Would a helios 2/58 fit on my nikon d50 dslr?

Would a helios 2/58 fit on my nikon d50 dslr?

I think if you looked at the specification of the Helios lens, you will see that it has the old, old, M42 screw mount.

You need to look for lenses that are auto-focus F-Mount.

No, but there are versions of the 50mm f2 Helios that will (made for the Kiev 17/19/20 SLRs) they may not meter, though, and definitely won't autofocus.

Not without adapter

There are adapters that allow you to screw in older types of lenses. Like manual focus lenses as the Helios 2/58. Which is an M42 lens.

It will not have autofocus [it never had] and some functions like metering won't work. Some models DSLR might not even accept a "no lens" situation. Though with most you can find a setting to allow shooting a picture without a known lens on it.

In short using these old M42 lenses is allot more manual work and some things might not work. Maybe they do sell adapters for Nikon to M42 that do have some spoofed data [acts as if some other lens is on it] to trick the camera to work better.

None of the 58mm/68mm Helios f/2 lenses will fit. While there are M39/M42 adapters available for the screw mount lenses, the Nikon flange focal distance is too long, so you won't get infinity focus, with the K-mount and Start mount versions adapters don't exist.

There's the Helios-81H which is a 50mm f/2 lens similar in optic to the Helios-44 series, the 81H is a Nikon F-mount lens, however because your D50 requires a CPU to meter, you'll have to guess exposures.

If you want to play with odd lenses, get yourself a Canon, FourThirds, MicroFourThirds, or Sony NEX. Otherwise you're better off sticking with CPU lenses for Nikon.