This is a lens I got from Per-Olof back in 1992 - when he by accident smashed a very large, special plate i just had bought.
I suggested him, that instead of money or replacement - he could give me the "Russentonne" [The Russian barrel] lens, which he had but never used. The value was something like 300 SEK, which is equivalent to something like 160 € today. (it can still be had via eBay for relatively cheap sums between 80 to 200 € - often from Ukraine). It often goes under the shortened name "MTO" 3M-6A. Anyway, these are relatively pretty good lenses if you compare them to most cheap Chinese mirror telephoto lenses. All the latter which simply suck.
Yet, you need to do stable photography (tripod), very careful focus - and additionally digital voodoo, in order to make the images shine. The native contrast is on the low side, so are the colors. And i often get a strong greenish look.
Digitally this can all be addressed, of course. Then the lens is actually interesting. It isn't every day I can do 1000mm with an Olympus camera. I had the Russian lens somewhere among old lenses in a drawer, deep buried in a closet.
There are two other versions
One is called MTO 500mm ƒ8 - which is slightly less bright. I don't know anything about the preformance.
There is also a true Maksutov MC MTO-11CA 1000mm f10 (fullframe) version. (It would result into 2000 mm on my Olympus OM-1 camera). Even here, I don't know anything about the performance.
History of the MTO 3M-6A 500mm ƒ 6.3 lens
MTO is the brand name given to the family of mirror lenses developed by Dmitry Dmitrievich Maksutov [>Wikipedia] and produced in the Krasnogorsk Mechanical Plant and the Lytkarinsky Optical Glass Plant in Russia.The name "MTO" is an abbreviation for "Maksutov Tele-lens" or "Meniscus Tele-Lens."
At the World Exhibition in Brussels in 1958, a set of lenses, which included the MTO-500 (theƒ8 version ?), was awarded the Grand Prix, the highest honor.
In 1959 the lens was awarded the Diploma of II degree of the USSR VDNKh.
In my early 1990s
I never made really good images with this lens during times of analog film in the 1990s - because when I adapted it to my Canon T90 camera - the images got always unsharp due to heavy vibrations. The Canon T90 didn't have any mirror pre-release. Therefore the Maksutov 3M-6A 500 mm ƒ 6.3 mirrorless was practically unusable for me.
Night exceptions (1992)
Except during night when I was able to use longer exposures, putting my hand in front of the lens the first 2 seconds, and taking it away for several seconds, as the lens + camera had stabilized. It all felt quirky, though. I mean, to set the sharpenss was difficult. It is difficult at night, no matter what camera, even digital LCD's ones get noisy and slow - due to the slow aperture of ƒ6.3
It is extremly easy to be slightly off in focus, just a tiny notch - even if you think you are in focus.
Digital age (2002)
Later i tried a few times to use it with my first digital dSLR, the Canon EOS D30 - but back in the days, these cameras didn't have live view (and wouldn't have it for quite some time) - which made manual focus very, very difficult. Resulting in misfocused images more often than not.
When you have a lens which produces a focal length equivalent between 650 and 800 mm (on 1.6x as well 1.3x crop factor cameras) - even the very slightest difference in focus, means an unsharp image.
Which most of them where. Slightly out of focus. Especially when you zoomed in, it became painfully obvious.
(Aug 2002) • Canon EOS D30 with
Maksutov 3M-6A 500 mm ƒ 6.3 = 850 mm
Solar Eclipse, Turkey (2006)
Later I used this lens in Antalya, during the Total eclipse of the sun on 29 March 2006 and the Canon EOS 1D Mark II - still no live view, but with better results (especially when using a little bit of AI sharpening today).
(29 March 2006, Lara, Antalya) • Canon EOS 1D Mark II with
Maksutov 3M-6A 500 mm ƒ 6.3 = 650 mm
(29 March 2006, Lara, Antalya)
1000 mm focal length, tested Today
I wanted to give the Maksutov 3M-6A 500/6.3 lens a new chance to prove itself. And wondered, which would be the better camera to create the longest focal length. Well, the Olympus OM-1 micro four third camera. Here you have a factor 2x in focal length. Therefore it would result into a whopping 1000 mm ƒ 6.3 lens.
I bought a good M42 to M4/3 adapter - and used it today in all kinds of settings (on tripod !) Without IS, with IS, with 2s delay, and of course electronic shutter which is vibration free.
The images get better, once you make correction on Photoshop - especially in terms of contrast - because the originals are often a bit dull in both color as well contrast. Then i applied Topaz Sharpening AI - which gives the last touch to the finer details by chiseling them out.
Then it starts to shine.
(10 Oct 2025) 1000mm with Olympus OM-1
(10 Oct 2025) Globe Arena, 7 km from my balcony with 1000 mm
(10 Oct 2025) Tree in front of my balcony with 1000 mm
So, it is pretty useful with careful practice
I mean, i practically got it for free. And I never threw it away. Now it starts to shine in ways, it has never done before !!! After all the digital alterations I did - the performance is more in line with a Sigma SPORT 60-600 mm lens on a Canon EOS R6.
With the slight advantage, that on the OM-1, it results into a 1000mm focal length, that is the longest i can accomplish today.
Kind of cool !
It is kind of cool to use a 500 mm mirror lens, getting out a 1000 mm lens with the Olympus OM-1 which is now my longest lens in my lens arsenal when used on the OM-1 camera. The advantage is that the mirror lens is much much lighter, being a robust metal Russian/Ukrainian construction - way less bulky than a Sigma SPORT 60-600 mm lens.
I just wanted to test this. And while the original results are kind of dull and not critically sharp-sharp. Yet, after all digital voodoo, the images look very nice (optic technically, I mean).
Donut bokeh
Mirror lenses produce donut shaped bokeh !! You either hate or love it. It is a bit annyoing, but it depends on the motive and distance.
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