Leica LTM 35mm viewfinder and old eyes

[jcb4718]

I have a 35mm f2.5 Color Skopar fitted to my Leica IIIc and have been looking for an external viewfinder. I wanted one that I could use while wearing my glasses. I considered a DIY version I read about on this forum. A company called Shapeways 3D prints the shell of a viewfinder. The optics is obtained from a Canon Owl point-and-shoot camera (readily available on Ebay). The device is easy to assemble and seemed quite robust when fitted to my camera. The eye relief was sufficient for my glasses. The optics comprises three elements: an eyepiece which has the brightlines on its inside, a central element having a mirror around its edge and which therefore creates an virtual image of the brightlines 'floating is space', and a front element. The three elements are in fact a lens and I found this lens to be noticeably negative, so much so that my old eyes were unable to accommodate the image and it appeared slightly blurry even with my glasses on. I extracted a +1 dioptre correction lens from an old SLR attachment and fitted it to the inside of the first element. I used a 1 mm wide double sided foam tape down each side. This did the trick. The middle element is strongly curved and yet fits into a straight sided groove. I found it 'rocked' slightly and this was apparent as a slight 'brightline jitter' as I moved the camera about. I pressed some Blu-Tack into the top of the groove and this kept it fixed. Problem solved. Both these modifications can be seen in the attached photo. By chance I then found a Leica 35mm viewfinder. Its similar to a 28mm Leica finder I already have (which is superb) so I was confident it would be OK and bought it. How do they compare? The 'Owl' viewfinder image is big, I would guess close to 1:1 based on a comparison with my Olympus OM-4 (which has a 0.85x viewfinder) fitted with a 35mm lens. The Leica is less, maybe 0.7x. The Leica image is very bright and the Owl is bright enough. Also the Leica image does not require any correction (this is also the case with the 28mm viewfinder). The most important difference is that Leica has very bright brightlines but the Owl brightlines can be a little faint. All in all I could live with the Owl but much prefer the Leica. I also acquired a Voigtlander 35mm viewfinder. Like the Owl it also needs a +1 dioptre lens to accommodate my old eyes but since I could see no way to fit it securely, I did not pursue this avenue.

 

[davidnewtonguitars]

I built one of the Metrocase finders from Shapeways also. Did you know the designer of it is here on RFF regularly? For my eyes it works wonderfully, I wear glasses but don't, if I am shooting this finder.
Since I prefer the M2, no external finder needed, I only mount this finder on the Leica II when necessary, I like how the base is thick and mounts securely. I think all-up it cost $35 to make.

 

[presspass]

I have at least three, and at age 73, need them. The smallest is the Cosina metal finder; in between is the Cosina plastic finder; and the biggest is a Zeiss finder made for another brand but is a 35. The Zeiss is really nice, but partially blocks the shutter speed dial on my IIIa, so I usually go to one of the Cosina finders. All are bright line and all fit the shoe as long as I put a slip of paper under the finder. None rock or otherwise misbehave. Unfortunately, they are pricer than when I bought them. Supposedly there was an Olympus finder made for one of their cameras that works well, but it's now available used only for less than $100.

 

[jcb4718]

The Shapeways/Metrocase DIY finder certainly does the job and as you say, David, its very cost-effective. I think the Leica 28 and 35mm finders have the same optics -the image looks he same- just the 35mm brightline rectangle is smaller and so crops the image more. Also, I think the reflective frame around the inner element (which back reflects the brightlines) is thicker. It tends to form a silhouette (against which the brightlines stand out) and this is more pronounced in the case of the 35mm. I have not found a brightline finder for 50mm that I could use while wearing glasses. None had enough eye relief. The closest I have come is the Voigtlander Kontur which works better than you think but takes some getting used to. My main problem with it is that I have to switch from my left to my right eye when I go from landscape to portrait. I prefer the Leica SBOOI finder and have attached a (-3 dioptre) lens on the back to correct my eyesight. My astigmatism I have to live with, its still a very nice 1:1 image.