Diopter for Canon F1

I'm finally admitting that I need a +2 for my F1. Does anyone out there have one they don't need, or is there anything else that will fit the F1? (Yes, I have been watching all the usual places for one)

 

Also, I have no idea how I came to have it, but I have a -2 diopter for an F1 and will send it FOC to who ever needs it. (USA only)

Good luck to you,

 

but you might want to "want list" it with KEH, if no one comes through.

I've never had one, although I've seen a few pop up on Ebay over the years.

 

Unfortunately, I don't know of an alternate one. Nikon round eyepieces are ubiquitous and readily available. Unfortunately, they come in two sizes-a 19mm one for low eyepoint finders and 22mm for high eyepoint. Both are available new from Nikon-the HP version is still used on higher end current production, and the last LP camera was discontinued in 2006. I don't know the exact diameter of the F-1 eyepiece, but it's somewhere between these two sizes.

 

One possibility would be to have a machinist make up a step ring to fit Nikon diopter, or you might be able to do it yourself with a plain(glassless) F-1 ring and a ring from a junk Nikon body epoxied together. Neither would be pretty, but they would at least get you the help. One potential concern is that the eye relief of the F-1 finder is fairly low at 16mm, and that extra thickness MIGHT cause problems with seeing the entire frame.

 

It's a shame that built-in diopter adjustment didn't come along until the late 1980s. I don't know about Canons, but Nikons go -1 to +2(I'd assume Canons are similar). If you need a +2 for your F-1, you'd be well in that range since the standard eyepiece is -1 and adding a +2 to it makes it a +1 total.

 

BTW, although I'm now primarily a Nikon user, I still love my F-1s and use them some. Unfortunately, the relatively low eyepoint of them vs. something like an F3HP(25mm) or newer cameras that are in the 20-22mm range makes it difficult for me to use an F-1 with my glasses on.

Good luck to you,

 

but you might want to "want list" it with KEH, if no one comes through.

 

I put it on there yesterday.

Another option might be to talk to an optician and see if they can cut and fit a lens to the standard(glassless) eyepiece.

Ben beat me to it. Another possibility, if you don' care too much about looks, would be to get a +2 eyepiece for Nikon (not the HP, I guess), remove the glass from it (with a small spanner, I'm assuming), then take the glass out of the Canon eyepiece and insert the Nikon glass in the Canon eyepiece. I'm asuming it won't fall through. If it doesn't, then you can use super glue gel to secure it in place with the ring. If it does, you can still probably fit it inside the Canon ring using the super glue gel's gap closing properties -- or another glue, say an epoxy for example, that might work a bit better because of its highly viscous properties. Hey, where there's a will, there's a way.

Another possibility, if you don' care too much about looks, would be to get a +2 eyepiece for Nikon (not the HP, I guess), remove the glass from it (with a small spanner, I'm assuming), then take the glass out of the Canon eyepiece and insert the Nikon glass in the Canon eyepiece.

 

That is certainly a possibility.

 

The Nikon 19mm eyepieces are noticeably smaller-when I was playing around with them not too long ago I seem to recall that one would nearly drop completely inside the empty Canon ring. Of course, that could be used and if you have access to a lathe you could probably turn down the Nikon 19mm(ring and all) to fit neatly inside the Canon ring.

 

I don't have any diopters(I wear my glasses when photographing, and even my adjustable ones get dialed to -1-the standard for fixed diopter cameras) but newer Nikon eyepieces in either size have anti-fog glass in them. I don't recall exactly how it's fitted.

 

Something worth mentioning, though, is that the "ring" is fairly wide on the HP eyepieces, and the glass from one of those might be a good fit for the Canon. There again, you could also turn out the inside of the Canon ring if it's close. The HP eyepieces come in locking and non-locking, and I believe the locking ones tend to have wider rims and possibly smaller glass than the non-locking.

 

I'll try to measure all of this sometime this coming weekend.

Ben, you've just reminded me of something else. I "met" a fellow in one of these forums I participate in, who actually cuts out part of the acrylic plastic of old glasses of his for this diopter. I think I was bemoaning the fact that I couldn't find a proper diopter lens for my Bronica ETRSi and he suggested hacking up a pair of glasses for the eyepiece. Yeah, I reckon if you've got a dremel tool and cutting wheels, this would work. Only problem I see with his advice now is it'll get kinda tricky for me to find the best spot on the lens to cut the eyepiece from because I wear progressives. I suppose I could make a mask that would block off the lens except for the required opening, then hold the mask up to my glasses and move it around until I find the right spot, then mark it and cut it. Probably would have to do this while peering into the viewfinder of a camera though to make sure the acomodation is correct. Complicated.

You can buy cheap "readers" for down around $10 that are single diopter glasses available over quite a range. I've heard of people doing that.

I'm unclear what is the objective of using the diopter. Is it is to more clearly see the split image? Is it to see distant details more clearly? Or perhaps both of these would be accomplished at the same time.

I'm unclear what is the objective of using the diopter. Is it is to more clearly see the split image? Is it to see distant details more clearly? Or perhaps both of these would be accomplished at the same time.

If the eyes are not good, a diopter or eyeglasses is needed to focus accurately (without guessing). The split image is not very useful when focusing point is not near the center. The split image may be good enough for you but not for many others.

I have a NIB +3 Dioptric Adjustment Lens R, if that would be useful to you. Shipping shouldn't be expensive via Australia Post, if you're patient. If you need one right now then .... Shipping will be at cost only. If your sight couldn't adjust from +3 to +2, I have have friends who made new diopters with their optometrist' lab locally, and yours may could. The mount is still usable if you knock out the +3, carefully, as replacement round eyepieces seem to be often lost. Let me know.