Zenit C

The Zenit C was one of the first Russian SLR cameras, it has a basic set of shutter speeds and a lens mount based on the Leica L39 but extended to allow for a reflex housing.

The Mirror is not of an instant return type, when you wind on it is pulled down into place by a string, the viewfinder is rather average with no focusing aids. The camera itself is very small and compact and rather good looking, however it is not a very good camera, it has plenty of flaws, such as it’s small viewfinder, non-instant return mirror, and the lens mount which limits the lenses available.

The lenses available for the Zenit M39 mount are all Russian lenses, such as the Industar-50, Helios 44, Mir-1 and other lenses, these lenses are all of good quality and are generally made of a brushed aluminium finish which tarnishes rather quickly, but the glass is normally very good.  The shutter speeds are the standard for a Zenit, 1/25^th-1/500^th and B following the older scale rather than the international scale.

This is a good camera for a collector but not for most users, as it is just awkward in use.

Zenit 3m

The Zenit 3m is one of the first Zenit SLRs, it either came with an Industar-50 or Helios 44. Mine came with Industar-50 which is a tessar based lens, which is quite sharp, I also have the Helios 44 which is a very good lens.

The Zenit 3m is a fairly small camera, made in out of
metal. It's a very basic camera, for example it doesn't have an instant return mirror, instead it is lowered when you find the film on. It has a fairly small viewfinder with a plain matte screen. It has the

same shutter speeds as most Zenit SLRs (B,30,60,125,250,500) with flash sync at 1/30th.

In use it's unusual due to not being able to see through the viewfinder until the shutter is cocked, the shutter speeds should only be set after the shutter is cocked, and the Industar-50 lens is unusual to use.

Here is someone elses page on the Zenit 3m
http://thecameracollection.blogspot.co.uk/2013/01/zenit-3m.html