[dvhowells]

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Yes, yes, crazy, I know. I know I'll see the image circle. But it's more for fun than photo quality.

The Auto 110 was my first camera 35 years ago. My dad bought it while on deployment in Japan and when he upgraded to the Minolta X-700, I got the 110 as a birthday present when I turned 13. That camera is long gone, but I recently purchased one with 4 lenses and I'd get a kick out of using the lenses on my 5D Mark IV. No direct 110 to EF adapters, unsurprisingly. I can adapt to Q-mount, Sony's E-mount and micro 4/3. So I considered trying to stack adapters and go from Q, E or 4/3 to my EF, but the adapters don't seem to go that direction. No one wants to mount 4/3 glass on a full frame I suppose.

Any ideas? Or does anyone have some solid CAD skills and a CNC machine handy?

[steephill]

Long story short - it won't work. The big problem is registration distance - the distance from the lens mount to the sensor/film. If the registration distance of the third party lens is greater than that of the camera body then you might be able to use a simple mechanical adaptor. If it is the other way around then you would need a corrective lens built into the adaptor to allow infinity focus. 110 lenses have a much shorter registration distance than the Canon so would need extra glass which turns the adaptor into a teleconverter.

[dvhowells]

Learned something new. Did know that was called registration distance, but I wondered if that would be an issue with stacking adapters.

So this is possible, but it would have to be a custom job which I am not equipped for. Fun to contemplate though. Thanks Steephill.

[pepperberry farm]

if I remember correctly, 110 lenses do not have an aperture in them, which creates a new series of challenges...

[reh321]

Learned something new. Did know that was called registration distance, but I wondered if that would be an issue with stacking adapters.

So this is possible, but it would have to be a custom job which I am not equipped for. Fun to contemplate though. Thanks Steephill.

The problem is, registration distance of the 110 was less than the registration distance of any DSLR, so your overall adapter would need lens(es) to provide an effective registration distance less than what your DSLR provides. Providing that effective reduction in registration distance without ruining Image Quality would be a job for a well-paid professional in optics.

[Marcus Rowland]

It ought to be possible to adapt it to Micro 4/3 if you can put in some spacers, but I think EF mount is very unlkely to work.,

Micro 4/3 flange focal distance (another name for registration distance) 19.25mm
Pentax 110 flange focal distance 27mm

Flange focal distance - Wikipedia

and I found this on eBay UK

UK Lens Adapter For Pentax 110 PTX110 Lens To Camera Micro Four Thirds 4/3 M4/3 632088772205 | eBay

[barondla]

Pick up a Pentax Q body and a cheap adapter. The Q is Pentax's digital 110.
Thanks,
barondla

[Marcus Rowland]

By a weird coincidence I just bought a job lot of lenses that will apparently include a Pentax 110 50mm. If I'm reading things correctly the flange focal distance is very slightly less than Leica M39, which means that if I cut a hole in a Micro 4/3 body cap and secure it there it ought to be at about the right distance to focus to infinity - if the lens gives good results I'll be looking at getting a proper adapter, but they seem to be fairly expensive for what they are, I want to test it first.

In the past I've experimented with a weird 50mm lens that used stop discs for aperture, and I think it ought to be pretty easy to put a stop sized for say F8 behind the lens. Does the commercial adapter do anything like this, or is it simply f2.8 all the time?

[reh321]

By a weird coincidence I just bought a job lot of lenses that will apparently include a Pentax 110 50mm. If I'm reading things correctly the flange focal distance is very slightly less than Leica M39, which means that if I cut a hole in a Micro 4/3 body cap and secure it there it ought to be at about the right distance to focus to infinity - if the lens gives good results I'll be looking at getting a proper adapter, but they seem to be fairly expensive for what they are, I want to test it first.

Have you done any testing yet? You didn't specify camera, {MFT?}, butI would think a 110 lens would have a much smaller image circle than even a "APS-C" sensor, although it might fit a MFT sensor.

[Marcus Rowland]

Sorry, yes, it's MFT. The lens has arrived but I'm still waiting for a cheap body cap I ordered after I won the lot, since I don't want to cut up the one that came with my camera. I'll post again when I've tried it.

[surfar]

Have you done any testing yet? You didn't specify camera, {MFT?}, butI would think a 110 lens would have a much smaller image circle than even a "APS-C" sensor, although it might fit a MFT sensor.

M43 is same size,but the lenses will cover apsc too

[Marcus Rowland]

Tried it today but it definitely needs a stop behind it! I only got a couple of photos since I had to head out somewhere, I'll take it out for a proper test as soon as possible, and post when I have more:





Full-sized images are here:

https://www.flickr.com/photos/150868539@N02/49329664162/in/album-72157712515953133/

Later - the little stops I used for the other lens (an Itorex "teeny lens in T-mount" abomination that is 50mm f40 - yes, forty - unless you make alternative stops) are way too small to mount easily inside the body cap I'm using. I've just ordered a sheet of black plastic card, I'll make some stop disks out of that. I think they can just be held in place with a modified paper clip. So there will be a delay while I get the card and make them.

[Marcus Rowland]

Quick update on this - the stops really didn't help. I think that they need to be fairly near the sensor (at the same distance as the aperture was in the actual Pentax 110 camera) to work, and I really don't want to mess around with that, too much risk of damaging the sensor.

I did also try this with a 24mm lens, image quality was about the same: