I think every passionate photographer in his life has tried to shoot with Helios... In fact, this is an interesting optics and should not be abandoned despite being vintage and irrelevant in 20XX. But you can't just put old lenses on modern cameras, you need an adapter. Let's go through the main adapters for old lenses.
Mount m42 and m39
A huge number of Soviet lenses work on these mounts. Therefore, it is worth keeping in stock adapter m42-Canon EOS... Moreover, it costs mere pennies.
This is what the lens looks like Industar 50-2 (50mm f3.5) with m42-EOS adapter:
This is how the adapter itself looks like:
Threaded bayonet Leica m39 differs in a slightly smaller diameter, so you can buy ring М42-М39 and make up for this difference.
For example, for a macro lens Industar I96U 3,5 / 50 H-22:
You can also purchase immediately adapter m39-Canon EF.
Less popular are Pentakon Six mount lenses such as Tair 33V 300mm f4.5.
The Canon adapter looks like this:
Recent acquisitions - lens Mamiya Sekor 80mm f2.8 (645)... These are vintage medium format optics. But it can also be adapted to modern cameras. Another thing is that we have very few such lenses on sale, and I have not seen adapters on our websites. But на AliExpress you can buy everything, and there is this adapter.
Moreover, adapters can be combined. I was able to fit the Mamiya Sekor 80mm f2.8 lens on the camera Fujifilm X-S10 using a combination of adapters Fringer EF-FX II and the aforementioned Mamiya645-EOS. Focusing, of course, only manual... It looks like this:
The same perversion can be arranged for the Industar I96U f3,5 / 50mm lens with m39 thread with m42 adapters and Fringer EF-FX II for Fujifilm X-mount:
Naturally, this is not an exhaustive list of adapters for vintage optics. If you are looking for something that was not in this review, it is for sure the Chinese have.
Since we're talking about adapters, here are links to reviews of autofocus adapters: