What is mount of this lens? Zenit-E may be?

[mdmosta319]

What is the name of this Mount? -M42??
What converter should I use to use this on Nikon?

 

[pendennis]

Yes, the Zenit-E uses the M42 mount. Probably a M-to-Nikon adapter.

 

[petrochemist]

You won't be able to get infinity focus with that lens adapted to Nikon unless the adapter has an optical element (effectively a short teleconverter typically ~1.2x).
With an adapter (without optics) the lens will sit at least 2-3mm further from the sensor than the lens is designed for. I expect this will give a maximum focus distance of something around a meter.
If cleaned up the lens should be capable of giving reasonable results, optical elements in cheap adapters will certainly degrade the results.

 

[mdmosta319]

You won't be able to get infinity focus with that lens adapted to Nikon unless the adapter has an optical element (effectively a short teleconverter typically ~1.2x).
With an adapter (without optics) the lens will sit at least 2-3mm further from the sensor than the lens is designed for. I expect this will give a maximum focus distance of something around a meter.
If cleaned up the lens should be capable of giving reasonable results, optical elements in cheap adapters will certainly degrade the results.

You won't be able to get infinity focus with that lens adapted to Nikon unless the adapter has an optical element (effectively a short teleconverter typically ~1.2x).
With an adapter (without optics) the lens will sit at least 2-3mm further from the sensor than the lens is designed for. I expect this will give a maximum focus distance of something around a meter.
If cleaned up the lens should be capable of giving reasonable results, optical elements in cheap adapters will certainly degrade the results.

Adapter without optics-
I won't be able to focus anything after 1 meter?
Would I be able shoot portrait photo?
N.B. I am newbie.

 

[petrochemist]

You won't be able to get infinity focus with that lens adapted to Nikon unless the adapter has an optical element (effectively a short teleconverter typically ~1.2x).
With an adapter (without optics) the lens will sit at least 2-3mm further from the sensor than the lens is designed for. I expect this will give a maximum focus distance of something around a meter.
If cleaned up the lens should be capable of giving reasonable results, optical elements in cheap adapters will certainly degrade the results.

Adapter without optics-
I won't be able to focus anything after 1 meter?
Would I be able shoot portrait photo?
N.B. I am newbie.

Without optics in the adapter it is working as a short extension tube (as used for macro to allow closer focusing).
The effect of the added distance between the lens & sensor is to make it focus closer, how much closer is dependent on the lenses focal length - more effect on shorter focal length lenses.
There are many long telephoto lenses that allow focus travel beyond the infinity mark - it may be some of these would still focus to infinity using the extra available movement & the lessened effect of the extension.

I wouldn't expect portraits to be practical with a 50mm lens mounted this way. It might be a 135mm will work OK but you'd have to try it to be sure.

Fortunately for me my cameras do not have this issue my SLRs/DSLRs have the same registration as M42, and my mirrorless cameras all have considerably shorter registration allowing plenty of room for an adapter.