Work, as my hero Jason Scott says, tends to be fractal. While I was working on my Pentacon 50mm f/1.8 review, I realised that I could easily break out the section on using the lens with modern cameras into a whole separate page on using M42 lenses on modern cameras. I found that, too, was fractal, so if you ever find that I've made a chart on interoperability between every single thing on every camera system ever...well, you know how that came about.
But I resisted the temptation! So here it is, the big chart of using M42 lenses on modern camera systems. All of these systems will require that an adapter is used; what's being discussed here is how useful your camera will be after you've gotten one. Links in the first row and first column take you to the relevant subsections of this page.
|Lens mount||Optics required||Focus confirm||Metering||High-quality adapters||Crop factor||Notes|
All autofocus SLRs
|No||Needs chip||Yes||No||1x-1.6x||M and Av modes. Rear of some lenses may collide with mirror of the 5D.|
manual focus < 1987
|No||N/A||Usually||Yes||1x||Won't work on the T50.|
|Micro Four-Thirds||No||Not needed||Yes||No||2x||No focus-assist, but you won't need it with live-view magnification.|
All autofocus SLRs
|Yes||Yes||Sometimes||No||1x-1.5x||No metering with cheaper SLRs.|
|Sigma SA||☠ ☠ ☠ ☠ ☠ ☠ ☠ NOT RECOMMENDED ☠ ☠ ☠ ☠ ☠ ☠ ☠|
aka Minolta AF
|No||Needs chip||Yes||No||1x-1.5x||Needs a chip to get in-body stabilisation working.|
|Sony E-mount||No||Not needed||Yes||No||1.5x||May need to set camera to shoot without a lens.|
This means that any adapter will require corrective optics to be able to focus to infinity.
The flange-to-film-plane distance of the M42 lens mount is 45.5 millimeters. If it's longer than that for your camera system, then you're going to have a bad time, because that means you've effectively got a small extension tube, and you can't focus to infinity with an extension tube. On top of this, you might have to add on a millimeter or two for your adapter.
You can get adapters with corrective optics, but I don't like the idea for three reasons:
If you want to find out the furthest distance to which you will be able to focus using an adapter without corrective optics, then try this:
Try it with various focal lengths; you'll notice that telephotos are much more useful than wide and normal lenses.
This is important for autofocus SLRs, which do not have optical focusing aids like a split-image or a microprism ring, to get accurate focus quickly. This is especially so on small-sensored SLRs with tiny viewfinders, on which manual-focusing is much harder. This becomes irrelevant if your camera has live view with zoom.
Some cameras are dependent upon the presence of a chip on the lens to know that there is a lens attached; as far as the camera is concerned, an M42 lens fitted via an unchipped adapter is the same as having no lens at all. Some of these cameras will refuse to meter if they don't know they have a lens attached. If this is the case, you will be stuck in manual mode, and you will have to measure the exposure by other means (or guess it).
I use this as shorthand to refer to adapters that were made by the manufacturers of the camera bodies. In this case, Pentax made them for their K-mount, and Canon made them for their FD cameras. Canon and Pentax are serious companies who know how to make this sort of thing precisely and consistently. An adapter made in a one-man machine shop in China won't necessarily be produced this accurately.
These adapters are not necessarily available new anymore. I'm sure the Canon FD one isn't, anyway (!).
If your only option is to get one of the cheap, non-camera-manufacturer adapters and you absolutely must have dead-on infinity focus across the whole frame (such as for astrophotography), then you're going to need either some mechanical engineering skills or extraordinary luck.
There might be aftermarket ones out there which are made to the quality of Pentax's and Canon's adapters; these guys look promising, and expensive.
This is the size of the sensor relative to the size of the 35mm film for which M42 lenses were designed. A crop factor of 1x means that the sensor is the same size (full-frame cameras), 1.5x means that the sensor is 50% smaller if you measure the diagonal.
This has three effects, one obvious that you all know about, two less obvious:
An unimpressed cat, shot with a Helios 44M-4 58mm f/2.
If you have the option for it, shoot your camera in centre-weighted metering mode. Matrix (evaluative) meters will get very confused by the dark image coming from a stopped-down lens.
If the camera needs a chip for certain functions to work, it might be a bad idea. Cameras have been toasted this way and it will certainly void your warranty.
Fuji made a series of "M42" lenses designed for their "M42" cameras like the Fujica ST705, with an additional mechanical lug to give you open-aperture metering on those bodies. These will not mount on an M42 adapter, so don't try it. (The silliness goes both ways; using normal M42 lenses on these cameras requires that you hit both the depth-of-field preview button and half-press the shutter for metering.)
Beware of the 5D, and probably other full-frame cameras. The rear element of some M42 lenses will collide with your mirror when focused to infinity. See over here for more information.
Otherwise, you're OK here, except you'll need an adapter with a chip to get focus confirmation. Don't bother with these if you have live view; use that instead for better results. You used to be able to get focus screens with manual-focus aids, but Haoda doesn't seem to be around anymore and KatzEye Optics are no longer taking orders. Oh well.
Shoot this in Av (aperture priority) or M (manual) mode; the other modes won't work properly.
Because the EF-M mount has an shorter flange focal length than the EF mount, M42 lenses work great there, too. Check out this video shot with an EOS M and Pentacon 50mm f/1.8. It looks super to me!
The Canon FD mount went obsolete in 1987, but I threw it in with the modern lens mounts for fun. I love the A-1 that much!
As a general rule, if your camera can do stopped-down metering with Canon FL lenses, it'll probably be able to do stopped-down metering with M42 lenses via an adapter. I know that the T50 definitely won't work (unless the only shutter speed you ever use is 1/60). I know that the A-1 and T90 will work, and the F-1, T70 and AE-1 probably will as well.
Canon made an adapter for these, and adapters claiming to be genuine Canon ones are quite abundant.
You should be fine here. You probably won't get focus confirmation, but you don't need it with live view. Don't get caught out by the crop factor, though.
You may have to enable a setting in the menus to tell your camera to shoot whether or not it thinks it has a lens attached.
Takumar 135-600mm f/6.7 mounted on a Nikon D700. Photo by Eric Budworth, used here with his permission.
See "Optics required" above; the flange-to-focal-plane distance for Nikon is a millimeter greater than that of the M42 mount.
Other than that, you should get focus confirmation on all digital bodies and all AF film bodies, but you won't get metering on many of them. As a general rule, I gather that if your camera can meter with manual-focus lenses, it'll give you metering with an M42 lens mounted via an adapter. The single-digit and three-digit cameras (except the old D100) should all be fine, and so should the D7000.
I'm not sure it's worth bothering with on Nikon. On the other hand, see what this guy did with a D700, Pentacon 135mm f/2.8 and non-correcting adapter. It looks fantastic!
Full-frame shooters should be especially wary of adapters with corrective optics. Eric Budworth, a reader of my site, took one for the team and bought an adapter with corrective optics to use his monster Takumar 135-600mm on his full-frame Nikon D700. Surprise: the optics in the adapter he bought did not cover a full-frame sensor! Here's what it looks like shooting a blank subject:
Photo by Eric Budworth, used with his permission.
This was not disclosed when he bought it, and it was not a batch defect because the supplier of the adapter admitted it was a known limitation of their adapters. This isn't inherent to having an adapter with corrective optics; it's a fault with adapters made by firms who are not serious optical companies – and none of the companies that make these adapters are serious in the same way Nikon, Canon or Pentax are).
My readers are the best, though; nobody would know this without actually buying one, putting it on a camera and reporting back to me with the results and sample images. Thank you, Eric!
Pentax are real compatibility superheroes, as always. They care so much about lens compatibility that they've ensured you can use your Pentax digital SLRs with old Pentax lenses that went obsolete in 1975. Did you know that Pentax even sells an adapter so you can use lenses from their medium format cameras on your digital and 35mm SLRs? No sane person has ever used one, which means that Pentax even loves insane people, too. Thanks, Pentax! For contrast, some Nikon F-mount digital SLRs won't meter with manual-focus Nikon F-mount lenses that Nikon makes today.
Pentax made an M42-to-K-mount adapter until not so long ago. I don't think it's still being manufactured, but you definitely want to find one of these rather than the knock-offs; even if I didn't know that the genuine Pentax adapters are mechanically superior, I'd recommend you buy one just to thank Pentax for caring so much about you.
We love you too, Pentax! ♥ ♥ ♥
I've marked this as "not recommended" because there are reports of aperture stop-down pins on "auto" M42 lenses interfering with the mechanics of the camera. This is OK if you only intend to use lenses without aperture stop-down pins, but it could get very messy otherwise.
A solution to this is to use an adapter with a flange to push the stop-down pin so that it doesn't interfere with the mechanics. The problem with this, as far as I can tell, is that the location of the stop-down pin is not standardised in the M42 system. Thus, to ensure it works with all M42 lenses, you need quite a wide flange. But, that also means that some lenses with large rear elements will collide with this thick flange, and thus you will not be able to focus to infinity.
"Not recommended", despite the bold red capital letters and skull-and-crossbones symbols (Unicode is fantastic, isn't it?), is not the same thing as "certain death awaits thee". It means I think it's probable and I don't want anyone to be angry at me for saying something was OK when it was not. I don't own a Sigma camera, so anyone should feel free to correct me if they have tried it.
There's a whole FAQ about this over here. You will need an adapter with a chip to get SteadyShot in-camera image stabilisation, otherwise, as long as your body has an option to shoot without a lens attached you should be able to shoot in aperture-priority mode, if you have the latest firmware. Otherwise, M is supposed to work. I haven't tried any of this, but those guys have.
The tiny flange-to-focal-plane distance of the E-mount lenses works in your favour here. There's so much free space to play with that you can even get a tilting adapter!
You may need to go through your menus to change a setting that allows the camera to fire without a lens fitted. (Remember, the camera doesn't know it has a lens attached via an adapter.)
I don't know how focus confirmation works on these cameras, or if you have zoom on live view. I suspect on the latter count that you do.
The Helios 44-2 looks pretty funny on a Sony NEX.
A very serious cat, shot with a Helios 44M-4 58mm f/2.
Early M42 cameras had no ability to stop down the lens while shooting. You would open the aperture to focus, then manually stop down the lens to meter (if you had a TTL meter!) and shoot. These lenses are called "preset" lenses.
Later, manufacturers added mechanisms to cameras and lenses that would allow the camera to do the work of stopping down the lens. You'd still need to meter while stopped down (cameras had a button or lever on board to activate the meter and stop down the lens), but you could focus wide-open and the lens would be stopped down when you fired the shutter. These lenses are called "auto" lenses; that's about as much automation as you'll get in the M42 system.
For backwards compatibility with older cameras that did not support this "auto" feature, most lenses had an "M/A" switch that would allow you to operate them as preset lenses. The trick here is that your digital camera with the adapter is exactly like one of these ancient cameras because it doesn't have a mechanism to stop down the lens either.
(Side note: The Pentacon 29mm f/2.8 did not have an M/A switch; instead, it had a spring-loaded button on the side of the lens which would stop down the lens when pushed in. If you're shooting this on a camera which does not have a stop-down mechanism, then you either have to shoot it wide-open or hold down the button while shooting. This is a pain, and it also means you're prone to camera shake, making it nearly useless for tripod-duration exposures. A shame, because that lens really needs to be shot at f/8 or f/11 to be really sharp.)
So, if you're looking for lenses to use on your digital SLR, I'd recommend you do one of the following:
Andre, shot with a Pentacon 135mm f/2.8.
It's up to you whether it's worth doing this. For Nikon, I'd say it's not; they barely work on many camera bodies, and you won't get infinity focus on any of them. Besides, three of their cheapest plastic lenses (18-55mm, 50mm f/1.8D, 55-200mm VR) are optically so good that you don't need these weird ancient manual-focus lenses. But once again, always listen to the guy doing it and getting astounding results, not to the guy with the opinions who is not.
On the other hand, there's a lot to love about M42 equipment:
Let me know how you get on with them!
I can't own, test, or research every possible camera system, so your camera system might be missing. I'd like to know how M42 lenses work on other camera systems that I have not listed, and especially, I'd like to know how they work on professional video camera setups. If you've tried this, let me know.
Thanks to Jenn, Jenna, Trissy and Angelique for proof-reading this for me.