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Old Dec 19, 2008, 3:07 PM   #51
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HI

Can you make an accurate measurement in millimetres? I will check against one of mine (if I can find it! :lol
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Old Dec 19, 2008, 3:15 PM   #52
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John Hill wrote:
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HI

Can you make an accurate measurement in millimetres? I will check against one of mine (if I can find it! :lol
Hi John,

I posted a picture that is my lens original mount with measurement in "inches". If you convert to "cm" it's 49cm. :G
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Old Dec 19, 2008, 7:11 PM   #53
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49CM you say? Sorry I dont have any experience with lenses that size, nearest I can find is this picture of a 50cm diameter telescope, is that the sort of thing you are seeking an adapter for?











:G
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Old Dec 19, 2008, 7:43 PM   #54
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Hi John,

So sorry, I typed the wrong word. It should be 49mm, but not 49cm.

Also, I just found the measurement of T-mount's inner ring is 1.46 inches....

http://www.jmloptical.com/level2/ima...chp08/H-11.GIF

And T2 is 1.615 (41mm~) from another source. So it might not be either T or T2 mount.

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Old Dec 19, 2008, 8:03 PM   #55
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Bah humbug to them all!



I have just been photographing and measuring two T mounts I have here, one is marked 'Vivitar Series 1 T Adapter". This adapter is ONE PIECE! It has a K mount on one side and a 42mm FINE thread on the other, this thread is 0.75mm pitch and is what Tamron chose to mount their variety of adapters to lenses, this thread is the same diameter but not the same pitch as the Pentax screw, aka M42, thread used in camera bodies to mount early screw type lenses. If you have a T adapter and try to screw it onto a M42 lens the threads will be damaged. But thats just an aside as it is not the case we have with your lens.

The other adapter is from a local High Street camera shop and although branded Bushnell and called a "camera body adapter" it is functionally identical to the aforementioned T1 adapter, it has the fine thread (female) on one side and the K mount on the other.

The difference is the second one is in two pieces, there is an outer ring to which the K mount is attached and the inner ring which has the threaded interior. This inner ring has an outside diameter of 48.9mm and is held in place inside the outher ring by three set screws. In normal use these three screws are loosened and the two rings rotated in relation to each other to align the camera with the lens, for example if the lens has a tripod socket you really want that at the bottom when the camera is level!

So, what you want is one of these two piece adapters which are quite scarce for cameras nowadays but they are still made in their thousands for telescopes however you do need to be sure the one you are buying has the three set screws so that you can take it apart. When you get the adapter just loosen the screws and take out the inner ring then pop the adapter onto your lens and tighten the screws!



As far as I can tell, but I am not absolutely certain yet, the T1 and T2 adapters are the same dimensions but the T2 is the two piece one.



The drawing you provided shows a m42/0.75mm external thread and therefore describes the fitting on the back of a T mount lens, so not really applicable to what we are trying to decide.


The 41mm you mentioned is the internal diameter of a 42mm female thread, actually 40.7mm according tomy calipers.






Cheers.








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Old Dec 19, 2008, 8:56 PM   #56
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I just find out an interesting thing. If you guys ever saw Russian Peleng 8mm fisheye lense and this lens is interchangeable mount (comes with M42 and Nikon AI mount). I have this lens that comes with an interchangeable mount that can put on Minolta MF camera.

After I took that mount off and put it on the lens I posted before, and that works perfectly!!!!! What amazing thing!!!!!

So, now I know I need to find this mount to put on this lens. However, I still have no idea.

But John, thanks very much.

blue
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Old Dec 19, 2008, 9:27 PM   #57
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Blue, this is the one you need for your lens...





You can see it is the one you need as it has the screws that allows you to take it apart and use just the outer part.

http://www.adorama.com/LNTMPX.html



cheers
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Old Dec 19, 2008, 9:33 PM   #58
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thanks John......

But do you know the measurement of the inner part of the outer right? If I know about that, that will be awesome!!!
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Old Dec 19, 2008, 9:38 PM   #59
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49mm, you see that piece with the writing on it? That is the piece that comes out when you undo the three screws and the space that is left is 49mm.
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Old Dec 19, 2008, 9:44 PM   #60
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Yeah!!! That's great!!!!
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