Quantaray 500mm f8 Mirror Lens - Another Look

The reason I like going to used camera shows is that sometimes, I can pick up some cheap lenses to try. In most cases, they are cheap for a good reason, but once in a while there could be gems hidden among the rocks.

Not really sure what's happening lately but I have picked up a few mirror lenses from the last few camera shows. I normally would ignore mirror lenses, as they are (were?) not my thing. The Minolta Rokkor-X 250mm f5.6 mirror lens has changed my attitude somewhat about the usability/usefulness of these lenses. Still, I am supremely cheap and I would not pay more than $50 for one of these lenses. The only exception is the Minolta 250mm, because it's so small, but it was still under $100. So far, I have three other mirror lenses aside from the Minolta, which costs from $10 to $40: Soligor 500mm f8.8 (haven't tested it on the A7, but I think it's a piece of junk), Makinon 300mm f5.6 (very good), and the Quantaray 500mm f8 (not bad).

The Quantaray has a T-Mount, like a lot of third party mirror lenses. Fortunately I have lots of T-Mount adapters and I used the T-Mount to M42, which in turn, mounts on the Yeenon helicoid to give me even closer focus capability. The lens is very well made like the Makinon 300mm f5.6 and it feels solid and focuses smoothly.

I tried the Quantaray 500mm f8 on the NEX-6 before. It's usable, but definitely too long at the equivalent of 750mm. The small angle of view makes focusing extremely hard to do. For those pictures that turned out, focus wise, the quality isn't bad at all. On the A7, which I have been using with the Quantaray, focusing is much easier, but that's relative; mirror lenses have very short focus throw and due to the focal length, a small adjustment/movement means the focus is off by quite a bit. Lens like this are meant to be used on tripod, or least on monopod, but I am not really a tripod kind of person, unless it's absolutely necessary, so all the shots were done handheld. I am quite surprised I get many more keepers than when using it on the NEX-6.

Do I like the Quantaray 500mm f8? I would say yes on full frame, only because it's relatively cheap and you get a lot of reach for that kind of money.

Man and his best friends - Sony A7 & Quantaray 500mm f8. Click for larger.

Steel rods - Sony A7 & Quantaray 500mm f8. Click for larger.

The Welder - Sony A7 & Quantaray 500mm f8. Click for larger.

Bike Posts - Sony A7 & Quantaray 500mm f8.

Revival of Mirror Lenses?

There seems to be a trend that mirror lenses are becoming more popular. In fact, there are new mirror lenses being made (Tokina and Samyang 300mm f6.3). I think the main reason for this surging popularity is due to the high ISO capability of today's digital cameras. Back in the old, film days, mirror lenses were designed as a compromise. You trade larger maximum aperture of glass lenses for lighter, smaller, but very small maximum aperture, typically f5.6 to f11, except the Russian Rubina 300mm mirror lens is very fast at f4.5.

Mirror lenses are much cheaper to make and most optical manufacturer made at least one design. Canon, Nikon, Pentax, Minolta, Zeiss, and of course the Russians. But the most popular (cheaper) ones were made by third party lens makers, like Sigma, Vivitar, Tamron, and a plethora of rebadged brands like Makinon, Quantaray, and many others. Typical focal length ranges from 250mm Minolta RF Rokkor-X to the monstrous 5200mm made by Canon.

There are severe limitations to the mirror lens design. Other than the already mentioned small maximum aperture, the other is that the aperture is fixed. Furthermore, image quality is not comparable to the traditional glass lenses and for this reason, many people viewed mirror lenses are a cheap alternative to the real thing and wouldn't even consider using one, however cheap they were. Lastly, all but one mirror lens can auto focus, and that's the Minolta (Sony) AF 500mm f8.

One of the reasons people turned away from mirror lenses is the very dark viewfinder they see when the mirror lens is attached to the camera. Remember that all film cameras had optical viewfinders; the smaller the maximum aperture the darker the viewfinder becomes. If you ever tried a 500mm f8 mirror lens on a camera with optical viewfinder, you will see why; it's next to impossible to focus with such a dark viewfinder. Split screens do not work if the aperture is f5.6 or smaller. But dark viewfinder is just one of the inconveniences. The other, more severe shortcoming is the slow shutter speed caused by the small aperture and the need for faster shutter speed to counteract the shake due to long focal length. Most people shot ISO 100 to 200 film, and 400 is pushing it unless you are shooting black and white. So, that 500mm f8 mirror lens is pretty much limited to sunny days and mostly tripod bound, or you will get blurry pictures caused by mis-focus and/or too slow a shutter speed. As an example, for a 500mm f8 lens, you would need about 1/500s on full frame to ensure the picture is reasonably sharp, but on a cloudy or overcast day, you would have to crank up the ISO to 3200 in most some situations to attain the 1/500s shutter speed. For film, ISO 1600 is already hard to find and expensive, and the grain is the size of a golf ball. If you have never seen what picture looks like with the ISO 1600 film, you are just spoiled by the modern CMOS image sensor's high ISO capabilities :)

There are some very fine mirror lenses and three of them come to mind: Minolta AF 500mm f8, the Carl Zeiss Mirortar 500mm f8, and the Russian Rubinar 300mm f4.5, possibly the brightest mirror lens made for 35mm format. All of these lenses are very pricy or difficult to find. Fortunately, there are some gems amount the third party mirror lenses. I briefly looked at the Makinon 300mm f5.6, which is actually quite a nice lens. I am sure there are many more out there.  My advice is not to let the name on the lens sway you. Try it for yourself. Often the noname lens was made by the same manufacturer as a more expensive lens with a different name.

Lamp Post - Sony A7 & Quantaray 500mm f8 Mirror Lens.

Quantaray 500mm f8 Mirror Lens Sample Pictures

One lens I bought from the camera show this past Sunday, but failed to mention, was the Quantaray 500mm f8 mirror lens. This is a very cheap lens and when I bought it, I already expected it to be a dud. Besides, I don't even like mirror lenses, especially the ones with f8 aperture. But the price was too good to resist, and it came in M42 mount, so I caved it.

The lens is actually well made, and focuses very smoothly. As it turned out, I was surprised that it's quite decent. Maybe not as good as the Minolta Rokkor 250mm f5.6, but it certainly is not a dud. In terms of sharpness, it's passable for a mirror lens, if you can focus it properly. You may notice that all the pictures below are kinda grainy, that's because I had to set the shutter speed to around 1/1000s to maintain safe shutter speed. At that kind of shutter speed, even in broad daylight, the ISO is around 1600. This is one reason I don't like mirror lenses. The 500mm focal length (750mm equivalent on NEX-6) is way too long for most purposes. Holding it to my eyes, I feel like suffering from ET; the view jitters so badly that focusing becomes a problem.  Seriously, I don't know what good a lens like this is for. It's too slow for action shots/birds, too long for most uses, and putting it on a tripod is almost mandatory. The only positive I see is the very light weight for the focal length.

I shot quite a few pictures, but the keeper rate is rather low, due to blur. I am sure if used on tripod, it will perform much better, but I am not a tripod guy. Maybe a camera body, like the E-M1 or E-M5, with in-body-stabilization, will make it easier to use.

All pictures below were shot using a NEX-6 & Quantaray 500mm f8 mirror lens. Except for the third picture, all were taken through very thick glass from 17th floor.