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12-31-2018, 08:26 AM   #1
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How to fix my Helios 44M?

I have a Helios 44M that I bought from a forum member a year or so ago. I started reading about reversing the front element of Helioses and decided to try this. Once I got things disassembled it became obvious that front element reversal doesn't work with a 44M, apparently other versions like the 44-2 have a different design that physically allows the front element to go back in backwards. Mine simply doesn't go back together if you try to reverse the front element (which is no small feat to even get to).

So... I go about putting the thing back together with a properly arranged front element. My first try, with the help of some YouTube videos gets it buttoned back up. I use all the parts. The aperture works, it's stiff but all seems fine, until I take some test shots and realize it won't focus to infinity.

Trial #2 ends up with the aperture not working. Took it apart again, messed with it for an hour or more, finally got it back together, aperture works, but it only focuses from about 1.5m to about half a meter.

What to do now? Yes, there are several YouTube videos of disassembling, cleaning, lubricating, and re-assembling the 44M. The problem is that they assume that the person doing the work had the care and forethought to disassemble the lens correctly, making careful marks and notes of exact placement of rings and the helicoid and other bits. I was not so bright. I dove in and screwed it all up.


Basically I have randomly assembled bucket of 44M parts that I would like to turn back into a functioning lens. But I don't know how to do that. Any thoughts? Buy a new lens?

12-31-2018, 08:52 AM - 1 Like   #2
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Tricky! Something like this is akin to one of those brain-teaser puzzles in which the most obvious way to reassemble the thing may be the wrong way. Solving the puzzle depends on some combination of intense mental effort to think about how all the parts relate to each other, perseverance in trying different part arrangements, and a healthy dose of luck.

But first a question: you say the lens focuses at 1.5 meter at it's furtherest. Is the image nice and decently sharp across the frame or is it unexpectedly blurry in the center and/or corners?

If it is sharp, that indicates that all the elements are in their correct relative positions but something prevents the whole assembly from moving close enough to the sensor or film plane to achieve infinity focus. That suggests an issue with how the helicoid or the focus ring are assembled together and relative to each other. Some lens' helicoids have multiple starts so that rotating the inner or outer helicoid by 180 (for a 2-start helicoid), 120 (for a 3-start helicoid), etc. gets things in the right location.

If the image is blurry, then something is wrong in the element assembly such as a misplaced sequence of elements and spacer rings or a reversed inner element. That requires mucking about with the order and orientation of the parts (and keeping track of what you've tried).


Although you did not document exactly how every piece came apart in the first place, you can document how it comes apart now, think carefully about which pieces might be assembled in a different way and then try that. It's never too late for some forethought!

Good luck!
12-31-2018, 01:04 PM - 1 Like   #3
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QuoteOriginally posted by photoptimist Quote
But first a question: you say the lens focuses at 1.5 meter at it's furtherest. Is the image nice and decently sharp across the frame or is it unexpectedly blurry in the center and/or corners?

If it is sharp, that indicates that all the elements are in their correct relative positions but something prevents the whole assembly from moving close enough to the sensor or film plane to achieve infinity focus. That suggests an issue with how the helicoid or the focus ring are assembled together and relative to each other. Some lens' helicoids have multiple starts so that rotating the inner or outer helicoid by 180 (for a 2-start helicoid), 120 (for a 3-start helicoid), etc. gets things in the right location.
I believe @photoptimist has identified the most likely problem here.

It's a while since I've serviced a 44M, but I'm pretty sure it has two or three possible positions in which the inner and outer focusing helicoids can mate, and only one of them will give the required focusing range.

The thing to do is disassemble to the point of unscrewing the helicoids. Do this last part slowly, with a gentle "pulling apart" so that you know when the inner and outer sections have released. When they have, stop unscrewing them, push the two together gently and then keep rotating in the same direction. You should feel a gentle click from the threads when the next possible position is reached (this will be very subtle, but you should be able to feel it), at which point reverse the direction of rotation to screw the helicoids back together again. Re-assemble, test, and if it's still not working, try the same approach again.

Does that make sense?
12-31-2018, 05:38 PM   #4
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Yes, I think it does. I'll try that. Thanks for the responses from both you and photoptimist.



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