In MotoGP, the world’s highest level of professional motorcycle racing, the bikes that riders ride are called liter bikes because their motors have an engine displacement of 1,000 cubic centimeters (cc). Since cubic centimeters are equivalent to milliliters and 1,000 milliliters equals one liter, the liter bike moniker becomes an obvious one. These motorcycles are among the fastest production road-going machines in the world (BMW’s latest 1000RR has a top speed of 188 miles per hour and travels from zero to sixty in just 2.6 seconds). They are top of the heap.
I recently picked up a monster of a lens, a 1,000mm F/10 Rubinar mirror lens, and my mind immediately made the leap. This meter lens (a term I’ve just invented and should probably trademark), boasts an incredibly long focal length, one that very few photo geeks will ever own (or care to own). It’s a highly specialized lens, like the liter bikes I mentioned, and in the same way that those high-speed machines are mostly overpowered for everyday riding, so too is the Rubinar 1000mm lens a bit ridiculous in everyday shooting.
The Rubinar 1000mm lens is, according to random internet posts, a lens designed and built for use by the former Soviet Union’s KGB (secret police). Whether this is truth or just the fanciful musings of a bored Tom Clancy fan writing things on the internet, who can say? And does it matter if the lens was made for the KGB? Not really. It’s a 1000mm lens made in Russia. Let’s just leave it at that. What’s more interesting than any romanticized callbacks to the Cold War is the lens’ construction and optical formula, and what that means.
The Rubinar 1000mm is a catadioptric lens. Catadioptric lenses, also known as reflex lenses or mirror lenses, use a form of the Cassegrain reflector design, a type of optical assembly that uses a primary concave mirror and a secondary convex mirror to multiply the focal length many times. This design also has the important benefit of reducing the physical length of the optical assembly. Think of it as bang for your buck. You get a super telephoto lens (250mm, 500mm, or 1000mm typically) in a relatively small package. But there are drawbacks. Quite a few, actually.
To start, the centrally-mounted mirror assembly precludes inclusion of an adjustable diaphragm. The lens’ aperture is therefore fixed (in the case of the Rubinar at F/10). Adjustments to light pouring in through the lens must be handled via neutral density filters, usually installed at the back element of the mirror lens. This means that anytime we want to adjust light without changing shutter speed we need to remove our lens.
The fixed f-stop combined with the super long focal length also means that mirror lenses typically have incredibly shallow depth-of-field (more pronounced at closer focus distances). This can make contextual photographs of any subject closer than the horizon a challenge.
Lastly, due to the iris-shaped mirror assembly, out-of-focus elements of a frame can take on a similarly iris-shaped bokeh. People typically call this “donut-bokeh.” Some shooters like the look, some don’t, but it’s distracting in any photo in which the intended subject is anything but the bokeh.
Over the last five decades, lots of companies have made mirror lenses. I’ve used ones that sport names like Minolta, Nikon, and Sony, and while they’ve been interesting and fun diversions, mirror lenses have never been something I feel a serious need to own. Even in the specialized instances in which these lenses should’ve rightly earned their lunch, they mostly didn’t. Contrast was always too low for my taste, and I don’t do a lot of birding or spying. I wondered if the Rubinar would be any different.
Images were consistent with what I expected. Low in contrast, a bit hazy, paper-thin depth-of-field. It’s true that the lens has a massively long focal length, and this is of course its greatest selling point. The field of view of a 1000mm is really something to behold, if you’ve never experienced it. And when, in my madness, I coupled the lens to a two-times teleconverter (effectively creating a 2000mm focal length lens) I was fairly blown away by how far I could see.
There was one particular astounding moment in which I was at the local bay gathering sample shots. I’d brought with me a standard 50mm lens and, of course, the Rubinar 1000mm. I sat there in the early morning sunshine looking for a subject. The omnipresent seagulls were swooping for their lunch, crabs stranded by the receding tide. Great subject, unfortunately, the Rubinar is far too slow to shoot birds in flight (at least in my shaky hands). The field of view is just too narrow. Instead, I focused on a different set of creatures who were also forging for their meal – a pair of slow-moving humans digging for clams. That these subjects filled the entire frame was pretty remarkable, considering their size when shot with the 50mm lens.
But more incredible was the fact that, off in the distance, I was able to spot some towers that were simply invisible to the naked eye. Though hazy and low in contrast, for sure, the lens made it possible to see things that I otherwise couldn’t see. That’s pretty good. But this thrill wore off pretty quickly.
Later in the evening, with the specter of this lens review looming over me, I knew I had to get the Moon shot. What kind of super-long telephoto lens writeup would this be without a beautiful photo of the Moon?
As the sun was setting, I set up my tripod, mounted the camera and lens via the lens’ handy, rotating tripod mount, and set to work framing the shot. And there it was, the Moon, big and bright on the camera’s LCD screen. But there’s a reason I’m describing this photo in words, rather than simply posting it. It never happened.
As I slowly dialed in focus to shoot the Moon as sharp as possible (which, with the Rubinar, isn’t all that sharp), I heard a metallic ping! resonate from the innards of the lens. I paused with worry. And even though any ping makes me happily recall the ping-loving Captain Ramius (more Tom Clancy references, really?) I knew the sound wasn’t good.
I moved on, ignoring my worry, and went back to work. I rotated the focus ring again and again, back and forth, confused as to why the image wasn’t resolving. And no matter how many adjustments I made, the image refused to focus. I’m a pretty bad photographer, but not this bad. Something was wrong, so it was back to the studio with the lens in hand for some testing. Sure enough, something internal had broken. In addition, the lens focus was not corresponding to the focus scale on the exterior of the lens.
I attempted a repair and found that a brass tab inside the lens had simply fallen apart. This tab acted, as far as I can tell, as a stop at the extreme end of the lens’ focus range. I screwed the lens back together in an approximation of its correct position and determined that focus was still possible, if inaccurate according to the lens’ painted focus scale. Still usable, but imperfect.
Back to the outside I went. I mounted the lens and camera onto the tripod, framed the Moon, focused and prepared to shoot. Just before I fired the shutter the camera’s live-view LCD went dark. But not the dark of a drained battery or an automatic power-save shutdown. It went… sort of dark. Two minutes of “What the hell is happening?” led to another sad realization. One of the two reflex mirrors had simply fallen out and was lying on its side within the lens barrel.
There could be more sample images in this article, but I know when I’m beaten. And slogging through editing twenty sample shots from a lens that I can’t possibly speak highly of is not a good use of time. I packed up my gear, and promptly tossed the Rubinar 1000mm onto the graveyard of broken gear that makes up too-many-square-feet of my basement.
The Rubinar’s M42 universal screw mount makes it one of the more versatile vintage mirror lenses available today. It can mount to any USM film camera, naturally, including the most popular examples from Pentax. It can also be easily mounted to a mirrorless digital camera via an inexpensive adapter. I mostly shot mine on the Sony a7II. That said, versatility isn’t everything, and if you’re buying a mirror-lens to adapt to mirrorless cameras, there are better choices.
If you need a vintage mirror lens, go for one of the Minoltas or the Nikkors. If you want the best value, look for a newer lens. There are some really decent and incredibly inexpensive mirror lenses being produced by third-party lens makers, and their performance will likely match or best the Rubinar. Grab a 500mm mirror lens for $85 and pair it with a teleconverter.
I know that it’s a bit unfair to discredit a lens based on the mechanical failing of one example (they made a lot of these lenses, after all, and not every one of them has failed) but the fact is, it failed. And even had it not failed, based on image quality from the shots I did manage, and because of the lens’ relatively high price, I can’t in good conscience recommend the Rubinar 1000mm to anyone but the most stalwart Soviet loyalists. To paraphrase the good captain again, we must give this lens a wide berth.