benmacphoto
Well-known
Hello, I am still getting used to my Leica IIIa, and I was wondering if there was a M bayonet to M39 adapter? I have seen M39 to M adapters but nothing for me to put an M lens on my IIIa. Are there any step up adapters? Thanks
Roger Hicks
Veteran
No. The M-serie was made 1mm slimmer than screw Leicas in order to make adaptation easy. For obvious reasons, adding -1mm to a screw Leica is not feasible...
Cheers,
R.
Cheers,
R.
benmacphoto
Well-known
http://cgi.ebay.com/Adaptor-M42-Pen...ryZ30030QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Is the M42 mount universal or does it vary say from Pentax to Zeiss? Because if it is universal that would be very nice to have that option. And I am assuming it is not rangefinder coupled?
Is the M42 mount universal or does it vary say from Pentax to Zeiss? Because if it is universal that would be very nice to have that option. And I am assuming it is not rangefinder coupled?
Stu W
Well-known
I think Tom Abrahamsson has a black Rigid Summicron that was custom converted from an "m" mount to ltm mount. Maybe he can post some pics? Stu
Luddite Frank
Well-known
benmacphoto said:Hello, I am still getting used to my Leica IIIa, and I was wondering if there was a M bayonet to M39 adapter? I have seen M39 to M adapters but nothing for me to put an M lens on my IIIa. Are there any step up adapters? Thanks
When E. Letiz came out with their M series RF cameras and new bayonet-mount lenses, their marketing folks had a bit of say in how things were designed... they made sure that screw-mount lenses could be adapted to the new camera (so as not to render the older lenses completely obsolete), but they did not want folks to be able to put the new lenses on their old screw-mount bodies... thus helping to encourage Leica users to trade their LTMs in on the new M-body... at least, that's what I've been reading in several places on the Web...
BUT, you can buy a wonderful variety of new Cosina-Voigtlander lenses in Leica Screw-mount, as well as finding vintage lenses by Zeiss, Nikkor, Canon, Minolta, and others outfitted with the E-39 Leica Screw Mount... so you should not want for lenses to go on your LTM.
Also, I believe the design of the M-series cameras & lenses are such that even if you could stick an M lens on a screw-mount body, the glass would be too far away from the film-plane for proper focusing.
LF
rxmd
May contain traces of nut
Actually everything else would have been really difficult. If lenses of mount A are supposed to screw into bayonet B somehow, it's a bit of an engineering challenge to make B lenses fit A as well. I mean the bayonet has to be wider (so that the lenses fit in) and deeper (so that an adapter fits between the two). It's hard to design a mount that works both ways. This is an engineering problem, not a marketing decision.Luddite Frank said:their marketing folks had a bit of say in how things were designed... they made sure that screw-mount lenses could be adapted to the new camera (so as not to render the older lenses completely obsolete), but they did not want folks to be able to put the new lenses on their old screw-mount bodies... thus helping to encourage Leica users to trade their LTMs in on the new M-body...
The only way I could imagine this to work would be by making all the new lenses screw mount with an adapter. Leica actually put out a lot of screw mount lenses after the M line was introduced, so this was exactly what they were doing.
Philipp
Luddite Frank
Well-known
I'll have to see if I can find the site that "blamed" Leica marketing for non-backwards compatibility of the bayonet lenses...
I'm not doubting that there are engineering challenges...
LF
I'm not doubting that there are engineering challenges...
LF
ZorkiKat
ЗоркийК&
benmacphoto said:http://cgi.ebay.com/Adaptor-M42-Pen...ryZ30030QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Is the M42 mount universal or does it vary say from Pentax to Zeiss? Because if it is universal that would be very nice to have that option. And I am assuming it is not rangefinder coupled?
Here's another one, and slightly lower-priced:
http://cgi.ebay.com/NEW-ADAPTER-M42-TO-LEICA-L39-SCREW-MOUNT_W0QQitemZ150182099029QQihZ005QQcategoryZ30059QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
I have one. It is rather effective. But the use of these sort of adapters is fairly limited:
1. There is no rangefinder coupling, so focusing is limited by using the lens' distance scale.
2. Scale focusing is critical with long focus or wide aperture lenses. Therefore wide angle (around 28mm or shorter) lenses or slightly longer lenses stopped down are the ones which can be satisfactory to use.
3. Distance must be measured carefully if wide apertures or longer-than-wide lenses are to be used. Cumbersome, if a tapemeasure or separate rangefinder is used.
4. The larger M42 lenses will make your RF outfit bigger and heftier. That cancels out one of the reasons for going RF- i.e, going light and compact.
On the plus side, the M42 SLR to Leica M39 adapter allows the use of inexpensive wide angles on the Leica or any LTM RF. SLR M42 28, 24, 20, and even 16mm lenses often sell for less than their dedicated-for-RF equivalents. And with careful focusing, even zooms can be used.
The M42 screw mount was at times called the 'universal' mount. It was introduced by Zeiss for their Contax SLR, and was adapted by several other camera makers from Pentax to Zenit (KMZ). All of these were cross-compatible.
Here are two examples:
Russian Mir-20 20mm used on a Leica IIIc

Another one, not on a Leica, but a digital Epson RD-1s. The same 20mm lens adapted, as a cheap alternative to pricey 20mms. The smaller sensor gave and equivalent 28-30mm view.

Jay
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