The Mir-20M lens is not very well-known but certainly a great addition to anyone's camera bag. Manufactured in late 20th century in Russia, it comes in multicoated and non-multicoated varieties. Although normally, multicoated optics are worth seeking out, my own copy is not multicoated and still produces wonderful results.

The Mir-20M is a 20mm, 1:3.5 lens. It seems to be available only in the M42 mount. Thankfully, there are adapters to put M42 lenses on most modern digital cameras. In the case of Canon and Pentax, the adapters are just rings that contain no optical elements; for Nikon, an optical element is needed to maintain the ability to focus to infinity.

Mounted on a camera, this one certainly looks unusual.

It is fairly heavy and getting to the aperture ring when it is mounted on a camera takes some getting used to. Another trick when using this one is avoiding flare when shoting in the general direction of the sun - the easiest way is to hold the left hand between the sun and the lens since there are no hoods available.

However, the Mir-20M rewards the photographer with excellent image quality. I am especially fond of its colour reproduction, the images almost look like I was using a polarizing filter. A couple are posted below - the sky simply does not get that blue in Vancouver in March. Come to think of it, it does not get this intense blue around here at all. There is some distortion around the corners, but it is only really visible in indoor pictures, where there are vertical elements near the corners of the shot (walls, doors, etc). As you can see in the outdoor images below, the distortion is not obvious at all.

In conclusion, Mir-20M is a very unusual lens which is certainly worth owning, both for the brilliant image quality and the looks you get from people when taking it for a walk on a nice day.

Note: there are reports on the Internet that using the supplied filters on the lens may interfere with the mirror on Pentax dSLR bodies. I have not tried using those filters and cannot confirm and deny them. However, looking at the lens itself, I would not be surprised if they were true.