Continuing with USSR made SMENA 8M. I decided to take apart lens unit. It consist of upper cover with levers and lower unit with shutter blades, shutter spring-based mechanism and optics.

There are three blades. They are mounted on pins located on the rotating plate. Plate itself is moved by the shutter spring mechanism underneath.

In order to disassemble unit separating optics and shutter you just need to unscrew it hard. Most probably it will mangle focus limit pin, but I do not care about it that much.

Inside you can find a lot of grease which is good. It helps focusing ring to operate smoothly. Later I found that there is even simpler way to access optics. But it is good to know how everything works still.

In order just to access optics you need to unscrew 3 little pin-like screws on the aluminum optics unit cover. Optics, which consist only 3 elements is this little barrel in the middle on the picture below. The thing on the left is an inner plastic ring to set aperture. It presses down and lock aperture setting on the inner gap in the optics barrel.

As simple as it can be. Unscrew 3 scres and you are good to go with the optics barrel. Free of taking care of shutter spring mechanism.

About the optics itself. It has some pretty short registration distance so it could be mounted on mirrorless cameras. In order to mount it on DSLR you should use that cameras with short flange distance or use some teleconverter. I will try both later on.

Tried to manually put it on my M42 Praktica and I need to put it literally inside camera unit, just next to the mirror. Be careful then with your camera as you may damage mirror putting anything next to it.