40mm F4.5 LTM lens?

[zhang xk]

Hi folks,

It has been a while I did not introduce some idea of DIY items. Here is a 40mm F4.5 sharp lens in ltm mount. The lens was removed from an early Smena so that it could be a Zeiss 3G/3E lens, and it is a sharp lens. The lens mount is from a very worn J-8. Now this 40/4.5 lens is mounted on a Zarya for scale focusing and it can focus to infinate.

I tested this lens on a Canon 300D as a macro lens. The image is a 100% crop of the full frame and was shot at F8 at about 40 cm. Although it is only a 3g/3e simple lens, it is very sharp.😀 :bang:

Cheers,

Zhang

 

[nzeeman]

can you explain procedure for making this - i would like to try to make that also. it looks like fun and its a great idea.

 

[Nickfed]

Surely not that great an idea. The focussing scale on the barrel is for a 50mm lens and therefore would make little sense when the 40mm lens replacing it is moved by the same amount.

Or has a new pair of threads been cut?

 

[zhang xk]

Surely not that great an idea. The focussing scale on the barrel is for a 50mm lens and therefore would make little sense when the 40mm lens replacing it is moved by the same amount.

Or has a new pair of threads been cut?

Ha, I will paint the barrel black and engrave a new set of distance scale. The helical threads are fine.😉

 

[zhang xk]

can you explain procedure for making this - i would like to try to make that also. it looks like fun and its a great idea.

Hi Thanks! If you have a dead Smena 2, you can remove the lens group easily from the camera. Then remove the lens group from a useless J-8, remove the two screws from the J-8 lens that limit the the front parts movement so that the front component can move closer to the camera that will be suitable for the T-22 lens group for infinate focusing. Put the T-22 lens group into the barrel of the J-8 and make it stay fast. Then check the focusing with a ground glasss.

A Russian Zarya is a suitable camera for this lens. The camera is light and durable for less parts, and it is a nice street rangefinder camera.😀

 

[Trius]

Nick: When someone uses their ingenuity, takes some old stuff and makes a camera that can make a good image and is FUN to use ... how is that a bad thing?

 

[w3rk5]

Very kewl Zhang. 😎

 

[Nickfed]

Aha, Zhang. I guess that's a better idea than re-cutting the threads!
And I smell some close focussing coming over the hill. I believe it should focus at about 600mm when against the 1m stop.

 

[Nickfed]

Nick: When someone uses their ingenuity, takes some old stuff and makes a camera that can make a good image and is FUN to use ... how is that a bad thing?

Without the re-worked focussing scale Zhang later alluded to, I assure you it would be very little fun.

 

[zhang xk]

Aha, Zhang. I guess that's a better idea than re-cutting the threads!
And I smell some close focussing coming over the hill. I believe it should focus at about 600mm when against the 1m stop.

Hi Nick, I just checked the distance scale of the I-50. It is very accurate with the T-22. So, no re-painting and no new scale.😀 A scale focusing lens is not good for critical close focusing. But if you insist, I-50's 1.5 meter scale is about 1 meter for the T-22. For street shot, just use great DOF.

I believe it is a much better idea than re-cutting the threads.🙂

 

[Nickfed]

Indeed it is much better than new threads but I think you should check the maths. I submit that at "1.5m" the T-22 will focus at 882mm BUT I guess for this sort of stuff you wouldn't bother focussing so close anyway, and guessing about 30% short is something you will get used to!

 

[zhang xk]

Here is another close-up test image. It is indeed a very sharp lens. The 1st image is a 100% crop without PS. On a Leica M8, it is a nice little 52/4.5 lens.

This is for fun. These are dirt cheap items, so don't be too serious. I do not recommand destory a good camera and a I-50 for this.

 

[nikola]

nice, i could try this if i find parts 🙂

 

[zhang xk]

nice, i could try this if i find parts 🙂

A correction! The lens mount is from a J-8, not an I-50. Sorry for this confusion. I have quite a few parts lenses, I assumed it was a I-50 lens mount.😱

 

[zhang xk]

Here is another close-up test image. It is indeed a very sharp lens. The 1st image is a 100% crop without PS. On a Leica M8, it is a nice little 52/4.5 lens.

This is for fun. These are dirt cheap items, so don't be too serious. I do not recommand destory a good camera and a J-8 for this.

The point is that the T-22 is an in-expensive but very sharp lens with a very useful focual length. It is a pity it was not made in LTM mount.🙁

Now the 100% crop image with a little PS. How much sharpness do you really need?🙂

 

[nzeeman]

this looks very veeery nice. i must try when i find some broken cameras.