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Explore the world of vintage lenses through repair notes, real test shots, and detailed archive threads packed with images.

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Help Me Identify the Mount?
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Hi guys,
anyone know what mount is this? The lens is telemegor 400/5.5. Box says exacta but when comparing to pictures for exacta mount, bayonet seems to not match. (Apologies for crappy pics btw).





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Exakta external flange mount.
Exaktas had an inner bayonet, which is the usual mount, but also an external flange for large and heavy lenses.
The external flange mount has no common adapters. I have had to make my own.


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+1, I had one as well. A ISCO 180mm f/2.8 with external Exacta mount...


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Thanks Luis.

Any ideas how to mount it to nex?

Just found better image on ebay showing the mount
http://i.ebayimg.com/00/s/MTIwMFgxNjAw/z/H-QAAOSwLa9UXjhe/$_57.JPG


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Several ways.
One likely one is to pick up a proper old stock Exakta lens mount ring on ebay. I have seen them fairly often. These are available as spares for Exakta as they are easily replacable on the cameras.
Failing that an old broken Exakta will give you a mount quite easily.
With some drilling and filing you should be able to take an Exakta-Nex adapter and modify it with the proper Exakta mount. If there are thickness issues (Exakta mounts being fairly thick) you may want to look at a Next adapter with a shallower register, such as Canon.


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Other things to look into -
The mount on this lens is interchangeable, it is possible to obtain a different "cone" back section.
AFAIK these aren't that common but I have seen them around. I don't know whether they are interchangeable with each other - is, if one that was meant for a Meyer Orestegor would go on your Telemegor, etc.
The mount plate on your lens looks like it may be removable. If so it may be possible to take a flanged adapter with a narrow throat (not sure what would work) and just drill the corresponding screw holes.

What I did for Pentax was to use such a flanged PK-M42 adapter though I had to drill and tap screw holes to suit, as the throat of that mount is rather large and does not permit use of the existing screw holes.


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Perhaps a dumb idea: if i were to pickup regular exakta to nex adapter (like this one: http://i.ebayimg.com/00/s/NjAwWDYwMA==/z/8ZcAAMXQoYJSIAtg/$(KGrHqZ,!nwFIJ(N1SZ)BSI!tgseug~~60_12.JPG),
remove all the aperture engaging mechanism, and reverse the exa mount so that internal bayonet will be on the outer side - will it work?


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Link is bad.
No, the bayonet on the regular exakta adapter can't be made to fit.
Look at actual Exakta cameras for pictures of the external bayonet flange.


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luisalegria wrote:
Link is bad.
No, the bayonet on the regular exakta adapter can't be made to fit.
Look at actual Exakta cameras for pictures of the external bayonet flange.


My bad, here is the picture of the adapter.




What models of exakta cameras have external bayonet flange?


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Almost all the proper Exaktas, except for the very earliest.
Have a look, you will see what I mean, pictures are worth more words than I can write in my #$$&& android thing with @$%& keyboard.
Not the little Exas either.


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luisalegria wrote:
Almost all the proper Exaktas, except for the very earliest.
Have a look, you will see what I mean, pictures are worth more words than I can write in my #$$&& android thing with @$%& keyboard.
Not the little Exas either.


Yup, figured it out, saw the pics of external flange exaktas. Thanks.


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http://www.heritagecameras.co.uk check link out, I always look here first as they tend to have some weird stuff lol


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I think this is what Luis is on about, the conical adapter that screws onto the back of many lenses from M.O.G. and Pentacon, the lens in the picture is a Pentacon 135 but the loose mount is Exacta, the thread and location on the lens is identical, it's just the cone that differs - in this case Exact and M42.





The Exact mount.


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Thanks Luis & Lloydy,

I'll check if the cone of the lens can be unscrewed. If not, i'll hit the store for damaged exakta and see what i can do with it.


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OK, so i was able to find (purely by accident) heavily beat up exa II with double bayonet mount and CZJ tessar on it. Tried telemegor on it, and obviously perfect fit. So Exakta to Nex adapter is also on the way and should arrive in few days. I hope the double bayonet mount will fit the nex adapter without much drilling and filing.


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Good luck


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luisalegria wrote:
Good luck


Thanks and thanks again for all your guidance. Wink
Much appreciated.


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OK, exakta to nex adapter has arrived, but it's a no go. Exakta double flange mount (from exa II) won't fit the adapter: screw holes are too far apart and the double flange mount is too narrow to fit the adapter. so at this point i'm left with only option to replace the actual cone with mount on the lens. Found this: http://www.ebay.com/itm/PENTACON-MEYER-Rear-M42-Mount-Tube-for-300-400-500-Lens-CANON-ARRI-NIKON-/371179154242?pt=US_Lens_Adapters_Mounts_Tubes&hash=item566c006b42

Bit pricey, but i guess it'll have to do.


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Just in case someone else has same problem like this with Telemegor 400/5.5 - cone replacement does not work - I bought m42 cone as in link in previous post and my Telemegor (same back end as in first post) can unscrew cone part but I don't know if it is on older/newer versions or something but cone part is different and does not fit... so for me back to the drawing board. I will try to put some pictures in next few days, but just wanted to warn others so they don't throw away money on cone before they check what cone type they have...


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mmatko wrote:
Just in case someone else has same problem like this with Telemegor 400/5.5 - cone replacement does not work - I bought m42 cone as in link in previous post and my Telemegor (same back end as in first post) can unscrew cone part but I don't know if it is on older/newer versions or something but cone part is different and does not fit... so for me back to the drawing board. I will try to put some pictures in next few days, but just wanted to warn others so they don't throw away money on cone before they check what cone type they have...


the Telemegor cone measures 75mm across and the only ones I've seen for sale are 72.5mm and are for the Orestegor and Pentacon, I've been looking for a long time to find someone selling a M42 cone to fit my Telemegor with no luck lol