The Mercury Stereo system is compatible with hundreds of lenses from large format and medium format cameras. However, we are curating a much smaller list of recommended lenses that have been tested with the camera, work well, and produce outstanding results. Here are our most recommended lenses:

Here's a spreadsheet with all of the lenses that have been tested and are fully compatible with the Mercury Stereo 12 and Stereo M. It includes all relevant information about these lenses and their compatibility with various aspects of the Mercury Stereo system (filter size, compatibility with the Stereo Pano Camera, etc.). The Stereo Pano Camera is a special add-on to the Mercury Stereo system that takes the same lensboards, spacers, side handle, ground glass, and film backs as the Stereo 12, but shoots large large format panoramas and other images rather than medium format stereo. It allows you to make use of your complete Stereo 12 or Stereo M setup for large format use without reconfiguring anything. We mention it here because it is relevant to lens selection: if you would like to make use of your equipment for this purpose, you will want to source lenses that have the necessary coverage for this application.

Now let's cover some of our recommended lenses in more detail. We'll break them down by focal length class:

Historically speaking, because most stereo cameras lack interchangeable lenses, it's rather difficult to shoot ultrawide. This is especially true of medium format stereoscopy.

This is a real shame, as ultrawide focal lengths and MF3D are a match made in heaven. 3D photography is about space and depth, and of course ultrawide lenses are fantastic tools to emphasize depth. This is particularly true in stereo as wider lenses allow you to get closer to your subjects, capturing more gradations (planes) of depth at a given stereo base. You won't use ultrawides all the time, of course, but for the right subjects, and used artistically, they can produce amazing 3D effects unlike any other focal length.

One of the great advantages of the Mercury Stereo system is that you can shoot with true ultrawides.

A "true ultrawide" is a lens that doesn't use a retrofocal optical formula. Most ultrawide system lenses (such as Hasselblad, Mamiya, etc.) are retrofocal by necessity, as the camera (and often mirror) require the lens to sit farther from the film plane than is optimal for ultrawides. Retrofocal designs enable the lens to sit farther away, but at the expense of introducing many distortions and aberrations. Lens designers then have to introduce more lens elements to correct the aberrations, etc., until the lens is heavy and expensive, and its image quality has been compromised.

True ultrawides, by contrast, must sit very close to the film plane, but produce astounding image quality in a small, light form factor. This takes us to one of the most legendary true ultrawide lenses ever made, and the absolutely best available for medium format 3D photography:

Schneider Super Angulon 47mm f/5.6.

This is one of my favorite lenses of all time, and delivers the best ultrawide experience possible in 3D. It is roughly equivalent to a 24mm lens on a 135 camera. It's incredibly sharp, corner to corner (again, this level of sharpness is possible because it is a true ultrawide). It is designed to cover 6x9, and thus performs particularly well for 6x6. It has nearly limitless depth of field. It is compact, very light, and on a Mercury Stereo camera uses no spacer at all, making it the most compact configuration possible on the camera.

This lens uses the Stereo 12 "Copal 0" lensboard or Stereo M "Manual 0" lensboard.

Despite being one of the best lenses ever developed, the Super Angulon 47mm isn't insanely expensive, as it has been very popular for a long time. It can be had for $300 on the used market. Thus purchasing two for stereo use is not cheap, but it is within reach of many photographers.

Schneider released three versions of lens over the years. The original model is already perfect, and is the least expensive by far. The "XL" model increased the coverage so it could be used with larger formats. This isn't necessarily for Mercury Stereo cameras, so you can save your money. The final model, the "APO-Digitar 47mm f/5.6 XL" is the most expensive, and absolute best. However, it doesn't do much that the original version doesn't--it's hard to improve on perfection.

This isn't necessarily the first lens you should buy for medium format 3D, but if you want to go wide, this is as good as it gets.

An additional advantage of the 47mm is that it has just enough coverage to barely cover 6x12, which means that you can use it to shoot large format panoramas on the Mercury Stereo Pano Camera, using all of your Stereo 12 or M equipment, without any reconfiguration.

However, there is a great runner up in the ultrawide category: the Mamiya Sekor 55mm f/4.5. This lens was made for the Mamiya C line of TLR cameras from the 1960s through the 1990s. This was the most complex (in terms of optical formula) and most expensive lens in their lineup. It doesn't have quite the level of sharpness of the Super Angulon, and on your camera it isn't as compact, as it is actually a mildly retrofocal design. Your camera won't be as svelt as with the 47mm, but it is still a really excellent lens.

Of course, it isn't quite as wide as the 47mm lens either. For some photographers, however, this makes it slightly more practical for a larger range of subjects.

One big advantage of the Mamiya 55mm is that it comes in a matched pair already (for TLR use). This makes it quite economical: half the price or less for a pair than the Super Angulon 47mm. This is even more advantageous if you plan to use other lenses from the Mamiya TLR line (which I'll review in future updates). This lens uses the Mamiya TLR lensboard on the Stereo 12 or the Manual Mamiya TLR lensboard on the Stereo M.

In short, if you want the absolute best ultrawide lens available for medium format 3D, the Super Angulon 47mm is your ticket, and is affordable enough to be viable for many. If you prefer a slightly milder focal length or want the best value available, or plan to use other Mamiya TLR lenses, the Sekor 55mm is a superb choice.

For medium format stereography, 65mm is my favorite focal length, and I think the best fit for the format. If you could only have one focal length for stereo, this is what I'd recommend. As a mild wide, it is natural to compose with, but gives you a bit of extra "wiggle room" when shooting handheld, and intuitively leads you to get slightly closer to your subjects (good for stereo depth). At the same time, a mild wide gives you excellent perspective in depth: it looks normal, but subtly emphasizes the z-axis.

65mm generally gives you an extra handheld shutter speed to play with (30 instead of 60 with normal lenses). This makes an enormous difference in stereo photography, because it means you can shoot one f-stop higher than you ordinarily could, while still retaining a sharp image. Note that this particular advantage only applies to handheld shooting and moving subjects.

65mm also gives you excellent depth of field. While not as extreme as the ultrawides discussed previously, the large DoF provided by 65mm optics is palpable, and a significant advantage in stereo (where a larger depth of field generally enhances the depth of the image).

The Mercury Stereo system is compatible with quite a few 65mm lenses. I'll highlight a few here...

Mamiya Sekor 65mm f/3.5: This is from Mamiya's TLR line. It is a very capable and very inexpensive 65mm lens. I highly recommend it as the best value out there: like all Mamiya TLR lenses it comes as a matched pair. If you purchase one of these along with another Mamiya focal length (like the 55mm discussed in the previous update), you end up with two shutters and two different lens sets to use on your Mercury Stereo camera. This lens isn't as stellar as the 55mm, but for the reasons enumerated above, it is the most versatile focal length. Given its price, I'd suggest that it makes a great option for anyone considering Mamiya TLR lenses, or just looking for the best value. As a bonus, it is quite fast at f/3.5, which is an advantage when using ground glass (though you would rarely if ever want to shoot at this f-stop, as it produces minimal stereo depth).

Fujinon SW 65mm f/8: This is my favorite 65mm lens for handheld use on the Stereo 12. The lens is very light and compact, making for a lightweight, nimble Mercury Stereo configuration. The Seiko 0 shutters that house this lens are also quite excellent. As a newer lens than many other 65mm options, it is generally of extremely high quality. This lens is sharp and very intuitive to use. It also has a practical/common filter size of 52mm. The only downside to this lens is that it is fairly slow for ground glass work. Other 65mm are superior in this regard if you will be doing a lot of ground glass work. If most of your work is handheld, however, this lens just perfectly compliments the Stereo 12 or Stereo M.

Super Angulon 65mm f/8: This is a classic lens, and deserves its reputation. It will serve you well, with a sharp and beautiful image, and is quite small. However, it has a couple of drawbacks. For one, it protrudes a bit more than the Fujinon, negating some of its small-size advantage. More importantly, it uses the tiny Compur 00 shutter, which has fewer controls, is a bit more finicky to use, and tends to fail more often than larger shutters. Finally, many copies of this lens are rather old, which makes it more likely to need a good CLA. Still, this lens has a particular advantage: due to the small size of its shutter and front elements, custom stereo bases are possible with this lens, meaning that the lenses can be spaced closer together, enabling closer subject distances and larger usable negative/slide usage. For a select few, this could be a major advantage. We can easily make custom lensboards for you that narrow the stereo base when lenses (like this one) are capable of it. You'll need the Compu 00 lensboard for this lens.

Angulon 65mm f/6.8: Not to be confused with the Super Angulon, this lens has nearly the quality of the Super Angulon, at a fraction of the size and weight of that already-tiny lens! This lens is, frankly, a marvel. It will give you an extremely light and compact camera, and there's tons of room to create narrow stereo bases. While this lens also uses the Compur 00 shutter, with its limitations, here the use of the tiny shutter seems entirely justified and proportionally satisfying. This lens is particularly great for travel, when compactness and weight make a big difference.

Grandagon 65mm f/4.5: When considering pure optical quality, this is the best 65mm lens I've ever tested. Rodenstock's powerhouse lens was designed for large format (4x5) use, but it is razor sharp and delivers a completely distortion- and aberration-free image. It is also quite fast, a big advantage for ground glass work. It doesn't get any better than this lens for studio and controlled work. Unfortunately, this is a larger and heavier lens than all of the others listed here. It is less optimal for handheld as a result. Tradeoffs!

Other 65mm lenses are compatible with the Mercury Stereo system, and I encourage you to experiment with them and let us know how it goes! The above list covers what I consider to be the most distinctive options available in this focal length. Given the significant advantages of this focal length, the extravagant among you might even conclude, as I did, that you need more than one 65mm lens set, optimized for different situations!

In 6x6 terms, normal lenses (which roughly match the field of view of the human eye) are 75mm or 80mm in focal length. This is the 135 equivalent FoV of 45mm and 50mm focal lengths, respectively.

In stereography, normal lenses have one special property, and one historical tic.

Special property: Stereography is often linked to realism. Because viewing a stereo image makes the scene come alive in a manner wholly unlike flat images, giving the space captured in the photograph real dimensionality. This can make the viewer feel as if they are "really there." This effect is greatly heightened when looking through a viewer that (a) blocks out everything but the image, (b) magnifies the image enough to fill a large portion of the visual field, and (c) is capable of enough resolution to render fine details. The Mercury stereoscopes have all of these qualities, and are in fact designed to push all three of these attributes further than any other stereoscope of the past or present. Given these viewing conditions, a normal taking lens (especially if paired with our Ortho viewer) will closely match the depth and FoV of the human eye, giving the viewer's nervous system the illusion that they really are seeing what your camera saw, first-hand, as lived experience. Photographers who are going for this effect above all others like to use a normal lens to most perfectly create these conditions. Other photographers prefer to creatively explore compositions with different focal lengths, relying on the immersive realism of MF3D viewing to give a sense of being in a slightly unnatural (or hyperreal) space. And of course, others want both options in their toolkit. The Mercury Stereo system makes all of these possible.

Historical tic: There is one notch against normal lenses in MF3D, and that's that they are overused. This is simply a historical tic. Back in the heyday of MF3D (1920s and '30s), cameras were produced with many different focal lengths (though just one per camera). After WWII, however, very few medium format stereo cameras were produced. The Soviet Sputnik, released in 1960, was the only mass produced model since. It came with only one built-in lens option: a (pretty low quality) normal lens. Then, in 2007, when a flash-in-a-pan Chinese company called 3D World released an ambitious MF3D camera, they copied the Sputnik formula and offered it only with a normal (80mm) lens (better quality, but not at the level of the lenses I'm going to recommend here). For the most part, then, medium format stereographers haven't had much of a lens choice (except with custom cameras and twin rigs) since WWII!

Now that stereo photographers have many lens choices with the Stereo 12 and Stereo M, you can make your choices based not on availability, but on aesthetics. That said, a normal lens will remain a common choice, so here are some of the best ones out there:

Super Angulon 75mm f/8: This lens is a classic: sharp, compact, and lightweight. It pretty much sets the standard. It's only drawback is that it is slow, and thus most suitable for handheld work (where it is as fast as you'll ever need for stereo). For ground glass shooting, look elsewhere. This lens uses the Copal 0 lensboard, like almost all of the others in this post.

Grandagon 75mm f/6.8 and Fujinon SW 75mm f/8: These are top-of-the-line lenses by Rodenstock and Fuji. They produce exceptional image quality, with no vignetting or corner softness. Their main drawback is only in comparison to their 65mm counterparts (covered in my previous update). The Grandagon 75mm doesn't have the speed that sets apart the 65mm version, and the Fujinon 75mm lacks the extreme compactness of its 65mm version. If you don't plan on shooting a 65mm lens, these are fantastic options, and give you just a bit of DoF and FoV edge over 80mm lenses, but if you have a great 65mm lens set, you should probably skip these.

Mamiya Sekor 80mm f/2.8 (TLR): This lens deserves a special mention, as it is available very inexpensively as part of Mamiya's TLR lens lineup. As I discussed in the previous lens recommendations, this makes it a fantastic value. The value is compounded if you plan to get other Mamiya TLR lenses, as they can optionally use the same shutters. At any rate, this is one of the gems of the Mamiya TLR lineup. Though quality control can vary, most are very sharp. They are also quite fast, which is very useful for ground glass shooting. This lens can't produce the corner-to-corner perfection of the 75mm lenses mentioned above, but it is probably the best value out there, and is an upgrade over the 3D World optics. It uses the Mamiya TLR lensboard.

Apo-Digitar 80mm f/4: Now we come to the most modern, razor sharp lens available in the normal range for medium format stereoscopy. This was Schneider's attempt to make the sharpest lens possible for high-end digital photography. If you want the latest and greatest, this is it. Schneider's 90mm and 100mm lenses in this line are even better, but they fall outside the normal range, so I'll discuss them in a future update. The Apo-Digitar 80mm was a popular lens, and for something this good, it can be surprisingly affordable. Look for the deals! (Also, sometimes these come mounted in an electronic shutter. You can easily shift the optics to a Copal 0 shutter, but be sure to factor in the cost of the shutter itself.) This lens uses the Copal 0 lensboard.

Heligon 80mm f/2.8: Despite the impressive qualities of the Apo-Digitar, my favorite lens of this focal length is actually Rodenstock's lens from the 1960s. This lens went head to head with the Zeiss Planar 80mm f/2.8, and didn't fare well. That lens (which isn't compatible with the Stereo 12 or M; it is too large) produced more pleasing bokeh, which appealed to portrait photographers. Rodenstock's lens, however, was sharper, and also tiny, light, and compact. These qualities are all perfect for MF3D. I find this comparable to the Apo-Digitar 80mm in quality, but with an additional stop of speed for ground glass shooting. Also, though it is relatively rare, decent deals can be found on this lens. One thing that devalues it in the marketplace: it tends to suffer from slight element separation. This produces a rainbow around the periphery of the lens when you look at it from an oblique angle. However, this rainbow is not reproduced in your image, and I've seen no reduction of sharpness in multiple "rainbowed" copies of this lens. Nonetheless, this freaks photographers out and allows you to purchase this lens at an undervalued rate. The Heligon uses the Compur 0 lensboard. This is a very special lens if you are willing to seek it out!

There are more normal-length lenses compatible with the Mercury Stereo system, and I encourage you to discover and test more yet. I hope these recommendations, however, give you a sense of the options out there!

In general, longer lenses for medium format stereo are more difficult to use well. This is because they generally require greater subject distance, are more finicky to focus, and have narrower depth of field (DoF). All three of these factors lead to less stereo depth in photos. In general, then, the wider the lens, the more suitable it is for stereo. However, there are several situations in which longer lenses can serve you in an indispensable way, allowing for results that can't be obtained with wide lenses.

Lenses that are so good they're worth the limitations

As I noted above, the pinnacle of contemporary lens design for 80mm lenses is the Apo-Digitar 80mm f/4. As good as that lens is, the Apo-Digitar 90mm f/4.5 and the Apo-Digitar 100mm f/5.6 are even more amazing. They are the best of the Apo-Digitar line (except for a couple of specialty lenses). They offer a bit more coverage than the 80mm, which generates a more even field to eliminate even the negligible distortions at the far edges of the 80mm. They are also even sharper, making them the sharpest lenses available for MF3D. If you want the sharpest possible lens, especially for landscapes, and you don't mind the slightly longer focal length, these occupy the throne.

Hyperstereo

When you shoot subjects at longer distances, stereo depth is negligible at a standard (anatomically human) stereo base. In these cases, however, you can widen the stereo base. Because Mercury Stereo cameras can fire its two shutters independently, it's possible to take sequential hyperstereo shots, either handheld or (more precisely) with the Mercury Hyperstereo Base. Basically this exaggerates the stereo depth for faraway subjects, causing them to appear in rich depth when viewed. In this case, longer lenses tend to better capture faraway subjects, and the increased base counteracts the ordinary flattening caused by them. In short, if you plan to use hyperstereo, longer lenses are an important part of your arsenal.

Experimentation

Of course, even if longer lenses give you shallower DoF and less visible stereo depth, that doesn't mean that they can't produce really interesting effects, with or without hyperstereo! My hope is that the Mercury Stereo system, by making so many lenses and film formats available to the stereographer for the first time, will encourage experimentation. I'd love to see what you will do with longer lenses!

Some Compatible Lenses

Besides the top tier lenses mentioned above, there are a lot of inexpensive longer lenses available for the Mercury Stereo system. The venerable (and commonly available) Angulon 90mm f/6.8 is fully compatible and is a great compact choice.

In the world of high-end, medium format view lenses, 100mm is a special focal length. Whenever you see a 100mm lens, you can be assured that it was designed for medium format (usually 6x9) use rather than large format. This generally means that the lens is small and compact despite being high-end. This is equivalent to the Field of View of approximately a 60mm lens in 135 terms. All of these lenses are compatible:

• Zeiss Tessar 100mm f/3.5 (fastest but an older design; not as outstanding as the following)
• Nikkor-W 100mm f/5.6 (Nikon)
• Sironar-N 100mm f/5.6 (Rodenstock)
• Symmar-S 100mm f/5.6 (Schneider, earlier version)
• APO Symmar 100mm f/5.6 (Schneider, later version)
• Apo-Digitar 100mm f/5.6 (Schneider, ultimate version)

All of these lenses use the Copal 0 lensboard.

Mamiya TLR lenses

For those who are collecting lenses from the Mamiya TLR system, there are two further lenses worth mentioning: The Mamiya Sekor 105mm f/3.5 and the 135mm lens from the same system. Mamiya made four 105mm lenses throughout the multi-decade run of their TLR system. The first two are Tessars and quite unremarkable. They have not been tested with the Mercury Stereo system, but would likely work. The final one, the "DS" version, is the final lens released for the TLR system and added an aperture preview for the viewing lens. Unfortunately, this meant that Mamiya changed the actual lens housing, making it different from its paired taking lens. The two lenses are still compatible and can be paired on a Stereo 12 or Stereo M, but they will look different, and more importantly, the viewing lens cannot be easily unscrewed like all other Mamiya TLR lenses: it requires a spanner wrench to unscrew a recessed ring. In short, this will work but is a lot more hassle than the other TLR lenses.

The most desirable version of the 105mm, then, is the third version, which comes in a black shutter but doesn't say "DS" in red. The 105mm lens (3rd and DS versions) is special in that it is a sonnar design, created specifically for portraiture. It isn't as sharp as the other lenses listed in this guide, but renders a smooth and beautiful image. Again, this is probably most useful in the "Experimentation" category.

Also, the Mamiya Sekor 135mm f/4.5, though it is longer the maximum recommended focal length for the Stereo 12 or Stereo M, is a beautiful and generally very inexpensive lens, and if you want to experiment with it, go for it! It is fully compatible, and can actually use the same base spacer as the 105mm, making it particularly convenient if you happen to want to use both. (The 65mm and 80mm TLR lenses also share a base spacer, making them ultra-quick to interchange as well. I forgot to mention that earlier.)

Unlike all of the others lenses listed here (Copal 0), these TLR lenses of course use the Mamiya TLR Lensboard. Also, unlike the Copal 0 lenses, these have a limited coverage size and generally won’t yield any larger image than 6x7 when used with the Mercury Stereo Pano camera for large format mono work.

What about even longer lenses? As long as they are designed for one of the (many) shutters compatible with the Stereo 12 or M and they use a filter size of 58mm or smaller, they are likely compatible! Go hog wild! Just keep in mind that the longer the lens, the longer your camera needs to become to accommodate it, which can be unwieldy. In practical terms it probably doesn't make sense to go past 150mm. But that leaves a lot of options!

Many shutters require some minor modifications in order to mount to Stereo 12 lensboards. Our complete instructions can be found here. We can also perform shutter modification and mounting as a service.

The Stereo M, which uses manual lensboards only, requires few or no modifications to shutters and is easier and faster to setup. Instructions for mounting lenses to manual lensboards are lensboards are here.