About the Recumbent Reviews
Welcome to the the third in the series of Recumbent Reviews!
This series of articles will examine photographic equipment and accessories from an ordinary user’s point of view. You’ll find none of that snooty “I’m an expert so my opinion is the final word” guff you get from the professional reviewers you’ll find elsewhere on the interwebs. Here we’ll break new ground by throwing out a lot of opinion seasoned with speculation with a side order of silliness and whimsy. Ranting and raving are all part of the local colour!
Hopefully you’ll enjoy yourself while learning all about stuff that will help you take better pictures while draining your bank account.
The Reflex-Nikkor C 500mm f/8 is another one of those oddball lenses that I’ve bought. What puts this lens in the strange category is the fact that it is a stubbly, manual focus, ultra-high magnification telephoto that is really light. It’s all done with mirrors!
Nikon stopped making mirror lenses in 2005 so you’re not likely to be able to find one new, at least not from your local camera store. I got mine used off of eBay.
Way back in the day when I had long flowing hair all over my head that was even more abundant and nicer than Fabio’s ever was, I was becoming increasingly interested in photography.
I got my start years before by worshipping my dad’s SLR, a Minolta SR-1, and the wonderful images he captured. Then I ordered a tiny camera from the back of a comic book, and then I got hold of a couple of Instamatics and a fully manual 16mm still camera. Then while in high school in the ’70s, I got to the point where I wanted something a little more capable — an SLR.
A couple of guys at school whose photos and photographic knowledge I admired all had Nikons, so when I got my first summer job I ran down to the camera store and bought an Olympus OM-1. I’ve always been The Quiet Rebel.
I bought the OM-1 for a couple of reasons… it was touted as being great in low-light situations and I was interested in taking photos at night and of bands performing either indoors or outdoors after dark with only the stage lighting as a light source. The Olympus lenses were said to be excellent, and the OM-1 was considerably less expensive than Nikon’s cameras were.
I was anxious to pick up a “real” camera but I was also a realist. That first job was at one of Montreal’s amusement parks, Belmont Park, which was really far away from where I lived so before I bought a camera, I ran out and bought a moped as soon as I possibly could.
Travelling by moped cut an entire hour off my commute time each way and it would prove a lot of fun during my free time! Once my transportation was taken care of and as soon as I squirreled away enough cash I ran down to the camera shop and bought the Olympus. As it turned out, there was a bus strike that summer so a lot of Belmont Park’s employees couldn’t make it to work but since I had reliable transportation, I was working fifteen or sixteen hours per day, six days a week so dough was rolling in and I could afford to buy additional lenses and a nice flash unit.
As is the case with most any teenager, I heard about a lot of different things going on around the city and had the freedom to check a lot of them out. There were many opportunities for great shots.
The ’70s was a great time for photography, with the advances in electronics and materials sciences permitting better films, more features on the cameras, and better lenses. The Reflex-Nikkor C 500mm f/8 was one lens that was born in that era. Even though buying one new was financially out of reach for me at the time, I kind of regretted not buying a Nikon just on the off-chance that one day I’d be able to afford one, or one of the many other exotic Nikkors.
Mirror lenses are just so damned cool!
What’s a Mirror Lens?
Mirror lenses or, more properly, catadioptric lenses, are lenses that combine conventional ground glass lens elements with curved mirrors. I have only ever heard of this design being used in telephoto lenses and telescopes, the most famous being The Hubble Telescope. They generally offer a lower weight-to-magnification ratio than do conventional lenses, tend not to distort the image, and have excellent colour transmission characteristics.
Light reflected from the object being observed or photographed enters the lens in the diagram above from the left, passing through the glass lens (tinted dark blue in the illustration — the mirrors are light blue), and then it bounces off the rear primary mirror toward the small secondary mirror fixed to the rear of the front lens element, and is again reflected back toward the eyepiece or camera through several lens elements placed in a hole in the middle of the rear primary mirror.
Having the light “folded” by mirrors is what makes these lenses so small and light for their magnification.
Here’s a brief timeline of Nikon’s 500mm mirror lenses:
- 1961: Nikon began selling mirror lenses with the introduction of the Reflex-Nikkor 50cm f/5.0.
- 1968: The f/8 version replaces the f/5, becoming more than one stop slower but this new model is much smaller, features coated optics, closer minimum focussing distance, and improved image quality.
- 1974: The f/8’s optics are updated with Nikon’s new multicoating (therefore the “C” designation in the lens’ name), improving image quality further.
- 1983: The “C” version is replaced by the “N” version. This lens is even smaller, with better lens coatings, and focusses to an incredibly close 5 feet, allowing for a maximum magnification ratio of 1:2.5! This high maximum magnification ratio earns the lens Nikon’s orange band on the barrel, signifying macro capabilities. This version of the 500mm Reflex-Nikkors offers the best image quality.
Note: Nikon also made 1,000mm and 2,000mm mirror lenses.
For more information, visit Nikon’s international website. They have 47 stories about the developement of select lenses and cameras in the section “The Thousand and One Nights“. The story of the Reflex-Nikkor 500mm lenses, with mention of other Nikkor mirror lenses, can be found therein.
Why Some People Hate Mirror Lenses for Photography
Well, where do I start? Some people are so dead-set against them and spout so many reasons to avoid them that one has to wonder if these critics are really vampires feeling threatened by the lenses’ mirrors.
Too Small and Light to Dampen Vibration: The first thing is that they are incredibly light compared to a lens of conventional refractory optics of the same focal length and magnification. For example, my Reflex C weighs only one kilo (2.2 pounds) compared to Nikon’s current AF-S Nikkor 500mm f/4G ED VR’s hefty 3.88 kilos (8.55 pounds). This makes the mirror lens easier to lug around and you can even use them without a tripod, but any vibration at all causes the camera to shake, blurring the image. This vibration-induced image degradation can happen even when you’re using a tripod with your camera’s mirror locked in the up position.
Fixed Aperture: Because this is a mirror lens, you cannot adjust the aperture — you’re always shooting at f/8 with this particular lens. Some people don’t like this restriction imposed by the catadioptric design. Most digital cameras were designed to be used with relatively fast autofocus lenses so a slow manual focus lens like this is a bear to focus accurately. Even if you have an old film camera that was designed for manual focus lenses, the slowness of the lens sometimes confuses the optical focussing aids.
Vignetting: These lenses sometimes cause the center of the image to be brighter than the edges.
They’re “Soft” Lenses: Nikkor mirror lenses tend to produce soft, low-contrast images… the older the version of this lens, the softer the image will be.
- Donut Bokeh: Probably the biggest problem people have with mirror lenses is the bokeh. In fact, to some people donut bokeh is the deal-breaker. Because light enters the front of the lens and there’s a small secondary mirror in the center, the bokeh is rendered as donut shapes instead of the generally-accepted-as-ideal soft circular bokeh. Even when there are no specular point sources that are out of focus, the lens tends to impose a pattern on out-of-focus backgrounds.
- Bad Luck: There’s a rumour floating around that if you drop a mirror lens and break it, you’ll get 14 years of bad luck because there are two mirrors inside. I don’t know if this is true but I doubt it… I just made this one up.
Why I Love My Reflex-Nikkor
If you’ll bear with me, I’d like to make my point primarily by addressing others’ criticisms of this lens and others that share the catadioptric design.
Too Small and Light to Dampen Vibration: Yup, they’re small, light, and even tripping the shutter can cause enough of a vibration to blur pictures (I’ll give you some tips on how to increase your chances of getting good images with this lens farther down in this post). That being said, my Reflex-Nikkor, which I affectionately think of as “Hubble Junior”, is compact enough so that I can carry it around in my gadget bag with all my other lenses and the total weight for the whole thing is around 20 pounds. With what I carry in my bag, I can cover everything from 180° down to 1.66° and can achieve better than a 1:1.36 magnification ratio. Hubble Junior is small enough that if there’s enough light I can very comfortably use it without a tripod for those times when there’s something I want to get a shot of but there’s a possibility my intended subject will drive, fly, or run away in the time it takes me to set up my tripod. Even if Nikon’s newest 500mm has image stabilization, holding a fifteen inch long, eight-and-half-pound monster (not including the camera) for any length of time is going to cause my scrawny arms to go into spasm. To me photography as a hobby should not be something that requires time with a personal trainer and a gym membership. These are not called “Recumbent Reviews” because I’m the type of guy who is willing to break a sweat in the pursuit of my art!
Fixed Aperture: This is true of all catadioptric lenses — there’s just no way to put a diaphragm at the proper optical spot. Mirror lenses tend to be pretty slow anyways so stopping down wouldn’t seem practical even if possible. I don’t have too much to say countering this shortcoming except that with such a high magnification lens with so little depth of field maybe fewer choices are a blessing in that the results are predictable… you just cannot overestimate your depth of field.
Vignetting: First of all, when I hear this “criticism” I rack my brain trying to think of a lens, catadioptric or otherwise, that does not exhibit some fall-off toward the edges, especially fully open. Frankly, I find that most of the time a little vignetting is a welcome thing and have at times added vignetting in Photoshop to help draw attention toward the center of the image (or away from the edges). Your image editing software might already have a filter to correct vignetting if it really bothers you.
They’re “Soft” Lenses: Yup, Hubble Junior’s a softy, alright. It also has next to zero spherical aberration, chromatic aberration, and coma. The guys who poo-poo mirror lenses are the same guys who give you numbers on how you can digitally correct these other aberrations in lenses that they love but a little softness and low contrast become major drawbacks when it comes to using mirror lenses. A little easily-corrected softness and low contrast are a small price to pay for virtual immunity to these other aberrations.
- Donut Bokeh: Sometimes there’s just no way around having donuts floating around in the background of your picture. They can certainly be distracting sometimes but, hey, that’s life — sometimes the picture just doesn’t work out. No matter what equipment you have, there’s a downside. A cellphone camera is great for quick snaps of you and your friends inside a car on a road trip but lousy for making giclee-quality prints. A technical camera is lovely for landscapes but not so hot for shooting sports. What I say is celebrate the donut! Work with it and you’ll get used to it and maybe even come to love it, like that one droopy eye on your spouse’s face. Donuts are not something to cause repulsion, they’re the mark of something singularly special!
- The Cost of the Alternatives: Let’s get real here… a used Reflex-Nikkor C will set you back somewhere near $300 and its N series younger sister maybe twice that. The current AF-S Nikkor 500mm f/4G ED VR has all the bells and whistles like autofocus, image stabilization, the highest quality glass and coatings, and adjustable aperture but it also comes with a Canadian price tag of $9,000. So the choice is yours… buy a $300 used mirror lens and add two minutes to your workflow correcting softness and low contrast in your image and deal with annular bokeh, or you can spend 30 times that amount for a new AF-S Nikkor 500. This is clearly a case of dollars to donuts! For a guy in my income bracket, there just isn’t anything to discuss here but if you’re a pro who needs this kind of magnification and autofocus so you’re sure to get razor-sharp images every time, by all means go for the AF-S. Maybe you can put it on your expense account or write it off your taxes or something.
How to Get the Most from Your Reflex-Nikkor
- Make Sure It’s a Nikkor: First of all, beware of professional reviewers who don’t like mirror lenses in the first place who then tell you which kind to buy. In my mind that’s a little like getting dumped by a woman and then getting a call from her offering to set you up with one of her single friends. She doesn’t like you enough to spend time with you herself so what kind of gremlin with a white corsage will be sitting in the coffee shop waiting for you on your blind date? Listen to people who own mirror lenses and look at their pictures. Ask them questions about how they took the picture and what they did in post processing. Get your hands on one before you buy if you possibly can. Avoid third tier lenses you never heard of until you googled “mirror lens”. Second tier companies’ mirror lenses might be as good or even better than my Nikkor C, but I just don’t know. I can only comment on what I own and use myself and I love mine, in spite of its shortcomings.
- Steady Your Camera: As I mentioned earlier, you’ll need either short shutter speeds or a solid support for this lens. The Reflex-Nikkor C comes with its own tripod mounting foot, and I suggest you use it. Pre-stress you tripod’s legs by flexing them outward once everything’s set up, use a cable release, and use your mirror lock-up function when shooting static scenes. Some people suggest using sandbags, but I’m not sure if you’re supposed to rest the camera and lens on top of them or drape them over the camera and lens when they’re fixed to your tripod. You might also want to experiment with different shutter speeds. I found that on the tripod I had problems around 1/30 second but at 1/60 or 1/8, not so much. I’ve also had trouble at 1/125 second. It might have something to do with how the vibrations propagate in my particular camera/lens/tripod set-up or I may have not been careful setting everything up onto the tripod. Try hanging your gadget bag from the tripod, too. Bump up your ISO setting as high as your tolerance for digital noise will allow you — this will let you use a higher shutter speed.
- Focus Accurately: Focussing is really tricky with this lens. First of all, you’re probably using a digital camera that was designed primarily to be used with autofocus lenses. The focussing screens of most modern cameras were not designed with slow or really fast manual focus lenses in mind. In the old days before autofocus, SLRs had focussing screens with microprisms and split-screen thingies built-in to help you focus. Many of you whose first camera was a digital might not even know what I’m talking about. I was having a lot of trouble getting properly-focussed images until I bought a special focussing screen designed for fast or slow manual focus lenses. I got mine from KatzEye Optics. Even with a special screen it’s really tough to get bang-on focus without a lot of practice. If you’re going to try using a long mirror lens with the screen that came with your digital camera, I suggest getting used to the lens by taking shots of stationary objects first. Focus in and out and you’ll see the area that’s in focus moving along the ground… do this until you have the in-focus part at the base of what you’re trying to shoot. When shooting something that’s moving, try to predict where your subject is going, focus on something that it will pass, and wait for your subject to arrive at that spot. Whether or not you have a special focussing screen, if you’re going to try focussing while using the camera handheld, good luck! Your best bet would be to brace the camera up against something, focus, and then try to frame your shot. Just be forewarned that at this magnification looking through the viewfinder of a handheld camera with a 500mm lens mounted, especially if it’s a “cropped format” like my D300 is, what you see through the eyepiece will look like something out of a really bad earthquake movie!
- Fixing Vignetting: If you really want to, there are a lot of software fixes for this “problem”. I have an excellent program that is primarily for correcting lens distortion that will also correct vignetting. It’s called PTLens and you can try it free on ten images. If you like it, you can buy it for $25. You don’t need to tell them HoaiPhai sent you because I don’t get a dime for referring you to their great product. By the way, you’ll find a bunch of Hubble Junior’s photos below and I didn’t correct vignetting or any geometric problems in them but I did enhance contrast and sharpness in most if not all of them. I also tweaked the colour in a few, just like I’d end up doing had I used any other lens.
- Fixing Low Contrast: The first thing I do to tweak a needy Hubble Junior image is to go into Curves, select a point on the line in RGB mode, and enter the following numbers… Input:15, Output: 0. Move the points on the line until you get what you want. If you’re intending to print the image, experiment with what value works best with your printer and paper. If you’re uncomfortable using Curves, just play with the Contrast and Brightness sliders… these are just suggestions, not The Eleventh Commandment!
- Fixing Softness: One thing you can do to avoid a soft image in the first place is to make sure there is not anything between the lens and your subject because it will be rendered completely out-of-focus and will soften everything. But these lenses do tend to be soft even in ideal conditions so when I feel the image needs some help I apply an unsharp mask as the final step before printing or saving in a web-friendly format. Here’s what I do… I convert the image to the LAB colour space and apply the unsharp mask only to the “Lightness” channel and use the following settings… Amount: not more than 50%, Radius: 1.2 pixels, Threshold: 1 level. Having said that I’m sure some Adobe-Wan Kenobi out there is going to say that I’m doing it all wrong. I’m not proud — I’ll gladly try your method in my constant pursuit for excellence.
- Donut Bokeh: Sorry, you cannot avoid this weird bokeh completely but you can minimize it by making sure your backgrounds are smooth fields without high-contrast detail or specular highlights. You could try filling in the donut holes and blurring the devil out of them in your image editing software, but that’s just silly. Embrace the donut! Maybe I’m biased because donuts are such an important part of the Canadian tradition and diet.
If you want an easy to use lens or you need a lens that will focus fast and accurately for sports photography or something, the Reflex-Nikkors are not for you.
In my book, this lens ranks as “Legendary” on the HoaiPhai Scale of Camera Stuff Approval, even though it’s devilishly hard to use. It was well worth every penny I paid for it. Here are some of my reasons why it gets such a high rating…
- They’ve been around for ages and it took me decades to finally get one.
- The magnification is incredible — I find this useful and a lot of fun.
- It’s light enough to go with me wherever I go.
- I’m very pleased with the images it makes and the donuts are just part of its charm.
- It’s hard to use and I’ve enjoyed learning the hard way how to use it — I find it very satisfying getting good results after having worked a bit to get to know this lens.
- It’s by far the cheapest route to getting a quality super telephoto.
The Field Test
I think I’ll let the pictures, and their captions, do the talking from here on in…
Hope you enjoyed this post. Let me know what you think about mirror lenses!