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01-30-2010, 08:21 AM   #31
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QuoteOriginally posted by MattGunn Quote
If you can get the focus ring off easily then you should find a friendly local model engineer to machine the focus ring back. It would only take a few minutes on a lathe but it will take hours to sand it back by hand.
Thank you guys so much for the quick replies!

How many m.m. do you think needs to be sawed off?

I'm trying to use the lens on a Nikon D90 body with an M42 adaptor that retains the infinity focus (somewhat) - I already have a bleeding finger from trying to unscrew the lens from the M42 adaptor ;(

I just stepped into the DSLR world from my little point and shoot so please excuse my questions if they are common knowledge. I did google around a lot but didnt find any answers except here in this forum.

Best Regards,
Hari

01-30-2010, 12:19 PM   #32
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QuoteOriginally posted by Hari Quote
Thank you guys so much for the quick replies!

How many m.m. do you think needs to be sawed off?

I'm trying to use the lens on a Nikon D90 body with an M42 adaptor that retains the infinity focus (somewhat) - I already have a bleeding finger from trying to unscrew the lens from the M42 adaptor ;(

I just stepped into the DSLR world from my little point and shoot so please excuse my questions if they are common knowledge. I did google around a lot but didnt find any answers except here in this forum.

Best Regards,
Hari
You are very welcome to whatever help we can give you, even if you do shoot Nikon

You have two problems:
  • The weird focus ring
  • Infinity focus on the Nikon
The focus ring can be sanded, ground, or machined down. The distance is not very much (a few millimeters) and can be measured by noting the offset from the actual mounting flange. I would probably go as far as the start of the knurling.

As for infinity focus...Nikon cameras have an infinity focus registration just a little bit more than that for M42 (+1.0mm). As a result, M42 lenses do not adapt to Nikon without an auxiliary optic on the rear of the adapter. Unfortunately, that optic often results in image degradation. Solutions vary according to the lens in question. On some lenses (e.g. Zenitar 16/2.8), infinity "run-out" is easily adjustable according to the position of the focus ring itself. This is may be the case with your Helios 44-3. If the "stop" is part of the focus ring, you should be able to simply reassemble the ring so that the index is a little shy of the infinity mark. It will take some trial and error, but might work. (It helps to confirm the infinity focus using a film body with a split-image finder as a reference.)

Again, any other forum members are encouraged to add their advice!

Steve

Last edited by stevebrot; 01-30-2010 at 12:49 PM. Reason: Corrected grievous error...
01-30-2010, 02:04 PM   #33
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I want to take as second and thank you, Steve, for this important thread. I have been on the fence about getting one of these lenses, for a long time. I heard about some issues coupling the body to the lens, along with lens wobbling in "successful" mounts. Up to now, I have avoided the purchase, simple because I did not feel confident enough in my understanding of the lens to make that purchase. But this thread, especially with the augmenting it gets from other great posts, (Mel & George, for example) gives me the knowledge I need to proceed with a successful purchase.

Thanks to all!
01-30-2010, 03:31 PM   #34
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QuoteOriginally posted by Jewelltrail Quote
I want to take as second and thank you, Steve, for this important thread. I have been on the fence about getting one of these lenses, for a long time. I heard about some issues coupling the body to the lens, along with lens wobbling in "successful" mounts. Up to now, I have avoided the purchase, simple because I did not feel confident enough in my understanding of the lens to make that purchase. But this thread, especially with the augmenting it gets from other great posts, (Mel & George, for example) gives me the knowledge I need to proceed with a successful purchase.

Thanks to all!
My pleasure to be of service!

Steve

03-18-2010, 02:01 PM   #35
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I got one of these 44-3 cheap. It works with the pentax m42 adapter, but it makes the focus ring hard to move and wont focus to infinity.

So... Next step is removing the focusing ring and grind it down a bit. Have anyone tried this? If so, what did you do, and did it work out alright?

Oh, and I assume you only loosen the tiny tiny screws in the focusing ring to remove it before grinding. Correct?

All advice would be appreciated.
03-18-2010, 02:36 PM - 1 Like   #36
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QuoteOriginally posted by Hari Quote
I already have a bleeding finger from trying to unscrew the lens from the M42 adaptor ;(
Hint: Don't apply or remove adapter with fingers. Use a rear lens cap as your 'wrench'. Less blood gets into/onto the machinery-floor-table-etc that way.
04-25-2010, 06:34 PM   #37
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Hey guys - I just bought an 44-2 and I'm having the tight focus ring issue as described in here. It's an 89xxxx model so I thought I just shared the information here.

You can find out more here
04-26-2010, 09:45 AM   #38
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QuoteOriginally posted by ducdao Quote
Hey guys - I just bought an 44-2 and I'm having the tight focus ring issue as described in here. It's an 89xxxx model so I thought I just shared the information here.

You can find out more here
Thank you Duc for sharing this. I read your original posting on the other thread and was extremely surprised. Your 44-2 is of fairly recent manufacture and appears to share the same body as the troublesome 44-3. Who would have guessed?


Steve

04-27-2010, 11:17 PM   #39
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QuoteOriginally posted by stevebrot Quote
Thank you Duc for sharing this. I read your original posting on the other thread and was extremely surprised. Your 44-2 is of fairly recent manufacture and appears to share the same body as the troublesome 44-3. Who would have guessed?


Steve
Hi Steve, I looked closely at my Helios again and the gap between the mount flange and the focus ring is extremely minimal, not even visible to the eyes. One thing for sure is once installed on to the M42 adapter the focus ring touches the M42 adapter which causes the friction hence makes the focus to be painful. I guess I have take off the focus ring and grind it a little bit, perhaps 0.5mm
11-18-2010, 07:25 PM   #40
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I just purchased a 44-M4 M42 in what I HOPE to be in good condition on ebay. The seller has a good rep and says the lens is clean and was built in 1990... beyond that I won't know until I see it in person. As I am entirely new to this whole world, I was wondering if anyone had any recommendations as for what to do - as in pentax mount vs. 3rd party mount, also - any recommendations for filters?
11-18-2010, 10:00 PM   #41
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You want the first-party M42->K adapter.

I don't know why you'd want to use filters, but there're plenty of explanations of those out there.
11-19-2010, 01:06 AM   #42
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For completeness sake it might be noted that also other lenses show this problem.
E.g. the Mamiya Sekor SX M42 lenses, at least some of them, have this protruding ring.
11-19-2010, 02:53 AM   #43
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QuoteOriginally posted by blende8 Quote
For completeness sake it might be noted that also other lenses show this problem.
E.g. the Mamiya Sekor SX M42 lenses, at least some of them, have this protruding ring.
Yep! Got a 135mm Mamiya Sekor with this problem!
11-19-2010, 03:54 AM   #44
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QuoteOriginally posted by Rense Quote
Yep! Got a 135mm Mamiya Sekor with this problem!
Same here, but mine won't even MOUNT.

Gonna have a friend grind it down for me.
11-19-2010, 09:26 AM   #45
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As an engineer I have mounted a complete lens in a lathe and turned a section of damaged filter thread off the front that was too damaged to be repaired by the usual methods.

I wrapped the lens in one wrap of 50mm wide insulating tape and very gently mounted the lens in a 3 jaw chuck, and at a very slow speed ( alluminium usually requires a fast speed ) and a very sharp carbide tipped too I turned a bit off the lens.

The old Rikenon 135 didn't suffer any damage at all from being spun up in the lathe.

A good machinist would tell you if they were confident of doing the back end of a Helios.
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