece that screws in IS there. The problem is, I have no idea if this is a kind with diopter adjustment or just a plain glass.

    No marking what-so-ever, Ann.... "The toggle" on right side of the view finder is maxed out all the way to "-" side and it's still not enough.

    I just unscrewed what's on there and placed it on something. It appears to be a regular glass.
     
  7. ann

    ann Subscriber

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    if it has a built in one, and someone has added another, there will be a serious issue, I will go dig mine out of storage and take a look.

    I did use a screw in type for years, but have forgotten when nikon began making them as a built in.

    sounds like what you unscrewed might be just the glass. I will get back to you when i check my f100
     
  8. CGW

    CGW Member

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    Could the focus screen be misaligned?
     
  9. Ian C

    Ian C Member

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    See page 63 of the F100 manual for details about the diopter adjustment.

    http://www.cameramanuals.org/nikon_pdf/nikon_f100-2.pdf

    It has an internal diopter that can be varied from -3 to +1.

    Additional adjustment is available by installing external fixed diopters of -5 to +3 instead of the plan glass screw-in eyepiece.

    The standard configuration is a coated flat glass eyepiece at the rear. The internal diopter is varied by turning the diopter adjustment knob.

    If the user’s prescription is outside to the -3 to +1 range then, instead the user leaves the adjustment at 0 and buys a fixed diopter of -5 to +3 and install the fixed diopter in place of the plain rear lens to obtain the diopter correction marked on the screw-in fixed diopter.

    As it is described, it sounds like the camera is currently in the standard configuration.

    So long as the user’s prescription is within -3 to +1 diopters the built-in adjustment should accommodate his eyesight.

    If his or her eyesight is outside of this range, say, -4, then the user needs to purchase the -4 diopter eyepiece and install this instead of the plain eyepiece. The adjustment should be left at 0 or slightly displaced as needed to obtain the sharpest view.
     
  10. tkamiya

    tkamiya Member

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    Thank you Ian. I found -2 and -3 at B&H. This is so odd. I am very near sighted but I do wear glasses. This is the only camera body where default adjustment isn't sufficient. I have it all the way to the limit on minus range and it needs tad more. I'm thinking of buying -3 and use the built-in one for slightly more power.
     
  11. ann

    ann Subscriber

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    your eye doctor should be able to tell you what you need for your "viewing" eye. As if you don't get the right one, it won't help. I used the screw in type for years and as my glasses changed i had to change diopters. Am clueless what happened to the old ones.
     
  12. tkamiya

    tkamiya Member

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    Ann,

    As I turn this knob 'thing' counter clock wise, (toward the minus sign), it runs out of adjustment. In this case, do I need plus kind or minus kind of diopter lenses?? I can tell it's ALMOST there.... just little more is all I need.
     
  13. ann

    ann Subscriber

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    makes sense
     
  14. tkamiya

    tkamiya Member

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    Success! I just received and installed -2.0 diopter corrective lens. Now I can turn the "knob" and bring the focusing area to sharp focus. (yes, I took utmost care in not poking my eyes when adjusting the knob.... :smile: )