Sony a6300 and Techart LM-EA7 II

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Sony a6300 with Leica 35/1.4 Summilux-M ASPH and LM-EA7 II

Sony a6300: love to hate you

There may not be any point, six months after the fact, to writing anything about the Sony a6300 compact camera. Well, maybe there is. Sony APS-C cameras are something that Fuji fans love to hate. And what’s not to hate from their perspective? Sony doesn’t make cameras that look like old rangefinders or SLRs, Sony lords it over Fuji with sensors that are slightly ahead (Fujifilm buys sensors from Sony, so it is not going to get the pathbreaking product immediately), Sony lenses are supposed to be terrible, and despite all this, Sony still outsells Fuji by an order of magnitude. How could this be?

— Sony strengths relative to Fuji in the mirrorless arena

The two possible answers are video and AF performance. Video on the a6300 is nothing short of phenomenal: 4K, 120fps HD, and just about every type of video gamma geekery that you could want. The Multi-Interface Shoe allows for some interesting snap-on microphone options, including XLR and wireless. The worst thing anyone has said about the a6300’s video is that it has rolling shutter problems, and the answer to that is really, so what? It’s an artifact of any mirrorless camera when used for video. And since Fuji sources its sensors from Sony, you’re not going to do any better. In fact, no one outside the Fujisphere considers Fuji’s video in any way significant.

The focusing speed and accuracy a NEX/Alpha has always been somewhat incredible. Even back to the old NEX-5, Sony could make lenses that silently and smoothly achieve focus on faces. The a6300 with its kit lens posts some insanely fast times, and Sony’s claims about continuous focus tracking are largely true, at least as far as this author has been able to reproduce the right photographic, ahem, “needs.” In fast action, a camera with poor lenses but a responsive system does much better than a more ponderous camera/lens combination that misses the forest for the trees.

One thing that is clear from the dpreview.com tests is that with whatever mystery lenses the site used to test the X-Pro2 and A6300,* there is almost zero difference in image quality, anywhere on the frame.

*Never disclosing the lenses used is dpreview’s second-biggest failing. The first is retconning itself into the time before the internet and digital cameras existed. Sorry. That was a mistake. The first is allowing itself to be bought by Amazon. Then the second is retconning. Then the third is mystery lenses (apologies to Steve Martin).

— Handling

The A6300 is fairly easy to handle. The grip section of the camera is substantial, and in general, it is easy to operate. No one, though, understands what the second command dial is doing on the top deck. It’s not comfortable to use with the camera at your eye. Controls are snappy and solid, as is the general build.

— Viewing

The A6300 has the latest OLED high-density electronic viewfinder that features a 2-axis level (pitch and roll) and more information display possibilities than you want to admit you want. Battery life is helpfully provided by percentage (and if there is one nice thing about Sony batteries, they are good communicators. Shooting does not black out in continuous mode. The EVF senses heat (infrared radiation); hence, its eye sensor does not react to glass-lensed glasses or sunglasses. If you don’t like the EVF, there is a big LCD on the back. Knock yourself out.

— Shooting

This is mostly unchanged since the a6000. The big thing is silent shooting, which uses a front and back electronic curtain (you can also choose electronic front or mechanical front). Silent shooting has two failure modes: first, in any situation with fast-moving objects, the progressive read of the sensor will cause typical “rolling shutter” artifacts. Second, dimmed LED lights (dimmed at the wall switch) flicker, even at full brightness, and can cause light banding in the finished frame (rolling shadow).

— Legacy lenses

One big note is that it is not particularly easy to engage viewfinder magnification on a shot-to-shot basis. You either have to learn to live with focus peaking or slow way down if you want to focus older SLR lenses, for example.

— Accessories and cutting corners

If you are accustomed to older NEX cameras, you will marvel at how Sony expects you to charge this camera with a USB connection to something else. The better solution is the Sony BC-TRW, which is a microscopic dual-voltage charger. It actually has four charging indicators (1-3 and off – meaning “fully charged.”). But yes, you still get a useless camera strap in the box.

 

An exit from the closed system

The problem with APS-C camera systems, whether Sony or Fuji makes them, is that they are closed, highly proprietary systems. You can’t stick a Fujinon on a Sony; you can’t get a Sony Zeiss lens onto an X-Pro2. Change systems? Get ready to pay the price when you sell your old system’s lenses.

There are two tired retorts:

  1. But the system has all the lenses you’ll ever need.
  2. Why don’t you just mount legacy lenses on an adapter?

The first argument is disposed of easily: what if you don’t like the one lens with your preferred angle of view and preferred maximum aperture? What if you don’t want to shell out for new lenses? What if you need the money for booze?

The second fails due to the kludge factor. Yes, it’s possible to mount other lenses on these bodies for use with cheap Chinese adapters and your old lenses. It’s also generally miserable. Both Fuji and Sony allow focus magnification, but Sony makes it difficult to use when a non-Sony lens is mounted. Both makes have focus peaking, but that’s not as definitive as you think. And although Fuji offers a phase-detect driven split-image manual focusing function, it’s not that much fun and not that fast to use.

The “out” provided by Sony was to enable phase-detect autofocus with third-party lenses. This enabled things like the TechArt LM-EA7 II adapter, which in theory allows the autofocusing of any M mount lens (or lens that can be adapted to M, provided it physically fits the adapter). If this works, it would be a game-changer, since it would bypass the usual foibles of adapted lenses (focus difficulty and inaccuracy of focus peaking being two big ones). Is this true?

The good, the bad, and the ugly with the LM-EA7 II

The adapter comes in a nice, foam-padded box and includes a NEX/E-mount body cap and rear lens cap. This is a nice touch, since people who bought the a6300 with a kit lens will have neither.

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50mm f/1.5 ZM C-Sonnar with LM-EA7 II

The good news is that with the sweet spot for Leica lenses: 35-50, the LM-EA7 works like a charm. The noise is a faint whirring, and the Sony phase-detect system fairly effortlessly computes and reaches the focus point (provided, of course, that your lens would ordinarily need 4.5mm or less of travel between infinity and minimum focusing distance).

Some observations:

  1. Focusing is through the lens, at shooting aperture. ***This forces the camera to automatically adjust for focus shift on fast lenses, again making the a6300 more accurate and repeatable than a Leica M body, which can only have accurate focus at one aperture.
  2. The camera plus adapter can focus on an off-center subject using (for example) wide AF. Face recognition works with this adapter, even though the adapter supports phase-detect only. ***This is significant because it means that the a6300 can more accurately focus fast Leica lenses on off-center subjects than a Leica body can.
  3. The camera plus adapter rarely misses, even off-center. In fact, the focus with things like the 50/1.5 ZM Sonnar (the modern version) is better than can be achieved with a rangefinder (naturally, due to focus shift).
  4. The adapter is serviceable with 75mm and longer lenses, provided that you pre-focus to somewhere at least near the expected focus point.
  5. The adapter, by virtue of its inbuilt extension, gives you slightly closer close focus with 35mm and shorter lenses.
  6. There is little or no color shift with adapted wides. Depends on the lens, but even the ZM Biogon 4.5 seemed to do ok.
  7. Flash works with the adapted lenses.
  8. The multi-shot vibration-reduction mode works (JPG only).
  9. The weight limit for the objective assembly (lens plus any adapters to M mount) is 750g. This is well beyond what you need for almost any Leica-mount lens and covers most DSLR prime lenses (if you go lens – to M adapter – to LM EA7 – to camera.
  10. The artistic effects, such as “Sad Clown with Single Tear Airbrushed onto Sweatshirt” still work with adapted lenses.

Now, what’s the catch? Well, there are seven.

  1. PDAF does not work for video, and the adapter does not do contrast-detect.
  2. Due to some clear limits in the Sony PDAF software (which is probably set up to look for big focusing changes), wide lenses (≤21mm) and lenses with maximum apertures of f/4 or smaller do not focus well. Granted, why do you need AF with these lenses?
  3. The motor part of the adapter hangs below the camera, making it hard to set the camera down. This is not entirely negative because it also makes a nice grip.
  4. Not all SLR mount to M mount adapters work. In general, you have to use the Leicaist versions because they taper enough to miss the motor unit. Konica AR is one of the couple that work with the adapter, and even then, it’s just the typical Chinese adapter with a relief milled into it to clear the autofocus adapter.
  5. Taking the camera’s aperture setting off f/2 or 2/8 tends to cause overexposure.
  6. The system for selecting and recording lens-specific metadata is confusing, pointless, and possibly both. Your best word may be to record everything as 15mm.
  7. It does take a toll on your battery.

Tips and tricks

  1. Disengaging AF. For some reason, there is a lot of internet kvetching about how it is difficult to disengage AF. This is probably based on old firmware that requires you to use Aperture Priority and turn to a small f/stop. It is actually very easy to disengage the AF temporarily. If you press and hold AE/AF-L on the a6300, the adapter will park at its “infinity” setting, the focus peaking will come on, and you can then focus manually. When you let go of the AE/AF-L button, the adapter goes back to normal AF operation (make sure the lens is set to infinity before you do this!).
  2. Quickly overriding face-detect or wide area AF. If you have the camera set to wide AF, and you press the center of the back wheel, it will go into spot AF, center area only. It will also automatically focus in that zone. There are many possible green boxes, so it’s not like spot AF – but it suffices in most situations where you need an arbitrary focus point.
  3. Minimum focusing distance. With a travel of 4.5mm, and the lens set to infinity, the adapter does not have extension enough to reach minimum focusing distance with any lens over 50mm. The slight exception appears to be some zooms, since their designs often obviate a direct relationship between focal length and extension while focusing. Minimum focusing distance, though, is all in your mind with the A6300, whose narrower angle of view causes you to back up to get the same field as with an FX/35mm camera.
  4. Prefocusing longer lenses. With long lenses the quickest and easiest way to get to a range where you can achieve focus is to press AE/AF-L (which parks the lens), turn focus peaking on, and focus to a point where focus is just behind the intended subject. Once you are there, let go of the AE/AF-L button to reactivate AF. Because you focused behind the subject, and because the adapter extends (thereby moving the focus point closer to the camera), you have now put your lens exactly in the right place. Needless to say, the longer the lens, the less frontward subject movement this technique will tolerate.
  5. Marking your close-focus point with long lenses. If you habitually shoot at 1-1.5m, find the right “parked” focus distance (see above) and then mark it on the focusing ring with a dot of colored paint.

Compatibility

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Konica 57mm f/1.2 Hexanon AR, shot by the Konica 35-70 f/3.5-4.5 Zoom Hexanon AR ($50), the “plastic fantastic” in its quasi macro mode, on the LM-EA7II.

Yes. In general the performance of this adapter depends on two major variables: lens weight and maximum aperture.  The former degrades focusing speed; the latter, certainty of locked focus. As noted above, Hexanons were tested due to the availability of an ulterior SLR adapter (plus I had a bunch sitting around).

  1. 35mm f/1.4 Summilux-ASPH M (pre FLE)
  2. 40mm f/2 M-Rokkor
  3. 50mm f/1.1 MS-Sonnetar
  4. 50mm f/1.5 ZM C-Sonnar
  5. 50mm f/1.5 Jena Sonnar (prewar)
  6. 50mm f/2.0  M-Hexanon
  7. 50mm f/2.4L Hexanon
  8. 50mm f/2.8 Jena Sonnar (with Amedeo dual-mount Contact to Leica adapter)
  9. 50mm f/2 Jena Sonnar collapsible prewar
  10. 50mm f/2 Carl Zeiss (Opton) Sonnar, postwar
  11. 75mm f/1.4 Summilux-M (prefocus)
  12. 90mm f/2.8 M-Hexanon (prefocus)
  13. 10.5cm f/2.5 PC Nikkor (LTM)
  14. 40mm f/2 Hexanon (AR) (Konica mount via Leicaist adapter)
  15. 57mm f/1.2 Hexanon AR
  16. 35-70mm f/3.5-4.5 Zoom-Hexanon AR
  17. 85mm f/1.8 Hexanon AR

Kinda. For wide-angle, medium aperture lenses the adapter does not do so well because Sony’s phase-detect AF isn’t set up to split hairs.

  1. 24mm f/2.8 Hexanon AR

No? Here, the details are too small and/or the depth of field too much to get an easy lock (or sometimes, any lock) with the A6300 [edit note: this appears to be due to the camera’s having difficulty in deciding where the focus point should be – and even in its “spot” modes, the a6300 is picking a focus point]. The behavior on these is more deliberate focusing, almost as if the camera had switched into contrast-detect].

  1. 18mm f/4 ZM Distagon [too wide, too small an aperture]
  2. 21mm f/4.5 ZM Biogon [too wide, too small an aperture]
  3. 21-35mm f/3.4-4.0 M-Hexanon Dual [too wide, too small an aperture]
  4. 50mm f/1.5 Carl Zeiss (Opton) Sonnar [aberrations that Sony AF can’t understand?]

Conclusion

The Sony A6300 is a pretty formidable camera for video and not a slouch for stills provided either that your style does not exact ultra high performance from kit lenses or provided that you are willing to invest in better Sony or Sony/Zeiss glass.

The LM-EA7II may never be good for sports or high-intensity moving work, but it provides some fun with old lenses, or as much of it as you can take! It’s actually a bit irritating that I did not have an A7-series camera on hand to try it.

Zoom lenses: good vs. not good vs. both

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This simple feeling… is beyond V’ger’s comprehension. No meaning… no hope… and, Jim, no answers. It’s asking questions: ‘Is my kit zoom lens good enough?’

In reality, we actually know little about zoom lenses except that the best ones (from a numerical standpoint) are very large, heavy, and expensive. Once you move into the enthusiast and kit versions, the question of whether or not they are good (or, more to the point, useful) is complex, subjective, and somehow optimistic.

General limitations

The struggle of zoom lenses, since basically forever, is designing a multifocal, focus-maintaining lens that is at least as good as any lens of the focal lengths covered, without being massively heavy or unimaginably expensive. This struggle is driven by four conditions of design, manufacturing, physics, and software.

  1. Design. Fixed focal length lenses have an inherent advantage because they are always going deliver high performance at low prices. Such lenses require computations at one focal length, have fewer parts, need less assembly labor, and require less glass. A zoom has to be good at a theoretically unlimited number of focal lengths between two extremes and has to maintain focus as it focal length changes.
  2. Manufacturing. The difference between a good lens and a great lens can be 0.01mm. Zoom lenses have numerous glass and precision molded plastic elements that have to work in formation at an infinite number of focal lengths between two extremes (say 14mm and 24mm). It is more difficult to make larger-diameter glass elements with great precision, and the more mechanical linkages exist in a lens (for example, ones that maintain focus through focal length changes), the more tolerances add up. Sometimes low moving mass and “slop” is built in to make lenses focus faster.
  3. Physics. More glass means more flare and dispersion, and zoom lenses have tons of glass. Flare can be mostly tamed via muticoating, but even so, dispersion adds up with the element counts. A 13-element lens with modern multicoating (losing ~1% per air-glass surface) can have a total loss of 25% of all the light coming into it.
  4. Software. This enters the picture in two ways: focus correction and image correction. On DSLRs and some mirrorless cameras, the AF Fine Tune function helps correct focus errors that occur with particular lenses and phase-detect autofocus. The difficulty with zooms is that the nature of focusing errors can change with each focal length, and dialing in a correction for one focal length for a lens can greatly improve images there but degrade images shot at other focal lengths. The second limitation arises in software correction of lens aberrations (distortion, vignetting/falloff, and sharpness). One cheat (or innovation, depending on how you look at it) is to let the camera make corrections that the lens design itself does not permit. This provides more freedom to design smaller, lighter, and cheaper lenses. But you can’t really reconstruct data that isn’t there – or bend it infinitely.

Why many enthusiasts have been suspicious of zooms

It mainly seems to be a thing with people 40 years old and up, who remember the bad old days. As to the history, in the 1970s, optical correction was not what it is today, and zooms got a really bad rap because things like the 43–86mm Nikkor were convenient but not optical superstars. The original zooms were two-touch, which allowed the easy setting of focal length and focus with two separate rings. If a lens mostly held focus as you changed focal length, it was a true “zoom;” if not, it was a varifocal (Nikon is, and long has been, an offender in calling varifocal lenses “zooms”). Zooms of that era were difficult to design, and it was a time where lens design was transitioning to more computerized methods. They worked for a lot of purposes, but given the natural male inclination to over-spec and compete with equipment, they were not taken very seriously.

In the late 1970s, manufacturers went to one-touch, where you could adjust focus and focal length with the same grip. The temptation was to conclude that you could just re-zoom, re-compose, and fire away, but the reality was that focus drift followed focal length changes, and if you didn’t bother to refocus, you could get slightly soft pictures. One-touch zooms also suffered from zoom creep: eventually, as the lens loosened up, pointing the camera up or down would cause the zoom mechanism (governed by front-back movement of the ring) to move on its own. This too, did not help perceptions, though there are some very good zooms of the 1970s and 1980s, including some third-party offerings like the Vivitar Series 1.

SLR manufacturers rediscovered the two-touch in the 1990s, when it became an advantageous design for autofocus lenses (an AF motor could turn a focusing ring but not also a zoom ring). And that is when they all backslid into selling varifocal lenses as “zooms;” the assumption being that the camera’s AF would correct the focus anyway. Although questionable from a marketing standpoint, autofocus helped assure that the new “zooms” would  be

The rise and fall of zooms (1999-2005)

If zooms had a heyday, it was from the late 1990s to the mid-2000s. Several things came together to make this happen:

  • Vis-a-vis prime lenses, zooms were more heavily telecentric than prime lenses. In simple terms, their design created the straight-on light rays that digital sensors like.
  • Advances in lens coating took away some of the performance penalties of using a large number of lens elements for image correction.
  • Prime lenses were getting little in the way of updates. This meant that the best ones were standing still, and others did not work as well as zooms with digital. Consider that it took Nikon 50 years to update the formula of its 50/1.4.

The prototypical lens of this era was the AF-s 17-35mm f/2.8 Nikkor, which was designed for the D1 cameras but was usable with contemporary film cameras too. This lens outperformed most primes within its focal length range, was solid, fast-focusing, and very  popular.

But just as every pendulum swings, the 2010s to the present are where the optical (but not necessarily total) performance level of cheap zooms took a little bit of a dive.

  • In a market with softening demand, maintaining competitive MSRPs for entry-level cameras and lenses required simpler and cheaper designs.
  • The processing power of digital cameras increased to the point where it became possible to correct for distortion, light falloff, and sharpness in-camera.
  • Increased emphasis on video, especially from mirrorless, demanded lenses that could focus quietly and continuously, driving toward lower moving mass.
  • The move by the market toward camera phones meant that the “burden” associated with separate cameras had to be minimized.

In other words, the ethic was (and is) using technology to make cheaper, lighter, and easier-to-make lenses acceptable, not so much to make good lenses better.

At the high-end of the lens lines, updated primes also began to exert pressure on the more expensive zoom lenses, especially where trends push toward small and light.

What is the quick and dirty way to identify “good” zooms?

When shopping for a zoom lens with high potential, this is the general hierarchy to predict (with some but not total certainty), where a lens fits on the performance curve.

— By effective aperture

  • Constant f/2.8 aperture – this generally means a pro-level lens. It also means big, heavy, and expensive.
  • Constant f/4 aperture – this is the high-end amateur or lower-end pro zoom. It takes a lot of engineering to keep the aperture constant on a zoom, and this type of lens generally has the best balance of performance, weight, and cost. Canon and Nikon both make this style of lens. These are not cheap, but they are much easier to live with than monster pro zooms.
  • Variable f/2.8-4  or 3.5-4.5 (1 stop aperture shift) – this lens type of lens generally has been optimized for compactness over speed. F/2.8 is really a bragging right; it’s only half a stop faster than f/3.5.
  • Variable f/3.5-5.6 (or f/6.8) (1.5+ stops) – when a manufacturer lets the maximum aperture float this much, it is generally an indicator that you should not be expecting world-beating performance. But you will get a lens that will do well in most circumstances and not break your back or budget in the process. These are actually the lenses that are fun to shoot with.

— By zoom range

This may sound deceptively simple, and maybe it oversimplifies, but it is a fairly good bet that where a modern lens has a zoom range of greater than 2.5-3x from short to long, it is is probably a “convenience” zoom rather than one oriented toward absolute performance.

Can “not-good” be good?

Yes. Despite having performance a notch or two below pro lenses, kit zooms can be quite good within some limits. First, in an era where photos are overwhelmingly likely to be shared on social media, and not printed, kit zooms are actually complete overkill. In fact, anything beyond an 8mp iPhone 6 might be complete overkill – the same way that a lot of expensive pro equipment in the 1970s was used by amateurs to generate 3.5×5 inch prints.

Second, even if you print, you only need about 6mp of real-world performance out of a lens to print a nice 8×10, which again is bigger than most prints made today. “Real world performance” means type of system resolution that DxOMark measures (lens performance plus body performance, moderated through focus accuracy). That might be a 12mp body and a midrange lens.

Third, you will still get really good results – though optimum performance may be ~3 f/stops from wide-open (f/8 vs. f/3.5 maximum) as opposed to (f/4 vs. 2.8 maximum). There is an old adage, “f/8 and be there,” but in reality, once a lens is stopped down even to f/6.3 (let alone 8), even a plastic meniscus lens will have performance approaching an expensive coated lens. Like vampire tears, the pro-lens advantage evaporates in bright sunlight.

Finally, especially for mirrorless cameras, some lenses have video performance that vastly outweighs whatever perceived deficiencies they have for other purposes. For example, you might conclude that the 16-50mm f/3.5-5.6 power zoom lens that comes with a Sony a6300 is terrible. It’s not terrible for still pictures (in no small part because it is one of the fastest-focusing lenses ever invented), but it really shines in video, where it can silently and reliably track moving subjects without introducing noise. And it’s also tiny.

Conclusion

To wrap up: the performance, utility, and fun factor of zoom lenses is actually pretty subjective. Try as many as you can. Pick the one that you like the best, so long as it does what you need it to do.

 

Konica M-Hexanon 28mm f/2.8

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The 28mm M-Hexanon, like the its focal length, occupies a strange space that is neither here nor there. I have never had good luck with 28mm lenses, if only because the angle is a little wide to be comfortable for close shots of people and a little narrow for some of the landscapes I shoot.

Only on the verge of selling mine (for lack of use since way back when I had an M8) did I shoot a bunch of tests with an M typ 240. This particular lens had been recollimated to be at exactly Leica spec (most lenses made before the M8 were not set up to hit the center of a flat sensor).

This piece will not editorialize much but instead show it like it is. Which is quite good, far better than I had remembered.

First, the obligatory “how sharp at a meter” exercise. This is f/2.8.

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Next: does it shoot good pictures of children? Yes.

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E poi – how is the bokeh? Strangely, it’s actually really good, especially for a wide lens. Here is the sequence f/2.8, 4, 5.6, 8.

Sunstars? Got ’em too. Here is f/2.8-8 (clockwise):

Gross resolving power (again, f/2.8-8):

And now, we laugh at your Elmarit-M!

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Flare resistance, same range:

Spherical distortion:

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Another test; can’t remember why. Seemed like a good idea at the time.

 

General verdict:

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Will the real infrared photography please stand up?

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The strange thing about infrared photography is that it represents a very small piece of photography in general, but there is apparently no space in photography so small that it can’t support some form of snobbery. And in infrared photography, it is the idea that there is “near” infrared versus “true” infrared. Not only does this convey a false sense of exclusiveness to people who shoot 850nm and up, it’s also not accurate.

When you shoot a normal camera in daylight, there is a small amount of infrared contamination – it’s about 10 stops less than daylight, or coming in at 1/10 of a percent or 1/1024. Tiny, even on something with big infrared contamination like a Leica M8. So any particular shot is overwhelmingly lit by visible light.

A dark red filter (RG630, 091, 8x, #29, etc.) flips the equation: the average blockage of visible light is 3 stops, or 75%.The reality is that most skylight scenes are predominantly blue, and this filter cuts a lot more than three stops. Even if you are shooting objects that are middle grey, these filters reject 75% of all light – meaning that when you shoot them on a camera with no other IR rejection, deep red and infrared light make up 75%+ of the light. The false color you are obtaining is infrared light that is still being blocked in part by green and blue squares on the Bayer filter on the sensor.

The case for the “near” classification is even weaker with the 695-720nm filter (RG695, 092, R720). First, consider that wavelength ratings on filters are at the 50% mark. So a 720nm filter really starts passing 100% of its light around 750nm. On a short exposure, which you will see is commensurate with a normal visible-light exposure, infrared light is providing almost all of the illumination.

Going the other way, “true” infrared is not that advantageous – and may not be something to commit to in an IR conversion. First, even though the Bayer filter does not affect 830nm+ light, the decoding algorithm in your camera still compensates for it. So if you dump the RAW file into DCRAW, what comes out still has something of a checkerboard pattern. Second, the false color effects generated by mid-band IR actually allow for more contrast control because there are multiple channels of useful information (and with 850nm+, you really need this, since everything likes to come out bright white in sunlight, especially around dusk). Eliminating this effect means that you have less ability to rebalance the tones in a scene.

None of this is to say that it’s good to meet one form of snobbery with another technical one. But let’s just keep the infrared world big, okay?

# # # # #

50mm f/1.5 Zeiss Sonnar (1937): first

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Above: Zeiss Jena 5cm f/1.5 Sonnar (prewar; 1937 example of the 1932 design) on a Leica M typ 240 with an Amedeo dedicated 50mm adapter. This particular lens is almost 80 years old.

1. The story

The derivation of the trade name “Sonnar”(which may have less to do with Sonne than being a portmanteau of Sontheim am Neckar) reminds one of the the way that the Mr. Sparkle is a joint venture of the Matsumura Fishworks and the Tamaribuchi Heavy Manufacturing Concern. Be this as it may, the Sonnar had but one goal in life: crush Leitz’s fast lenses in an era where ISO 12 film was the norm. And that it amply did. Even today, the performance of this uncoated lens is impressive.

When the Sonnar arrived in 1931 (f/2.0) and 1932 (f/1.5), the Tessar (or Elmar) was the gold standard in normal lenses: a well-corrected triplet that, in an era lacking anti-reflective coatings, sneaked in a little more correction by cementing two pieces of glass together. When it came time to exceed f/2.8, though, the real competition began:

  • In 1889, Paul Rudolph, working for Carl Zeiss, determined that the best balance of contrast, correction, and cost was a three-element lens called an anastigmat (trade name: Protar).
  • In 1895, Rudolph invented the Planar, which was a highly-corrected symmetrical lens. It was shelved soon thereafter, no doubt on account of the low contrast that occurs with many air-to-glass surfaces.
  • In 1902, Zeiss released the Tessar, which provided more correction than an anastigmat (by adding a fourth element glued to the the third) without increasing the number of air-glass surfaces. The Tessar was technically inferior to the Planar, but it did not have the two extra air-glass surfaces (each robbing 10% of the light, compounded).
  • In 1925, Max Berek modified the Leitz Elmax, which had a 1-1-3 (cemented) arrangement into the Elmar, which bore a heavy resemblance to the Tessar, allowing for a good 35mm-format lens with fewer elements and less assembly labor.

In parallel universe (but still orbiting around Zeiss)

  • In 1916, an American (Charles Minor) started adding elements to the triplet, but just in the front. The result was the Gundlach Anastigmat, which had a blazingly fast f/1.9 aperture. The contemporary ads show that this was actually a cine lens.

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image credit: Central Camera 1936: Gundlach, Ultrastigmat, Bausch & Lomb, Verito Lenses; Packard via free images (license)

  • In 1922, Ludwig Berthele, working for Ernemann (of Ermanox fame) continued elaborating this into the Ernostar, which became on of the first plate lenses to hit f/1.8 (in 1924).

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Scan used by permission of Peter Naylor.

  • In 1926, Zeiss bought Ernemann and acquired Berthele in the deal.
  • In 1931, Berthele made the first f/2 Sonnar, which was a new lens with an old name. It was for 35mm format and had a 1-3-2 arrangement, with the second and third group cemented together.
  • In 1932, he made the f/1.5 version, which added an extra element to the rear group.
  • In 1936, caught off-balance, Leica licensed the Xenon, a symmetrical Double-Gauss design from Schneider, licensed in turn from Taylor-Hobson in England (the Series 0), in turn had been cribbed from the 1896 Planar.
  • In 1944-1945, the Zeiss plants were bombed back to the stone age.
  • In 1949, the Xenon was updated with coagulation-style lens coatings and became the Summarit.
  • In 1950, the Zeiss-Option Sonnars came out with a new computations.

The circle was now complete: the entire high-speed lens space was dominated by Zeiss designs and would continue to be – for pretty much all time. When you stop and think about it, until the advent of things like the 50/1.4G Nikkor, the history of high-speed lenses had been nearly nine decades decades of Sonnar and Planar clones.

Why did the Sonnar do so well? It’s not so complicated. It all boiled down to the number of air-to-glass interfaces. The classic triplet (the anastigmat) represented the best balance between correction, contrast, and cost. But adding more elements (to get more correction) meant more air-glass interfaces. And that meant less contrast and more flare. Zeiss increased the correction by cementing additional elements together to make a total of three groups. Leica could not do this because it did not have the intellectual property rights to do so. During WWII, Zeiss dabbled in coating its super-speed lenses, but it was not even really necessary given the Sonnar’s high transmission.

2. Using one today

These days, the Contax rangefinder is almost dead, 35mm film photography has gone all “Tony-Bennett-in-the-late 1990s,” and so the only place you’ll likely be using one of these is on a Leica body. Fortunately, it’s pretty easy to do. You just need the appropriate adapter. These are not particularly expensive for APS-C (although they do incorporate focusing helicoids); they are more expensive for Leica cameras because they need a mechanism to translate the movement of a 52.3mm lens to a camera whose rangefinder mechanism wants a 51.6mm normal lens (how two German companies known for their precision could get so sloppy about what constituted a “50mm” lens is baffling – but being a big-name German optical company means never having to say you’re sorry….).

By far, the best adapters for Leicas are made by Amedeo Muscelli, and of those, the best is that dedicated adapter for Contax 50mm rangefinder to Leica M. This is  not the usual lens with the reproduction of a Contax helicoid and focusing scale; rather, combines with the lens to make a unit that looks a bit like an old Elmar (allowing, of course, for the streamlined – dare we say phallic) shape of a Sonnar. The dedicated adapter focuses in the same direction as a Leica, at almost the same rate of distance change per unit of turn, and it has a lever, which can be critical if you are using a collapsible Zeiss lens (since with a traditional adapter, you are grasping the lens barrel to focus – something you can’t do with a collapsible lens). When your lens is dialed in, this adapter focuses amazingly accurately right down to 0.6m – a lot closer than any Contax did.

And how do you dial one in? If your lens is front-focusing, the simple answer is to remove the lens cell from the Contax barrel and unscrew the rear group slightly. It is never more than 1/4 turn, and you can maintain the setting by wrapping the threads of the rear group in Teflon tape and screwing it back in. Back it out about a 1mm (circumferentially) at a time, and check the focus on near and far objects. Do note that where a Sonnar has a lot of focus shift, you’re going to have to choose whether to

  1. Have the lens front focus at f/1.5, reach focus at f/2.8-4 ,and hit focus at f/5.6 and smaller
  2. Have the lens focus dead-on at f/1.5, miss at f/2-4, and become usable again at f/5.6 and on.

3. Observations

The first observation is that finding a prewar f/1.5 Sonnar that is not totally trashed is not particularly easy. Fortunately, at least cleaning marks are not an issue on uncoated lenses unless someone used Soft Scrub as an optical cleaner. Which does happen from time to time.

The second is that in the central part of the frame, this lens is very, very sharp. It has decent performance at f/1.5 if you optimize for that aperture, loses precise focus from f/2.8-f/4, and comes roaring back at f/6.3. If you keep with the original collimation (or an approximation of it, you get really sharp pictures around f/2.4, getting better through f/8.

The third is that the coatings on postwar Sonnars are not moving the ball much in terms of performance. Because this was the last fast Sonnar I obtained, it’s easier to compare this to the 1961 Carl Zeiss version. The 1937 model performs similarly in most ways. It is very slightly softer, with contrast that is almost at the level of a 1977 Jupiter-3.

Flare is only slightly improved by coatings, and they do not resolve the “rainbow circle” flare that afflicts every Sonnars (even multicoated Sonnetars) when a point light source is just out-of-frame. The one unique failure mode is strong side lighting (from the looks of it between 75 and 90 degrees to the lens axis), which can cause a veil across the entire surface. This also happens to a lesser degree with postwar Sonnars and copies, just not quite to the same degree.

Overall performance is strikingly close to the postwar, if you allow for slightly improved spherical aberration on the older lens. The postwar version is a tiny bit sharper, but seems clear that this comes at the expense of bokeh, which goes from smooth disks to ringed disks. If you care about that stuff.

4. Roy Batty

The f/1.5 Sonnar was the proverbial candle that burned twice as bright, and by 1962 it was essentially extinct. The “twice as bright” part is doubly applicable to the 1960-1962 Car That it was so widely copied in the postwar era is puzzling. Granted, German patents were handed over to the Japanese, but in terms of sheer performance with coatings, there were already better lenses to copy (like the Xenon). Canon, Nikon, and Zunow all made their own versions. The Soviets made one too. Perhaps there was a “prestige” element to the Contax that was desirable to copy (though you would not have the all-important brand name). Or perhaps there was something about the mechanical design of a 3-group lens such that the cost of machining extra parts for 6 groups cost more than triple-cementing rwo groups. The world may never know. The fetishization of the Sonnar did not really get started until the mid-2000s and by then, it was based more on imperfection and “look” than a perception that it was actually better.

Conclusion

The prewar f/1.5 Sonnar is a worthy lens, though its relative scarcity does not exactly make it a value leader compared to postwar variants. As with any 50mm Sonnar, as long as you take care to control the placement of light sources, it can be another creative tool, if not a broader-use lens.

Canon 50mm f/1.2 LTM: not screwmounting around

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As you contemplate modern lenses, It is difficult to associate these optics with the proud civilizations that created them: Tokyo, Rochester, Sendai, Jena. They worshipped image quality, because it is strength that makes all other values possible. No picture survives without it. Who knows what delicate objective lenses have died out of the world, for want of the strength to continue. 

It’s a long way from the Canon 7sz to Andre Agassi, from the Serenar to the EOS Kiss Merkur XR4ti (…or whatever the amateur model of the week is). Canon used to be a hard-core producer of Leica knockoffs, many of which were more functional, convenient, and reliable than the rickety prewar designs that Leica kept elaborating. The Canon P was a standout, as were the VI-L and the 7 series.

The Canon 50mm f/1.2 (September 1956… can you believe that it is now almost 60 years old?) was the company’s penultimate halo lens. It came out with the VT (not Deluxe), and it would not be surpassed until 1961 with the Canon 7 and its 50/0.95 Dream Lens (from a size, weight, and cost standpoint, dream is clearly defined broadly to include nightmare). Ironically, the 50/1.2 cost more than the 50/0.95. Modern Canon lenses are quite good, but they don’t have that certain fun factor to them.

Synergies. This is a new thesis on my part, but I am starting to suspect that the M typ 240 and 246 tend to interact with lenses in ways that might not be immediately intuitive. Some lenses seem to work unexpectedly well with the color sensor (possibly the demosaic-ing algorithm accidentally boosting sharpness). Many lenses work better than expected with the Monochrom camera — likely because the color-bind sensor is not bothered as much by chromatic aberration. The “why” these things happen is probably insoluble; it is merely interesting that they do. And yes, some dog lenses do stay dogs, and some lenses have bad corners to f/8. Nulla regula sine exceptione.

Look and feel. Perhaps “Carré Otis” is the best way to express the relationship between the size of this lens and Canon’s more common 50mm lenses (2.8, 2.2, 1.9, 1.8, 1.5): generously proportioned, slightly flaky, and exhibiting certain, ahem, virtues.

The finish of the 50/1.2 is typical mid-to-late Canon that came into vogue in February 1956 with the 50mm f/1.8 mark II: a black enamel focusing ring and sandblasted chrome aperture ring and distance/DOF scale. This is much more pleasing than Canon’s contemporaneous all-black lenses (like the 35/1.5, 35/2, 100/3.5, 100/2, and 135/3.5), whose finish looks good in smaller lenses and feels chintzy in larger ones. But the affect with the 50/1.2 is solid. It will keep your M typ 240 on balance.

The focusing effort is heavy, and even the aperture turning is heavy. Unless, of course, lubricant has leaked out onto the aperture blades. The focusing pitch is very slow. Even the interesting push-button infinity lever takes a deliberate effort to dislodge. Is there a problem with any of this? No. Will you have issues tracking fast motion or switching from near-to-far subjects (or vice-versa) as if you were a D700? Yes.

Flare and use with filters. The first thing you have to remember with this lens is that you are dealing with an SLR-sized front element that sits very close to the front of the filter ring, seven elements, and single lens coatings from the mid-1950s. This isn’t going to flare, right?! Really, cleaning marks are the least of your problems here.

The big (physical) hazard with this lens is filters – as in don’t tighten down a filter without checking the clearance between the filter and the front lens element. If you want use conventional filters, you will likely need to use an empty ring as a spacer or fit a rubber o-ring around the threads on the filter. The only alternative is to use Canon RF filters, which are expensive and present a flush glass surface on the front of the lens. Not only does cabin your choices for lens hoods, it also presents ample opportunity for sidelight flare. Like the picture below (and let’s be fair – this is shot outdoors with floodlights everywhere). But be sure to use some kind of hood if you can.

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Canon filter ghosting (at f/1.2). All hell is breaking loose here (not surprising with Christmas lights a scant two feet from the lens), but it’s not all bad, given the motif:

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On balance, it is better to use a filter if you don’t want to deal with the rickety Canon metal lens caps, which never want to stay on. Just watch how you use it, and if you can space it correctly, consider an MRC.

General optical performance. On an M, at 24mp, the 50/1.2 really acts like Beauty and the Beast. At its largest aperture, it has microscopic depth of field, though with practice, you can tell where it is going to land. It does what most other super-fast spherical lenses do: it front focuses at wider apertures and settles down at middle ones. Every one of the three copies I have owned seems to have had slight differences in the midpoint of depth of field at close ranges and large apertures, which is not surprising. But this is par for the course; all fast 50mm lenses are testy on Leica rangefinders. As you start stopping down, the 50/1.2 becomes exponentially sharper. F/1.4 is light years better than 1.2; f/2.8 is orders of magnitude better yet.

Rather than dragging through every optical trait one at a time, let’s take it at f/1.2. Soft contrast, heavy vignetting, reasonable resolution of details, with a field that seems to curve at the edges toward the camera. This vignetting persists, even when the lens is coded as a Leica Noctilux. To be fair, this was more than enough for most 35mm film use. A lens like the Canon 50/1.2 would be used at night, where contrast would be high. It was not designed for thin depth-of-field fetishism. You can click on the picture below for a full-sized image.

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The picture at the top of this article is also shot at f/1.2. In terms of controlling bokeh, if you are into that thing, this is yet another lens where your best bokeh is achieved by (a) getting the subject as close as possible and (b) getting the background as far away as possible. Not to belabor a point from the previous article (on the MS-Sonnetar), but an easy and almost unavoidable rule of thumb is that the better a lens performs wide-open, the worse the bokeh. The list of these suppressed lenses is long and distinguished: this Canon, almost every Noctilux, the Hexanon Limited, the Nokton 1.1, the Nikkor 1.1, and basically any lens faster than f/1.4.

The next click, f/1.4, is a touch more contrasty, and is still a good setting to use in harsh nighttime conditions. Take a look at the field curvature here – there is no way the Gummi Bear wrapper should be so close to being in focus like the boys. Actually, it seems unlikely that both boys should be in focus, but there you have it. And here you also have the bokeh vibe. As in vibration.

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Just for fun, below is one shot wide-open with an M8 (you can click on it to see it at full size):

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Stopping down to f/2 gives better results yet – and the focusing point is now exactly where you would expect it to be. And here is your bokeh test outdoors. This is essentially minimum focusing distance with a background that is 50m away.

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At f/2.8, the lens is starting to hit its stride. Especially with the M set for emulation of the Leica 50/1.2, the lighting evens up, the sharpness goes up significantly, and the field flattens a bit. Although this begs the question of getting a slower lens and shooting more wide-open, with these old lenses, you are often better off with a fast lens stopped down than a slow lens wide-open. Also, the big old glass looks cooler and makes child ward nurses less likely to think you are using some kind of super-high-tech digital camera to document medical procedures (when you’re actually just bored).

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At f/4, performance starts to max out (like the 1.2 shot, you can click on the one below to get a full-sized image). You almost go into double-take mode because a good example of the lens looks sharper than lot of modern glass. I’m thinking particularly of the 50/1.4 AF Nikkor, which the Canon crushes – and likely because the Nikon is usually tied to a somewhat limited AF system (phase detect systems seem pretty much incapable of compensating for the focus shift that occurs when a lens stops down).

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F/8 is where performance starts to degrade a little bit (see the full-sized image). Sharpness starts to decline. People take on cartoonish, ascetic, or vampiric features. Bring your gloves, lightsabers, and garlic.

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Conclusion? This lens was sold as the premium lens on a lot of Canon cameras – and in some ways a “bragging rights” lens vis-à-vis Leica and Nikon. The performance at f/1.2 is reasonable but not world-beating; but given limits seen even in digital M shutters (1/4000 sec), you would rarely be trying to shoot this lens wide-open in daylight. At least absent a neutral-density filter.

The pricing of this lens is all over the place; super-clean examples (from a cosmetic standpoint) seem to command a hefty premium, but almost all will exhibit microscopic scratches (cleaning marks), and oil haze is a recurring theme (and it is fairly destructive to these lenses’ coatings). But as with a lot of things, cosmetics are not indicative of performance; you never know whether a lens has been abused over the years until you actually try it.

Be ready to poke around through multiple examples to get one that works really well; keep an open mind about the condition of the coatings; what makes these lenses flare badly has little to do with the coatings but rather with the hazards of having that really big front element.

MS-Optical 50mm f/1.1 Sonnetar: magic time

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The MS Optical Research Sonnetar is like The Life Aquatic with Steve Zissou. You either get it or you don’t, and if you don’t understand Jacques Cousteau, Willem Dafoe playing a subservient gay German, or Wes Anderson in general, there is no one who can make you like it. By the same token, if you drive Jaguars, no one with a 276hp front-drive Camry is ever going to win you over by telling you it has a higher thrust-to-weight ratio than an XJS V12 with the flying buttress hard top.

You don’t buy a Sonnetar as your only 50mm lens; in fact, you don’t even buy it as your only fast 50mm lens (and by the way, 50s should either be fast or fun – there is nothing more bland than a 50mm Summicron). The Sonnetar has strange controls for most (the rotating front barrel is exactly like using a Contax or Nikon rangefinder). It vignettes like crazy. At any distance, you can have your choice between correct focus and optical correction.

Why would anyone like it? It’s actually a big question whose only easy answer might be that when you have to shoot an f/1.1 lens in ultra-low light conditions, you pick your poison. You’re playing the limits.

N.B. All pictures shot in b/w are shot with a new Leica Monochrom (typ 246). All shots in color are with an M (typ 240). It’s absurd to change color pictures to monochrome to try to judge sharpness.

What is it? The MS-Sonnetar is the second modern revival of the 50mm f/1.5 Carl Zeiss Sonnar (West Germany, 1950s-1960s), the first one being the Zeiss ZM C-Sonnar 1.5/50mm. Why this type of lens is popular today is puzzling; when lens coatings enabled highly corrected 50mm lenses like the Planar, all of the expensive cemented groups of the f/1.5 Sonnar became obsolete. Today, the popularity of the Sonnar pattern might be in its imperfection: focus falloff in the form of field curvature and vignetting. The Sonnar yields marginally smaller and lighter overall packaging than a Planar or Double Guass, and it has slightly higher resistance to flare.

Every Sonnar revival/clone/ripoff over the past 50+ years has had its own set of strengths and weaknesses; it seems that almost none of them shows the balanced performance of the original Zeiss design. They either sacrifice sharpness for bokeh or go gaga for bokeh and live with a lot of focus shift.

The Sonnetar goes for the gusto with fewer elements and only one cemented group; a lighter, more compact barrel; and almost an entire stop of extra speed. It is the fastest Sonnar-style production lens in terms of T-stops, edging out the 50/1.1 Zunow by virtue of having fewer elements and more effective coatings.

Getting a handle on it. The Sonnetar is a very compact lens; the barrel is smaller than a 50mm Summicron, flaring out to a wider front section that takes 52mm filters (and no, full-sized B+Ws do not vignette). It’s hard to say whether it is modeled after a Zunow, a 50/1.1 Nikkor, or an Opton Sonnar. But all of them have a particular shape to them. The Sonnetar looks most like the Zunow, with the focusing and aperture rings reversed.

The frontmost ring is focus (supplemented with a small lever in the back if that’s what you want); the rearward ring is the aperture control, which smoothly adjusts from f/1.1 to f/16. Like a lot of older lenses, as the aperture numbers get higher, they get closer together (it is probably also a side effect of the Sonnetar’s super-nifty, perfectly circular German iris. But no matter in splitting hairs between f/11 and 16; you won’t be shooting there anyway.

The tough part of the ergonomics is something you’d never expect: the rear lens cap. It screws into the rear lens group, which unfortunately is also the thing that is the coma control. As for the front cap (which also screws in), you’ll probably leave that in the box with the hand-drawn spherical aberration measurements and the pretty hood. You’ll either use an MRC filter or a pinch cap to keep your fingers off the front glass.

Overall build quality. Done out in matte black chrome, the finish of the Sonnetar is a good match for a black Leica M-P or Monochrom typ 246. The black anodized finish is very tough, and the mounting ridges that you grasp to mount the lens will take bits of skin along with them. Numbers are clearly engraved and filled in white. They are legible and inoffensive. There is no way to 6-bit code this lens, since the rear flange is integral with the lens barrel (it is very much built like an old rangefinder lens with a rotating optical unit).

The glass (modified Sonnar design, more air-spaced) is perfectly clean and perfectly coated (from what I understand, MS Optical’s multicoating is a simple 2-layer). The reality is that the efficiency of modern coatings and the low element count makes internal flare a non-issue. Interior blacking is actually dark grey, which may seem puzzling, but if it’s good enough for telescopes, it’s probably good enough for camera lenses.

There are some build quality nits. One is that the lens (both on the sensor and in the rangefinder) hits infinity with about a mm of travel left in the focusing ring. This is probably an artifact of having that ring be the same part that provides the rangefinder cam. This might be of concern if you are trying to focus at infinity by feeling for a stop – and it is no different a problem than using an Asian LTM adapter that is a fraction of a millimeter too thin. It almost seems like you could just loosen the focusing ring screws and shift it so that infinity was on the stop

The other is that MS-Optical only uses a couple of actual lens mounts. The 51.6mm lens mount provides cam action that approximates a 51.6mm (Leica-spec) lens. Its frameline selection is determined by whether the mount is compressed around a notch in one of the bayonets or not. This lens uses about 90 degrees to go from 1m to ∞, which is quite short. This gives you a much faster acquisition time for focus but degrades the focus accuracy. Contrast this to 1950s and 1960s LTM lenses (and indeed the 75 Summilux), whose ponderously slow focusing rate can cause you to miss the moment completely. In any case, you are much better off using the ring than the lever because the larger diameter of the barrel provides better precision (because it takes more movement of the control surface per unit of focus change).

The $&@(!#% “coma adjuster.” The most famous feature of this lens is a “coma adjuster,” a ring around the rear element that has a white indicator dot and four distance dots (1m – white; 2m – white, 4m – red, and infinity-white). The lens is sold with an instruction sheet that tells you this is for adjusting “coma,” which would be the shape of point light sources (round or not). Why does anyone care about coma? It’s a big deal for telescopes, and that’s what Miyazaki designed for most of his life. What you get in terms of optical performance in the near range is a set of very subtle changes. Perhaps this operates better at a distance, but for its stated purpose, the adjuster seems a little bit gimmicky.

What is not so subtle is that the same control – determining the position of the rear lens group – has a tremendous effect on focus (because it changes the focal length of the lens) and on field curvature (whether the plane of focus is flat across the field or curved inward at the edges). This almost off-label use is actually very easy to exploit (see the discussion of what the directions actually say below).

Focal length control is very important on a super-speed lens. A Leica rangefinder assumes the same movement as a 51.6mm lens. Nominal “50mm” lenses that have a 51.6mm focal length can rely on simple movement of the lens cell when focusing to track from near to far at the correct rate. Shorter lenses (like 35mm lenses) have to translate a smaller amount of lens cell movement (front to back) to a relatively larger amount of rangefinder cam movement. Likewise, a 90mm lens needs the cell to move more than the cam moves. With most 50mm f/2 lenses, variances of a couple of 1/10s of a millimeter in actual focal length are not of great consequence because the lens has a little depth of field (or “fudge factor”). Lenses that have super-thin depth of field, such as an f/1.1 lens, require far more precision in their focal length to work well with a rangefinder. One can also surmise that the coma adjuster ring also serves as a calibration method for the lens that does not require reassembly.

According to the directions, this is how to use the coma adjuster ring:

Adjacent to the coma adjustment ring, you will find a white reference point (see the above illustration) to which an appropriate ring position has to be matched by rotating the ring. Using the coma adjustment system, a very high level tuning/focusing optimisation is made possible.

[…]

For Leica M Type Rangefinder Camera Users Initially, bring the red dot of the ring to the white reference point by rotating the coma adjustment ring. As you familiarise yourself to this lens, you may wish to change the ring position either to the left or right. For example, at the infinity best point, the actual focus point will be slightly brought forward (therefore, take a photo with focus point slightly backward). At the white dot that is best for 2m distance, a focus point will be slightly brought backward (therefore, take a photo with focus point slightly forward). This might take some practice and experience to achieve best results.

In real life, the tips for using this are:

  • Turning the adjuster toward longer distances will make the lens focus closer to the camera.
  • Turning the adjuster toward shorter distances will make the lens focus farther from the camera.
  • Putting the coma adjuster on 1m will cause a back focus of 15-20cm at 1m, which is not insignificant.
  • Putting the coma adjuster on ∞ will cause the lens not to focus (optically) to infinity.
  • Putting the adjuster about 2mm short of the 4m mark will produce best focus at f/1.1-1.6 from just under 1m to infinity. This is not surprising, since it is a distance of about 50 focal lengths (2.5m), which is a conventional distance at which lenses are tested. It is also apparently the setting used to measure MTF (as shown on the instruction sheet).
  • The lens will decouple from an M rangefinder at the minimum distance stop, so don’t do any testing below about 0.8m.

IN MOST CASES, YOU WILL ONLY BE MOVING THIS ADJUSTER 1 or 2MM FROM THE RED MARK. UNLESS YOU WANT TO GO CRAZY.

It really, really, really helps to have a LensAlign to calibrate the lens because you can see the zone of focus very correctly. Although you can trial-and-err it without this $80 plastic device, the problem is ascertaining the effect of focus shift. You want to hit a calibration where the zone of focus includes the intended point through as many apertures as you can – because like a lot of lenses in this speed class, the Sonnetar has under corrected spherical aberration that causes focus shift with aperture changes. The LensAlign lets you observe a band of high contrast as it moves (and expands) as you stop down. You don’t even need to shoot it head-on as you would with a DSLR; you need to check this from oblique angles too – because that is how you will focus your Leica in real life. Needless to say, if you are going to use this lens with a film camera, it helps to have a digital to get it dialed in.

Even within any calibration, the M viewfinder system (including the improved rangefinders for the M typ 240 and 246) has enough lash in it that the direction from which you focus – as well as small movements that don’t even produce a visible change in the RF alignment – can affect the focus point. So the word is “practice.” Wide-open, you will nudge to a slightly farther focused distance (without making the RF spot move).

Performance. All high-speed 50mm lenses (f>1.4) involve tradeoffs. The simple answer is that the Sonnetar has characteristics that vary depending on the coma adjuster setting, and these correspond pretty closely to the optimization differences in an Opton Sonnar, a 50/1.4 Nikkor LTM lens, and a 50/1.5 Canon LTM lens.

For most testing, I have kept the lens optimized at f/1.1 to 1/6 at distances up to 3m. It performs very well from 0.8 to 10m at f/1.1-1.6. If you get the calibration just right, you can keep it sharp through f/5.6, and it’s sharp across the field. At long distances, however, you get progressive blur toward the frame edges. This is gone at f/8. I suspect that the coma adjuster could overcome things, but distance shots are a little outside the use case for this lens (for distance, you are always better off with a slightly smaller aperture lens).

Sharpness seems to max out at f/1.6 (the dot between f/1.4 and f/2 on the focusing scale). Contrast is about double that at f/1.1. If something like the Canon 50mm f/1.2 LTM lens is your frame of reference, at wide-open settings, the Sonnetar is visibly better (and focuses far more accurately). If you are shooting at f/4 or smaller, something like the Canon provides much more balanced performance.

Here is a sequence that should show the differences at the wide apertures. If you click on the picture, you should be able to see it full-size. First, 0.8m, whole scene. Yes, the 44-year-old unopened bottle of Beam is real, as is the gaffe of keeping champagne at other than depressed temperatures. And no, I can’t explain the presence of the CFL bulb on the bar, since I own no fixture that takes them.

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Next, check out the difference between f/1.1 (left) and f/1.6 (right) at 100%. The apertures shown in the metadata are computed by the M typ 246, so they are not entirely accurate. There is quite a bit of contrast jump in one stop.

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Next, here is the same comparison at 200%. The focus point here is the stamp “Spring 1963.”

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Next, here is the mid-right side at 100%. Still holding together.

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Extreme left, 100%. Same story.

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Real-world, stressed out, trying to get enough distance to focus in almost complete darkness, you still get good results. This is f/1.6 at ISO 2500 and 1/12 of a second:

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And a bit better at 1/45 sec (by the way, the Last Word is something you ought to try sometime):

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And this is the obligatory f/8 shot outdoors with a G filter.

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Flare is very well controlled except in extreme side-lighting, where you can get some bizarre effects. This is a characteristic of Sonnar-type lenses. There is some “glow,” which is the normal Sonnar flare on hard dark/light interfaces that occurs when the focus point is ahead of the object. It is more visible in the preview mode of an M camera than it is in the final files. Resistance to extreme backlighting is pretty good, a lot better than with the old Canon 50/1.2:

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Here is the difficult-to-replicate total flare failure mode. You might want to use a lens hood when the sun is in the corner. Or maybe not.

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Vignetting is not going to be a huge issue at close distances, since the barrel is extended. At f/2 and down, it is not obnoxious, especially when combined with the automatic corner correction on the M8/9/240/246. If you want to go very heavy duty on perfect corrections, use the Adobe Flat Field plugin for Lightroom. You will need to shoot baseline calibrations at the distances and apertures you normally shoot. You can do that after the fact.

Color rendition can be a little weird. The “tantalum” glass in this lens (probably standing in for less-exciting sounding “rare earth”) shows mild versions of the color enhancing effects of a didymium enhancing filter (like a B+W 491, Tiffen Enhancing Filter, or Hoya Redhancer). Magenta and yellow seem to be favored here. Here are some pictures that should illustrate this. For your evaluation of secondary characteristics, this is at f/2:

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f/4:

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f/1.1:

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f/1.1:

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Chromatic aberration is a factor here but not in the traditional way. Wide-open, this lens tends to have the blur from adjoining colors bleed together. On an M typ 240, this looks a little bit like soft focus. On the M typ 246, this disappears completely, and the lens develops some killer contrast. This is characteristic of sticking a lot of old-school lenses on the new Monochrom body; a lot of older optical designs suddenly start looking awesome.

Bokeh is such a bourgeois concept. With spherical lenses, you either get universally good bokeh but bad focus shift (ZM C-Sonnar) or poor bokeh and reduced focus shift (50/1.4 Nikkor, 50/1.5 Canon). Unfortunately, with high-speed lenses, the latter combination (or in this case calibration) is much easier to live with. With the Sonnetar, you want to get as close to your subject as possible with as great a distance from it to the background as possible. Otherwise, you can enjoy what generation of Canon and Nikon Sonnar clones have experienced. By the way, here is a direct comparison between the bokeh of the 50/1.2 Canon and the Sonnetar. Maybe you can tell which is which?

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Conclusion. If I did not currently own eleven 50mm lenses (just temporarily), I don’t know how I would feel about this one. That said, the Sonnetar is the one that seems to be welded onto my Monochrom. It’s quirky, it takes a lot of practice to use, and even after a couple of months of practice, there is still a lot to master. That said, it’s an elegant alternative to the Coke cans and second mortgages that tend to dominate the super-speed 50mm space.