Struggling to focus a manual film camera

[toestrap]

Having been  inspired by this place:

http://www.westendcameras.co.uk/films-28-c.asp

I've dug out my old Nikon FM/FM2n. The former has a plain focussing screen, the latter I can interchange split or plain focussing screens.

The FM2n needed a bit of light seal fettling but all seems good. However, my eyes aren't quite what they were e.g. I now need +2.5 reading glasses. I can focus the camera without glasses (with glasses it just blurs everything), but it is a bit of a struggle and takes much more time than I remember.

I've tried googling but haven't found anything useful.

Any ideas?

Thanks

[Kim]

I know nothing about old Nikons, but is there a focus adjustment for the viewfinder image?

[Biggsy]

A quick Google suggests that it's fixed, but various eyepiece correction diopters are available.

[andrew_s]

A quick Google suggests that it's fixed, but various eyepiece correction diopters are available.

That's correct, but "normal" should be for long distance vision - i.e. nothing necessary if you don't need glasses to focus on the moon.

[toestrap]

A quick Google suggests that it's fixed, but various eyepiece correction diopters are available.

That's correct, but "normal" should be for long distance vision - i.e. nothing necessary if you don't need glasses to focus on the moon.

Which is why I can use the viewfinder without glasses. (I think if I were to add a correction eyepiece I would then need to be wearing my glasses to focus)

I think my problem is more about general acuity. A poor anaolgy would be that once my eyes had 28 mega pixels, now they are down to 18. They can still focus the same, but the quality of the image ain't quite as good, hence focussing takes longer.

[Biggsy]

A quick Google suggests that it's fixed, but various eyepiece correction diopters are available.

That's correct, but "normal" should be for long distance vision - i.e. nothing necessary if you don't need glasses to focus on the moon.

It doesn't seem to work like that for me.  I need glasses for reading but not normal long distance vision, yet I need to adjust the variable diopter on my camera eyepiece well away from the default position.

[Biggsy]

It could be explained by my long vision not being as good as I think it is.  Could this apply to you as well, Toestrap?

In any case, I think you should try a diopter adjustment if your viewfinder doesn't look pin sharp.  Being able to use it without glasses doesn't mean it's as sharp for you as it could be.  I can't use my camera eyepiece (on any setting) with my glasses anyway.

Any lines or marks on the focusing screen should be used as the guide, with the lens defocused.

[Pickled Onion]

A quick Google suggests that it's fixed, but various eyepiece correction diopters are available.

That's correct, but "normal" should be for long distance vision - i.e. nothing necessary if you don't need glasses to focus on the moon.

The viewfinder for an SLR would put the virtual image at infinity, but they normally have a built-in -1 dioptre as standard. This puts the virtual image at about 1 m, so adjustment can be necessary for someone who only needs glasses for reading.

[Biggsy]

Aha!  That explains it nicely.

[toestrap]

I think that has nailed it. I've just tried focussing with +1 glasses and it is noticeably better. I shall purchase a +1 eyepiece ( a pretty modest investment) and see what happens. Once again YACF scores on those golden nuggets that Google fails to deliver. Thank you.

[rogerzilla]

I think I have a +1 but it's probably for an F3.  Nikon made a plethora of eyepieces for MF cameras although the range has settled down a little these days, or cameras have dioptre adjustment built in (screwmount Leicas had this in the 1930s until Leica realised they could make money selling dioptres for the M series).

[hellymedic]

Bear in mind that your pupil will be more dilated when using the viewfinder than it would be when looking around unencumbered.
A big pupil will reduce your eye's depth of focus, making accurate refractive correction more critical.

[scott]

FWIW, my FM2n came with the Type K focusing screen, which has both a rangefinder split and a microprism--it was always easy to focus.

They might still be available somewhere. eBay?

Edit: Here's one:

http://www.ebay.com/itm/Nikon-Focusing-Screen-K-type-split-image-rangefidner-for-FE-FM-FM2n-cameras-/201443490323?hash=item2ee6f7ba13:g:so0AAOSwNNxWEyPx