Rangefinder camera discussion thread

defektive

Veteran
Location
Tasmania, Australia
Name
Sam
There currently seems to be a bit of interest in the humble old rangefinder around these parts so I thought I would start a general discussion/Q&A thread for gurus like Brian to post their pearls of wisdom in ;).

My topic to kick things off is to do with close focus ability. This is the main drawback for me when using a Leica M, the inability to accurately focus below 0.7m or 1m depending on lens used. I know some third party lenses allow nearer focussing but as far as I know that can only be done by guess work, the Leica rangefinder mechanism won't focus below 0.7m.
1) Can the Leica cameras and lenses be adjusted to focus closer than this?
2) How do other rangefinder camera brands work? Are they the same as the Leicas in this regard?

Cheers,
 
So,

There are a couple of M-mount lenses that have a close-focus capability through attachments, specifically the beautiful Close-Focus (or "Dual-Range") Summicron 50mm f2.0 and the 90mm Elmar-M f4.0. The latter is a current, collapsible lens (the only one in the range since the sad discontinuation of the 50mm Elmar-M. Both have attachments. In the case of the 50, it is a pair of "spectacles" that attach to a flange on the top. Simultaneously the focussing barrel can be moved past a detent into a close focus range. The 90mm works slightly differently in that its attachment is spectacles plus a short extension tube.

In the past there were other solutions for those wanting to go closer. The delightfully named NOOKY and NOOKY-HESUM attachments worked on the same principle as the modern 90, with a mount and an optical aid. They worked with 5cm Elmars. The other approach was to use the VISOFLEX system. This was a development of the original PLOOT and consisted of a mirror housing and a viewfinder, effectively turning the LTM or M mount camera into a somewhat cumbersome SLR. The VISOFLEX came in three iterations (I, II, III) with the latter being the most sophisticated, taking M Mount lenses and with a removable prism that could be swapped for a right-angle or chimney type viewfinder. A range of lenses were designed specifically for the Visoflex (EG TELYT-V lenses for telephoto work and a fine 60mm for macro), for both macro and tele work and many of the lenses at the time had removable lens cells that could be remounted into new focussing mounts for use on the VISOFLEX in order to maintain focal length (if this was not done the film plane to lens length changes with a concomitant impact upon focussing and the ability to reach infinity.) The VISOFLEX III can still be used today, on the current M7 and MP and (I think ) on the M8 and M9; the III is slightly taller than its predecessors meaning that the higher top-plate on cameras post-M6 can be cleared.

Leicas and other rangefinders cannot be adjusted to focus closer; the rangefinder mechanism is not suited (due to parallax correction) to be used in the really close range; similarly the rangefinder effective base length (EBL) dictates focussing accuracy with very long or very fast lenses; that's why I use .85 magnification M7 and MP, because I am not a big wideangle fan. It's also why the longest "native" focal length that Leica have supplied is the 135mm; the 2.8 version, now discontinued, was equipped with spectacles to improve focussing accuracy but it was a heavy beast of a lens. Contax had a longer EBL so did offer a 180 but it was an exotic choice.

Other brands? Contax, Nikon and undoubtedly others had an equivalent to the VISOFLEX, or just didn't bother to cater for the macro market. Bear in mind that the Leica was, from the outset, a sophisticated system camera with "bolt-on" capabilities that helped to make it into the popular success that it was.

All this is from memory, btw - E&OE ;)
 
Last night I opened the back of the Zorki 3M to watch where the RF Follower loses contact with the Nikkor 5cm f2 lens. 3Ft is the answer, the follower hits the threads of the lens. That is why M-Mount lenses have cut-outs on them, so the Cam follower can move inside the lens- past the mount. At 0.7m, the follower has traveled well into the lens. It's just geometry of the Cam follower moving from infinity to 0.7m- that is a long distance in a small space. The cam follower (Wheel on a Leica) is attached to an arm, that swings a prism.

You can make a rangefinder for close-up work, so the movement is "shifted" from close-up out to a few feet. Dual Range lenses "Cheat" by providing optics to shift the rangefinder's effective range, and move the optics of the lens out from the camera.

Easiest way to get "close-up" results with a Leica or other interchangeable lens RF camera: use a longer focal length. Telephoto lenses tend to focus to 3ft, an RF lens often will focus closer than the same version on SLR mount. Why? The short film-flange distance means the same telephoto lens on an RF camera must be physically longer to keep the optics in proper position than the same lens on an SLR. On a Leica- the lens gets about an extra 20mm for the focus helical, means it can accommodate more travel.

Nikkor 10.5cm F2.5 on the M9:



However: Rangefinder cameras need accessories on them for close-up work. "Viso-Flex" devices turn them into SLR's. Close-up lens sets "auto-up" and others provide optics to shift the rangefinder's working range and the working range of the lens. Easier to use an SLR for a lot of close-up work.
 
The easiest way, is to buy a vintage SLR to go with the vintage rangefinder, a used Nikon F with a macro lens is not only a better and more elegant solution than any visoflex housing but it is also a lot cheaper
 
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