Maker: NIKFI / МКИП (Russian Film Institute)
Model: EP-4 (зп-4)
Measure type: Selenium
Measure type: reflecting/averaging and 2D incident (possibly 3D incident)
I got serious about exposure meters when I began researching the Norwood Directors (see The Many Lives of the Norwood Director), so when I saw this for sale, I jumped at it. The fact that it's Russian and hard-to-find was gravy.
I've found precious little about this. Russian stuff is notoriously difficult to research, between the vast differences in culture, language, and the fact that the USSR was effectively a closed society. Almost all of what I've been to learn about Soviet-bloc equipment comes from a single source, The Authentic Guide to Russian and Soviet Cameras by Jean Loup Princelle. Every website I've visited refers back to Princelle. The book is great for cameras, but he only has a little bit devoted to accessories and other equipment, like exposure meters. He mentions the common ones like the Leningrads and Sverdlovsks, but there's nothing about this. The only mention of this meter that I've found so far has been at Photohistory, which is in Russian.
This appears to be a Russian version of the Norwood Super Director, yet it anticipates it by a couple years, if you assume "1955" is the date of manufacture. It appears to me that the serial numbers are sequential and carry across model revisions, so the EP-3 is probably from 1952, the EP-4 is from 1953 to 1955, and so forth. Mine is Serial #2003 and says 1955, which fits.
If you haven't already read my Norwood article, here's the short version of things. In 1946, an unusual kind of exposure meter began manufacture, and it was called the Norwood Director. It would go through a number of functional and cosmetic changes over the years (you can still buy versions of them today), but they're still pretty much the same as they were when they came out in 1946. They offered three things that made them unique: one was a hemispherical dome for incident light reading; the second was that the photo-cell was mounted on a revolving neck so it could be swivelled so that the meter face could be held at a comfortable reading angle; and the third was a set of calibrated metal slides that fit over the photocell and limited the amount of light that hit it. That allowed the user to "set" the meter to a locked-in film-speed/shutter combination and just direct-read the meter dial for the ƒ/stop. That was a nice feature for motion-picture work; fitting since the people who developed it (Don Norwood and Karl Freund) were cinematographers.
In the late 50s, the Norwood Super Director came out, made and marketed by the japanese company Walz. The Super Director's major difference was that they got rid of the metal slides (which were easy to lose) and instead placed a variable aperture in front of the photocell. By using the calculator dial, you figured out where to set the photocell aperture (they called it a "heliovalve") and then you could direct-read the ƒ/stop scale. This Russian meter came out a few years before the Super Director, and does something very similar. Instead of having a valve, the placed a continously variable iris (like the aperture in a camera lens) in front of the photocell—simply a different way of doing the same thing.
The Super Director, like all the Norwoods before and since, used a press-on or bayonet-mount scheme for connecting the photocell covers. The Norwoods had three: an opaque hemisphere for incident work, an opaque disc for incident work (ideally for graphic arts or copying), and a perforated grid for reflecting light. Like all loose accessories, it's easy to lose them (I've bought several Norwoods and none of them had all three). This Russian meter introduced an interesting idea—they skipped the hemisphere and went with the flat disc and a glass lens; each was mounted on the end of an arm, and the arms were connect to a pivot, so they were both permanently attached to the meter. You just picked whether you wanted the reflected or incident cover and clicked it into place. (It's possible that it originally came with a hemisphere, but I've never seen one. Unfortunately it's an in-between size: too small for my original Norwood and Spectra, too large for my later Norwoods and Sekonics.
In practice it's not quite as attractive as you might think. There's a little slide on the side that unlocks the arms, and both arms flip open at the same time, and the little captive bits (a piece of opal glass on one side and a honeycomb lens and grid on the other) immediately fall out. Plus mine is worn and one of the arms doesn't like to click back into place, so putting it back together again each time has been a chore.
Unlike the Leningrads, which were for amateurs, this was a professional piece of hardware. It was designed by NIKFI, the Russian film institute. It appears to have been made by their manufacturing plant (МКИП), or at least that's how I interpret it. It was meant for cinematographers (much the same as the Norwoods/Spectras had been), since you can aim the photocell somewhere and turn the body to comfortably read the meter.
Since I don't have an instruction manual, I'm still figuring this out. The knob on the upper half controls the iris, so I believe you set that to the GOST rating of your film stock. The higher the number, the wider the iris is, and that would show up as a higher reading on the meter.
There's a bracket on the outermost ring of the calculator dial that I believe is where you set the expsoure index (again in GOST), but after that I'm lost. I believe you press the button on the left side to unlock the needle and take a reading. But then what? There's an arrow pointing at 6 o'clock near the bottom of the dial but I don't know what I'm looking at. I can't figure out how to plug the needle reading into the calculator. If I ever figure it out, I'll update it here.
Here is a cross-reference chart for film speeds (ASA / ISO / DIN / GOST / others) .