adapters for exakta outer bayonet?

[taunusreiter]

Are there any adapters for Exakta (Topcon) outer bayonet mount available, to get them working on a NEX?

I just see adapters for the older inner bayonet mount (see for the difference: http://www.wrotniak.net/photo/exakta/lenses.html )

Thanks

[Attila]

I never seen ever except if DIY made.

[Sevo]

Not that I know of. But in most cases that should be easy to work around, the outer bayonet was only used on long lenses and these generally had workshop-replaceable adapter barrels at that time. In most cases it will be Meyer tele lenses, whose adapter tubes can be replaced with Exakta inner, P6, M42 and probably some more. Spares (in particular Exakta inner and P6) often are offered on ebay. Even if it should be a more fancy lens, anybody with a lathe could make a suitable adapter from a extension ring and a bit of brass barrel...

Oh, and while we are at it: Have any Topcons got the outer bayonet?

[scsambrook]

[iangreenhalgh1]

My 135 and 200mm Topcons have the inner bayonet. Same with my Meyer 4/200.

[luisalegria]

I made my own Exakta outer-PK adapter, for a Meyer 300/4.5 Telemegor

Base was a flanged M42-PK adapter. I used a dremel tool to grind out slots for the lugs on the lens, and drilled countersunk holes for screws. I just unscrewed the screws on the mount and screwed them through the holes on the adapter. It fit flush due to the slots.

[bob955i]

FWIW I've had a look at both my P6-Exakta adaptors - one is an early type with the all alu lock ring and the other with zebra lock ring and they both have the outer bayonet. None of my 135-200mm Exakta lenses from CZJ, Meyer or S-K have the outer bayonet.

[taunusreiter]

I thought the outer bayonet mount would been more common, since Ihagee launched it as early as 1953, and the inner bayonet is that narrow to make it unusable with higher speed lenses of a certain focal length.
I have a lens here which back element barely fits through the lens opening, you wouldn't even consider it would fit to the inner mount.



My only Exakta lens adapter so far is for Olympus Pen F/FT cameras.
Alas, it just have inner bayonet. But I have seen Exakta lens mount spares with outer bayonet available.[/img]

[Attila]

I saw only Exakta-P6 adapter like Bob said before what do use outer mount.

[bob955i]

[luisalegria]

Few lenses seem to have been made with the outer bayonet mount.

The one you have there is one of the few, the Taisei Kogaku (Tamron) 58/1.2 often seen as a "Taika Harigon"
This is a rather uncommon lens. I don't think Tamron or anyone else even made a T-mount for the outer bayonet.

Much more common I think were the big Meyer lenses, the 180/3.5 Primotar and 300/4.5 Telemegor, which are the ones most usually found in this mount. Strangely the 400/5.5 Telemegor, if it is in Exakta mount, seems to always have the inner bayonet, not the outer.
Maybe there are some other monster lenses with this mount also, but I think they would also be uncommon.

Anyway, what I have seen of the outer mounts on the Meyer lenses is very different from the Taisei 58/1.2. There is no ring structure around the lugs on the lens, they are free-standing. I think adapting this lens would be fairly difficult on most cameras. If I had to adapt this on the Nex I would probably look for a spare camera mount with external bayonet from a broken Exakta as Bob says, and use that to modify an EOS-Nex or Minolta-Nex adapter, the reason to use EOS or Minolta would be to give some working room for the increased depth if you attach the Exakta lens mount to the front of the Nex adapter.

[gareth12468]

I found this on the Internet..... From Hong Kong.....

Exakta to Sony NEX adapter

http://www.towerloop.com.hk/Product_Item.php?product_id=11202

[bob955i]

That adapter has the inner bayonet type mount - the OP needs one with the outer bayonet type.

Looks like the fitting of a camera mount with the outer bayonet is feasible though.

[luisalegria]

True, it looks like a real mount from an Exakta camera should just drop in to that adapter.
You'd probably have to drill new holes in the Exakta mount though.

The adapter does seem a bit expensive. Thats the going rate for Nex adapters ?

[bob955i]

A good machinist should be able to knock a suitable collar up that the camera mount and NEX adapter are screwed to.

Hardest part is attaining the correct collar height.