cassel
Well-known
I've been trying to find out how the accessory/auxiliary lens sets from the late 50's through 70's (?) work. Some are brand name sets that seem specific to certain cameras/lenses - others are secondary brands (like Vivitar and Vemar). I understand that they either screw on (or clamp-on) to the fixed lens of rangefinder cameras.
My questions:
Is each set (usually "wide" and "telephoto") calibrated for a specific lens formula?
Or is it a simple matter of screwing on the right thread size-a universal fit optically? (like glasses/corrective lensese)
How do you adjust focus- do you have to transfer the rangefinder setting to the aux. lens?
Most sets come with accessory brightline finders....right?
My questions:
Is each set (usually "wide" and "telephoto") calibrated for a specific lens formula?
Or is it a simple matter of screwing on the right thread size-a universal fit optically? (like glasses/corrective lensese)
How do you adjust focus- do you have to transfer the rangefinder setting to the aux. lens?
Most sets come with accessory brightline finders....right?
kram
Well-known
I first must apologise for a half baked answer. The only 'experience' I have is with my fathers Contaflex (SLR). The fixed lens had a wide angle + slight tel push fit extra lens element for that particular lens. My father said they where not worth the hassle as the image quality was degraded too much.
I've had no experience with the cheaper Pantar lens model Contaflexes. But I've used, and still use, the Pro Tessars for the better models a lot. The 115mm is passable and the 35mm & 85mm perform a lot better than many people would expect. They should not be placed in the same category as the generic third party brands.
Cheers
Brett
Dwig
Well-known
The typical afocal attachment lenses were generic designs that targeted some "average normal" lens as the base prime lens. Only a few were designed to mate with a specific lens and they were always sold by the camera manufacturer.
Image quality varies. Those few high quality offerings that were designed to mate with a specific lens or narrow range of lenses can be reasonably good, though the wide angles always exhibit a bit more rectilinear distortion than a prime wide angle would. Also, the amount of FL change is generally modest.
There are often some focusing shift at closer distances. Those made for TLRs and fixed lens SLRs generally ignored this as the camera's focusing system would adapt. Those made for RFs sometimes had a translation table on the lens or in the case.
Image quality varies. Those few high quality offerings that were designed to mate with a specific lens or narrow range of lenses can be reasonably good, though the wide angles always exhibit a bit more rectilinear distortion than a prime wide angle would. Also, the amount of FL change is generally modest.
There are often some focusing shift at closer distances. Those made for TLRs and fixed lens SLRs generally ignored this as the camera's focusing system would adapt. Those made for RFs sometimes had a translation table on the lens or in the case.
cassel
Well-known
Sounds pretty hit-or-miss. Might make for an interesting experiment for a fixed rangefinder....most are pretty cheap anyway.
Ronald M
Veteran
Reminds me of my poor college days when all I had was a Waltz Envoy with 50 2.0 Nikor. I purchased a aux wide and tele set which was a total waste of money.
Pro Teasers for Contaflex were ok
Rollie Mutars for TLR are ok
Pro Teasers for Contaflex were ok
Rollie Mutars for TLR are ok
sevo
Fokutorendaburando
The afocal ones that attach in front of an existing lens are universal - these essentially are a Galilean telescope (of positive or negative enlargement) the lens peeks through. The base lens and matching kit lenses may be fine tuned for a perfect match, but the performance will nonetheless still be quite similar on any other lens of similar physical characteristics.
The ones that replace part of the existing lens (as in the case of most leaf shutter SLRs, like that Contaflex) are a matching front group to whatever rear half permanently installed on the camera. These might sometimes be theoretically interchangeable (if anybody converted them to another, highly proprietary, mount) as many of them seem to derive from the same Zeiss patent, but YMMV - others might not even be Triplet/Tessar derived but entirely different base types, and in any case, these are not afocal so that spacing is very critical and will affect the focal length and optical performance.
The ones that replace part of the existing lens (as in the case of most leaf shutter SLRs, like that Contaflex) are a matching front group to whatever rear half permanently installed on the camera. These might sometimes be theoretically interchangeable (if anybody converted them to another, highly proprietary, mount) as many of them seem to derive from the same Zeiss patent, but YMMV - others might not even be Triplet/Tessar derived but entirely different base types, and in any case, these are not afocal so that spacing is very critical and will affect the focal length and optical performance.
cassel
Well-known
Interesting- Sounds like I'm looking at the afocal type then. In layman's terms they really do sound like glasses for your fixed lens
The sets I've been considering are often marked "focus 2m(6ft) - infinity". Does this mean the focus is set and the cameras rangefinder will still work?
Mutar-- there's a great name for a lens line-up
The sets I've been considering are often marked "focus 2m(6ft) - infinity". Does this mean the focus is set and the cameras rangefinder will still work?
Mutar-- there's a great name for a lens line-up
bsdunek
Old Guy with a Corgi
The Rollie Mutars are excellent, as you might expect. Any degradation is undetectable to our eyes. My old Rollie 3.5 takes excellent photos with the Mutars.
I also have the wide & telephoto lenses for my Yashica GSN, including viewfinder. I think they work very well. I am always satisfied with the results. Of course the telephoto and wide effect are not too strong. Still, they are useful.
I also have the wide & telephoto lenses for my Yashica GSN, including viewfinder. I think they work very well. I am always satisfied with the results. Of course the telephoto and wide effect are not too strong. Still, they are useful.
cassel
Well-known
How does the focus work on the Yashica?