Help me identify this lens mount, please.

<p>This is a lens that I have found and cannot tell what camera it is for. I am not even sure if it is for an SLR or not.<br>

The lens is a 35mm f/2.8 Mosler Photoguard. For some reason the white lettering of only the name was painted over. It has a few peculiar features. First are two aperture rings. One on the outer part has click stops from f/2.8 - 22 and the inner one is labeled the same but when you have the putter ring stopped down to 22 the inner one smoothly opens up the iris all the way to 2.8 and can stop anywhere in between. Also it is not an auto aperture; there is no pin or lever to open it for wide open focusing, this is one reason why i think it might be some kind of movie lens. Also the distance scale on the lens is marked down to 24". included are some photos of the mount. It appears to have a hole in the mount side , might be missing a mount locking pin; also there's a pin on the barrel on the mount side.<br>

Also when i got it on the rear was a cap labeled ISCO but it looks like it could be a front lens cap that was just used for the rear.<br>

Does anyone out there have an idea what this is for ?<br>

<img src="http://i86.photobucket.com/albums/k95/napolitan_2000/108_2248C.jpg?t=1302384541" alt="" width="603" height="639" /><br>

<img src="http://i86.photobucket.com/albums/k95/napolitan_2000/Lenses/108_2251C.jpg?t=1302383807" alt="" width="616" height="639" /></p>

<p>I also have a link to a video looking at the lens with the sound track that is appropriate i think :-)<br>

http://www.youtube.com/watch?v=LkPC_Qb-hPg</p>

<p>Sure looks like an Exakta bayonet mount. The two aperture rings indicate that it is a "preset" lens. YOu set the shooting ap before you take a pic, and set the detented ring where you want it. Then just before shooting, but after you have focused, you turn the other ring to get the preset ap.<br>

Larry</p>

<p>That's almost certainly a preset Exakta/Topcon mount, hence the two aperture rings. </p>

<p>Thank you both very much. I have never had any experience with this mount so that's why the 2 aperture ring setup confused me. Also i always thought that preset lenses had fixed apertures that were preset and could not be adjusted; like how everyone always calling my mirror lens a preset lens.<br>

Well , now that i know the mount and since i have no camera that this would fit i guess i should probably try an sell it. It doesn't strike me as anything particularly special. Ever hear of the lens brand tho? AN internet search didn't turn up anything photographic by this name.</p>

<p>The two aperture rings do not suggest Exacta in any way, shape, or form. As was already correctly stated, it's a preset aperture. It has absolutely nothing to do with the lens mount. I have preset Helios 44 lens in M39 screw mount and there are many others in M42. They generally predate automatic aperture lenses. What this lens mount is however is beyond me. Isco made lenses in Gottingen, West Germany, but your lens is made in Japan.</p>

<p>I suspect that this lens may have a T-2 mount that unscrews and allows you to fit a mount for whatever camera you have. Try turning the knurled area nearest the mount, anti-clockwise. T-2 mounts are still fairly easily obtainable.</p>

<p>That could be a T2 mount. Before turning the aft knurled ring, you'll probably have to loosen a two or three set screws in the side of the mount. Those screws lock the mount into the threads.</p>

<P>The only listing under Mosler in the LVM is this:</P>

<BLOCKQUOTE>

<P><STRONG>"Mosler There are no details about this f2.8/35mm lens. an early retrofocus for Exakta. It may be a dealers trade name."</STRONG></P></BLOCKQUOTE>

<p>My first response wasn't worded very well. As Rob Holz says, the aperture rings have nothing to do with the mount; they only indicate that it is a preset diaphragm. It's still an Exakta or Topcon T2 mount, though.</p>

<p>I see a white s[ec that could be a pin as on a ys, which is a automatic t mount<br>

but it is very hard to see if the mount has lugs ( bayonet) or is a thread<br>

BUT a YS lens would NOT be a preset and have two aperture rings<br>

I think you need more photos.<br>

from what information we have it may be just a guess</p>

<p>It is IMHO a T mount lense. It's made in Japan. Most T mounts are preset and if YS would not be preset. Also assuming this is for Exakta most Japanese brand would be preset T mount, and Exakta had a side mounted shutter release would require a special adapter. There are side mount release YS adapters but the lenses were not preset but rather automatic and with T mount thread(42mm fine thread) and registration (55mm lens to film plane).</p>

<p>I agree that it's an Exakta mount and a T mount that should unscrew. No need to loosen the set screws; the set screws are for adjusting the mount so that the lens is oriented correctly on the camera with the aperture scales visable from the top.</p>

<p>Hahah, you wonderful ba$%#&ds. It is indeed a T-mount lens with an Exakta adapter on it. It unscrewed so very easily. I am ashamed i did not realize it earlier; and since I already have a T-mount Mirror lens I can borrow t-mount adapter off that and try out this lens on my minolta, or the G1 I will be using next week.<br /> I am curious as to the quality of this piece of glass.I will try a roll of B&W film first, then a color roll.<br /> Again Thank you all :) I did have more photos of this lens but i guess there is no point of me posting them now.</p>