Replacing a MEYER-OPTIX Helicord

I have a MEYER-OPTIK projection lens DIAPLAN 3.5/80, but it is missing its Helicord.

Whats the best way to fit it to a Fuji camera so I can still focus it? Is there one i can buy, or someone with 3d Printing plans?

Most projection lenses don't have a traditional helicoid, it's part of the optics holder, it's really more of an adjustment.

The OP in this thread does a lot of custom work, he permanently mounted my Meopta 70/1.4 to a V-NEX http://forum.mflenses.com/the-vnex-enlarger-lens-project-v2-0-t67487.html

At the very least, you'll get ideas, depending on how fast your lens is(it's size) and how close to the sensor it needs to be for infinity, the helicoid from a fast 85 SLR lens that has bad optics might be a good donor.

search eBay for helicoid Fuji x, you will probably find one with M52 threads, if the optics fit inside, that may do it for you. Here's an M42 helicoid https://www.ebay.ca/itm/M42-FX-Pixc...ns-for-Fuji-film-X-mount-adapter/123067946640

there are also M52 to M42 helicoids of different lengths, you would need one that is short enough to reach infinity after it's mounted, plus a shallow M42 to Fuji X adapter.

how much effort you want to go through to do this will depend on how good the optics are, try some free lensing to find out if you like it.

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ignore the left lens (MOG Diaplan 100/2.8) but look at the macro helicoid (in this case suitable for Micro 4/3). Once you glue a M42 ring (or a M42 macro extension tube) to the back of a lens you can simply use a generic helicoid designed for your camera (search for macro helicoid https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=macro+helicoid&_sacat=0 )

Why am I not surprised you've already done this to this lens

Is infinity close to the fully retracted length? Can you adjust infinity before gluing?

Lightshow said:

Why am I not surprised you've already done this to this lens

Is infinity close to the fully retracted length? Can you adjust infinity before gluing?

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Every lens I refit is fine tuned to achieve infinity at the helicoid fully retracted so it feels like using a lens with in-built helicoid (SLR lens for example). The fine tuning is done with adding spacers or rings and if not "just right" I often shave the mating surface of the ring to be glued on the back of the lens. I use JB-Weld modified epoxy but other brands work fine too of course.

Some Russian film projector lenses however require a shorter helicoid and fitting a M42 ring on the back is very challenging (not much room to play with)


refitted Russian projector lens RO501-1 onto Olympus E-M1

Any lens that I find outstanding is then pretty much permanently mated to a helicoid so I don't have to futz with screwing and adding rings to get it right again each time I use a helicoid with a different lens. For the cost of a helicoid (about $26) is for me an encouragement to then grab that lens and just go out and shoot instead of leaving it behind because "it's too much hassle" to refit it

Thanks for your responses. I have purchased a suitable helacoid and we'll see how we get on once it arrives