More Nikon diopter drama.

[Keith]

In a thread about my FM3A's viefinder I was fairly certain that a +1 diopter would be the answer to the slightly out of focus view I get in the Nikon's viewfinder. The prism in a Nikon SLR has a native factor of -1 and I figured I need zero due to a slight over correction in my left eye so a +1 diopter should bring it back to zero right? ... Wrong!

Fellow RFFer Craig was good enough to send me a +1 he had laying around and sad to say it's not the solution ... it now appears to have gone too far the other way! After paying a little more attention when looking at the Nikon diopter chart 😱 I've now realised that to bring a Nikon viewfinder back to no diopter value at all you need a neutral diopter not a +1!

The figure that Nikon put on their diopters actually reperesents the over all dioptric value you get in the viewfinder when it's combined with the native -1 of the prism ... so a neutral or zero diopter actually has a real world value of +1 and a diopter marked +1 is in reality +2!

And wouldn't you know it ... neutral or zero diopters are near impossible to get. Nikon in Australia don't have them and B&H have them listed as out of stock ... nothing on eBay either! :bang:

 

[BillBingham2]

I kind of remember that some of the larger Nikon retailers had this hand-held thing that had one of every diopter on it in a spinning wheel on the back and one of every focusing screen in a couple of trays, plain prism, mirror and an F Mount on the front. Sounds like you could use one.

Do you have any contacts with folks up north in Japan, gotta be one up that way. Another option is to look at the for sale list over at KEH. I can order one and send it along if it would help.

B2 (;->

 

[markwatts]

Hello Keith,

KEH appears to have +0 in Ex for 10 dollars

 

[Mister E]

Keith, I have a +0 I'll send you for free. I accidentally bought two and don't need them. Trading me for the standard eyepiece would be great!

 

[af_]

Hi Keith, I have the same problem, also with an FM3A, and now I'm completely confused by your numbers.

I have good vision (with contact lenses), and I can focus perfectly without any additional eyepiece (i.e. nothing screwed on the viewfinder), so not sure if the camera has -1 standard, or there are difference between the cameras.
The eyepiece which was on my camera does not seem to have any correction, so works perfectly, but is scratched.

I bought a "Nikon +-0 Eyepiece Correction Lens", and the image is not clear (I think it's -1 diopter), and this is what I found, of course too late (see Table):
http://www.mir.com.my/rb/photography/hardwares/classics/nikonfmseries/fm3a/htmls/index4.htm

I'm in Brisbane by the way - you too? in case you want to try out the Nikon +-0 Diopter, and maybe you have a clear one in exchange..

 

[Leigh Youdale]

Keith, (and "af")
Have you talked to Scott? I bought my diopter lenses from him nicely packed in Voigtlander boxes. You might be going about this the hard way. You know he'll take back/exchange stuff if it isn't what's needed.

 

[Keith]

Hi Keith, I have the same problem, also with an FM3A, and now I'm completely confused by your numbers.

I have good vision (with contact lenses), and I can focus perfectly without any additional eyepiece (i.e. nothing screwed on the viewfinder), so not sure if the camera has -1 standard, or there are difference between the cameras.
The eyepiece which was on my camera does not seem to have any correction, so works perfectly, but is scratched.

I bought a "Nikon +-0 Eyepiece Correction Lens", and the image is not clear (I think it's -1 diopter), and this is what I found, of course too late (see Table):
http://www.mir.com.my/rb/photography/hardwares/classics/nikonfmseries/fm3a/htmls/index4.htm

I'm in Brisbane by the way - you too? in case you want to try out the Nikon +-0 Diopter, and maybe you have a clear one in exchange..

Hi af,

What you really needed was an unmarked (no lettering) eyepiece not the +-0 which is actually optically a plus one (+1) in real terms which is why you're now having trouble.

Where abouts in Brisbane are you based ... the idea of swapping eyepieces to see the difference makes a lot of sense.

Cheers ... Keith

 

[af_]

Thanks Leigh, but who is Scott? Do you have a link? Thanks.

I bought mine from B&H and later found out they have another one which seems to be the one without any correction, I hope (called "Nikon Finder Eyepiece for FM, FE & FA Series Cameras (Replacement)" (not sure if it's ok to post links to the product here)
Cheers,
Andrei

 

[peterm1]

I realise this story does not really help you but I have recently been having diopter dramas having bought a Leica M8. After a few years of aging while using auto focus DSLR I am no longer able to focus as easily as I recall. I found the best and easiest answer to working out which diopter to buy is to go into a chemist (pharmacy) and try out their non prescription reading glasses till I found the one that gives the clearest image when viewing through the finder. In my case that is a plus 1. Of course that may not help if the camera manufacturer labels theirs differently as you suggest Nikon does. But I have heard of others doing this successfully with Leica at least. (Leica diopters for M cameras are available but expensive at around $100 each.) I am yet to put down the cash. If anyone wants to sell theirs I could be a contender.

 

[markwatts]

sorry keith,

I misunderstood also!

 

[af_]

Hi af,

What you really needed was an unmarked (no lettering) eyepiece not the +-0 which is actually optically a plus one (+1) in real terms which is why you're now having trouble.

Where abouts in Brisbane are you based ... the idea of swapping eyepieces to see the difference makes a lot of sense.

Cheers ... Keith

Thanks Keith, I've sent you a PM.
Andrei

 

[Keith]

sorry keith,

I misunderstood also!

No ... thanks for that link ... the +0 (actually a +1) is what is needed.

I have confused my self slightly ... and everyone else! 😀

Why couldn't the damned thing just have an adustable diopter like my D700 or P67ii ... or even my Fed 2 for that matter! 😛

 

[Pickett Wilson]

Because, Keith, back in the day, when these film cameras were new, we were all young and didn't need "correction"! 🙂 Boomers ruled the world.

Fortunately, as my eyes aged, the technology got better to compensate.

 

[Keith]

Because, Keith, back in the day, when these film cameras were new, we were all young and didn't need "correction"! 🙂 Boomers ruled the world.

Fortunately, as my eyes aged, the technology got better to compensate.

That doesn't explain the Fed 2 having one Pickett! 😀

Or is that something to do with Vodka and photography? 😛

 

[Bike Tourist]

Not to add to the confusion, but you need to know that the viewing distance that most Nikon viewfinders use is ONE METER. So, whatever prescription you need to view an object clearly at one meter is the correction you probably need.

I'm with you — they should have gone to adjustable diopters years ago.

 

[Keith]

Not to add to the confusion, but you need to know that the viewing distance that most Nikon viewfinders use is ONE METER. So, whatever prescription you need to view an object clearly at one meter is the correction you probably need.

I'm with you — they should have gone to adjustable diopters years ago.

I was reading about that one meter distance today Dick. I was checking my vision at that distance and when I place a page of text exactly one meter away it's a little close for my left eye and a fraction far away for my right ... the joys of monovision contact lenses! LOL

 

[Sparrow]

I was reading about that one meter distance today Dick. I was checking my vision at that distance and when I place a page of text exactly one meter away it's a little close for my left eye and a fraction far away for my right ... the joys of monovision contact lenses! LOL

.. try swopping the contacts 😱

 

[rbsinto]

....or, take any eyepiece that fits the camera, remove the glass and have your local Optometrist grind you a custom eyepiece to the correct prescription. I did that about thirty years ago for my FE and FE-2, and it worked very well.
Today, I just wear a pair of distance glasses (I'm near-sighted) when I shoot and since the Optometrist told me that the viewfinders in cameras are set to focus at infinity it cleared up my problems.

 

[paulfish4570]

All I know is the 0 diopter that came with my FE2 fits my viewing eye perfectly. That eye is far-sighted, and the farness has grown in the past couple of years; everything is crystalline from 5-6 feet out ...

 

[Keith]

All I know is the 0 diopter that came with my FE2 fits my viewing eye perfectly. That eye is far-sighted, and the farness has grown in the past couple of years; everything is crystalline from 5-6 feet out ...

My left (shooting) eye is the same ... everything past five or six feet is fine so it sounds like a zero diopter is going to be the solution Paul.