The only Leica lens I dont regret

Saturday, 17 June 2023 14:17

The Summicron-M 50mm V is easily my most used lens and over the past year I’ve come to appreciate it more and more. Sometimes I need to remind myself that lenses are a balance of compromises, and this Summicron-M 50 feels to fulfil my needs really well. With my painful history of Leica lens purchases, the Summicron 50 was the only lens that actually worked as expected. Although, also not without its issues.

Each Leica lens and camera comes with a quality assurance certificate. One part signed off to denote the product had been meticulously inspected during production, and the second signature of the person that packaged the lens. Of the seven new Leica lenses I wanted to purchase since November 2021, only the Summicron 50mm V and the Steel Rim Summilux 35mm Re-issue were working as expected. The others were either not properly rangefinder calibrated, and/or infinity hard-stops were incorrect, and/or the optical performance was asymmetrical comparing left to right sides of the frame. My Summicron-M 50mm, seen on the right, came new out the box with missing paint at the DOF scale marked with a red circle. 

Some might argue that it flaked off during shipping. The likelihood of this is really low, as no other paint has chipped off in the year of ownership, and my DIY repaint of the surface has held up for this same period too. The lens gets shipped in a cushy padded leather and foam lens case, a significantly more protected environment than how I use the lens.

Mechanically, when one has a good copy, Leica lenses are without a doubt extremely satisfying to use and feel like high quality pieces of craftsmanship. At least the large majority of times, their mechanical build, operational feel and industrial design are just second to none. “...when one has a good copy"

The Summicron-M 50mm is a classic lens in many interpretations of the word, with a strong history dating back to the early 1950’s. The Summicron 50mm has been a staple lens for many Leica M photographers over many years, offering great value, a compact form factor, relatively fast aperture, and great optical performance. The current iteration, better known as version V, is probably eeking out every last drop of performance the double-gauss design has to offer.

Since the version V shares the same optical configuration as the version IV released in 1979, it's still officially classified as Version IV by Leica, no matter if one has the model 11826 (version V) or 11819 (version IV). Since the release of the Version IV in 1979, it’s undoubtably seen minor silent revisions, improvements and optimisations with the aid of modern manufacturing processes and materials. 

The Summicron-M 50mm V has a light and very smooth focus feel. The focus is easy to operate with one finger, but the missing focus tab is a polarising decision. The aperture ring is easy to adjust with lightly dampened clicks, arguably a little too light and loose for some, but I have no complaints here. The built in hood seems nice at first, but it’s not at all practical nor effective. Over the years it will tend to get loose, sloppy and prone to creep as the friction material wears thin. I therefore hardly ever use the hood. Overall, the Summicron-M 50mm V feels solid and extremely well made, providing the user with a confidence it’ll last a lifetime. 

The imaging character of the Summicron-M 50mm V lens is hard to describe. It should probably still be regarded as a high contrast lens with modern coatings, but with slightly subdued or gentler micro and macro contrast. Extremely fine details are well resolved but don’t feel overly sharp, with the biggest difference probably in visual acuity than the ability to resolve very fine detail. Compared to its “contrasty” double-gauss twin, the Zeiss Planar 50mm f/2, the differences are noticable but not huge. 

The Summicron-M 50mm V doesn’t have a strong image signature, and I would best describe it as neutral but not clinical. It does everything quite well, but doesn’t excel at anything specifically. The out of focus rendering is quite good; not harsh but also not buttery smooth. Longitudinal chromatic aberration and spherochromatism is relatively low and well corrected given its older design. Latteral chromatic aberration is extremely low and barely visible. The lens isn't perfect or void of optical flaws, but surprisingly neither was the APO Summicron-M 50mm ASPH for the short time I owned it… The more I use the Summicron-M 50mm V the more I appreciate it.

There are sittuations where the bokeh can come across as fairly smooth and neutral, but other instances where specular highlights and out of focus elements can contain chromatic aberration with some slight bright outlining, which gives it a harsher and busier look. It really depends on the light. After all, it’s not all too difficult to have even the smoothest rendering lenses create unpleasant bokeh. On top of this, bokeh rendering is highly subjective. The term neutral, which is how I would describe the lens rendering, is perhaps its best and worst attribute at the same time.

Below are two examples where the same lens provides two different looks...

At their worst, the background blur discs can take on a shade of magenta, with a bright green outer rim. This is probably from a mix of axial colour and spherochromatism. Just as a reminder, even better corrected lenses can still show ugly blur discs like this. The APO Summicron-M 50mm ASPH I had was surprisingly “colourful” in its background rendering and not much better than my Summicron-M 50mm V.

The obsession with blur quality is an unusual and potentially deep rabbit hole. It’s easy to forget that an image is not made by its blur alone, and one can argue the importance at great lengths, but the temptation to pursue some holy grail is all too easy.  

Distortion is often an overlooked flaw, or attribute of a lens. The Summicron-M 50mm V has extremely little of it, to the point where straight lines are straight enough at the frame edges that no correction is needed. I probably value a lack of distortion much more than the next person, otherwise how else can the lens of the Leica Q, Q2 and Q3 cameras get such continuous high praise when its fixed lens is a distortion monster.

The uncorrected image below shows the Summicron’s lack of distortion quite well.

The lack of distortion and its modest field curvature make the Summicron-M 50mm V a good landscape lens. Unfortunately it’s not a flat field lens, but excellent cross-frame sharpness at infinity focus will be achieved by f/5.6 with a 60MP Leica M11 camera. The Summilux-M 50mm ASPH cannot achieve this at f/5.6 let alone f/8, since it has a rather significant mid-zone dip in resolution. These sort of characteristics are important to consider based on what one wants or needs from a lens.

Since the Summicron is a classical double-gauss design, sans aspherical elements and floating lens groups, so focus shift is a typical optical characteristic the user will have to deal with. Focus shift together with field curvature can both contribute to frustration and missed focus. Various Summicron versions I’ve tried all have it. Even lenses touted not to have focus shift, like the Summilux 50mm ASPH and the Summilux 35mm ASPH FLE, have it too but to a much lesser and almost unnoticeable degree. The Summicron 50mm however, needs manual compensation for this. It’s not hard to work around it and get a feel for the degree of focus compensation, but I can relate to the frustration it can cause and the temptation to avoid lenses with focus shift entirely.

My Summicron is calibrated to what looks like f/2.8. Either by intention or happy accident, and I rather like it this way. At f/2 details are still within the slight haze of spherical aberration that doesn’t make the slight front focus obvious. The softer rendering the lens has at f/2 is very forgiving towards a slight front focus, since the detail behind the plane of focus has a smooth transition through the spherical aberration into the background blur. If it were perfectly calibrated for f/2, by the time one stops down to f/2.8 it would become obvious there is a focus shift, which makes a f/2.8 calibration quite the practical compromise. My Summicron does need a slight focus compensation when shooting shooting at f/4 and f/5.6 but it’s easy to learn and compensate with a specific offset of the camera’s rangefinder focus patch. By comparison, the Zeiss ZM Planar 50mm has a similar degree of focus shift and also needs manual compensation for critical focus. The Summilux 50mm ASPH has its focus shift move slightly rearward when stopping down, but at least the subject remains within the focus plane. A lens somewhere in between the Summicron and Summilux would be the Voigtlander Nokton 50mm f/1.5 ASPH II. 

Like focus shift, there are other elements of the Summicron-M 50mm V I dislike. As seen in the image above, veiling flare from light sources well outside the frame can be unpredictable and capable of ruining a shot. This isn’t Leica glow, although, it's a Leica thing. Within the frame, the Summicron handles bright light sources fairly well, but it’s in sittuations where light sources outside the frame make shooting unpredictable. Thank goodness for live view or image playback, but if you're a film shooter then it’s an outright gamble. Another example can be seen below. The left image shows veiling flare from the sun outside the frame, with hood extended, while the image on the right was taken with my hand shading the lens. The built in hood was useless.

Another annoyance I have with the Summicron-M 50mm V is it’s prone to a very slight mechanical vignetting when using some filters. I’ve tried a few different brands, and many of them contribute to vignetting, including the B+W 010 UV Haze F-Pro. These are fairly thin profiled filters, but it would seem the inner aperture is what contributes to the vignetting. Stopping down to f/8, with infinity focus on a uniform sky, the very far corners can feel unusually dark. The image on the right illustrates this. There was no such vignetting without a filter.

I use an older Leica UVa filter housing with replaced glass on my Summicron. This works the best for me. I have no intention on testing a US$ 140 Leica branded filter, so I can’t say how good they work.

It's definitely mechanical vignetting from the filter frame, since I can blank out the filters by removing the glass and the effects are identical. Below is a comparison showing the effects of filters attached to the Summicron-M 50mm V, but with the contrast significantly increased to exaggerate the issue. I will emphasise again, that removing the glass from any of these filters shows the same results. 

The test was done photographing a film light box, with the lens set to infinity focus, aperture at f/5.6, shutter speed set to manual, and the camera’s lens detection switched off.

While the Summicron is one of the cheapest Leica lenses available, it's still a formidable expense for many. To me, Leica as a brand doesn’t offer much in the form of quality, quality control and virtue to justify their excessively high prices. It's therefore not surprising that photographers will seriously consider the Zeiss ZM Planar 50mm f/2 as an alternative to the Summicron-M 50mm. They are after all quite similar; both a Double Gauss design, similar in size and performance but with a 3x price difference. 

There are some subtle differences that are worth mentioning, which may tip the scales in favour of one over the other. The two lens diagrams can be seen below, with the Summicron on the left and the Planar on the right.

One often hears about the biting sharpness and harshness of the Planar 50mm. Yes, compared to the Summicron it's slightly more contrasty with higher micro contrast and acuity. This is more a reflection on the Summicron than the Planar, because putting the Planar up next to the Summilux and suddenly the Planar doesn’t seem too different at all. In fact, I would say the Summilux-M 50mm ASPH has a slightly deeper contrast and richness to the shadows.

I feel the Planar’s reputation is a result of regurgitated and unsubstantiated claims without any testing. 

Below is a high magnification comparison of the Summicron and Planar lenses shot in harsh mid day Namibian sun, with an aperture value of f/4 . Summicron on the left, Planar on the right.  
You may also notice the magnification differences in the two images, which is the result of the two lenses having slightly different focal lengths.

Just for fun, let’s compare the supposedly too-contrasty-for-portraits ZM Planar 50mm with the much loved portrait lens, the Summilux-M 50mm ASPH. Below is a high magnification crop of a high contrast scene. Part of the Summilux’s charm is just how well it renders at its widest apertures, with a clarity and richness that is hard to beat. The Planar is in no way higher in contrast or detail, at least the limit of which I haven’t seen yet on the Leica M11!

For me, the biggest differences between the Summicron and the Planar are with their distortion, focal length, colour aberrations and light transmission.

The Planar has barrel distortion. Not a lot for some, but it’s enough to irritate me. Photographing straight lines will show a bow especially at the corners where the distortion is strongest. 

Another irritant is that the focal length of the Planar is notably wider than the Summicron. My Summicron-M 50mm V has a focal length of 52.2mm according to the markings on the lens barrel. Leica 50mm lenses are often a hair longer than 50mm, with lens markings to indicate the exact focal length. The Planar is noticeably wider, and while I don’t know the exact measured focal length, I’m guessing it’s actually just under 50mm. Exact composition with the Planar falls outside the camera’s frame-lines which leaves a bit of guesswork when it comes to composition. With the Summicron, my M11 is surprisingly accurate with its built in frame-lines. 

The colour fringing of the Planar is similar in many ways to the Summicron, but I feel the colour aberration is often more pronounced in that the colours are firstly more vivid and saturated, but also the hues of the aberration are more distinctive. The aberrations of the Planar are more Cyan and Magenta while the Summicron is a little more green and purple. The Summicron’s aberrations seem to blend better with image and are slightly less distracting. Overall, I would say the differences are very small.

Below is a comparison of bakcground out of focus areas. Note the amount of colour aberration and the difference in colour shades. To me the Planar seems a little more obvious or distracting.

The Planar has better light transmission than the Summicron. The Planar creates a brighter image centre at f/2, and in general shows less light fall-off and overall better light transmission up to around f/4 when the differences become negligible. 

See the image comparison below, where I compare images taken at f/2 and f/2.8 with a diagonal slice showing the Summicron image on the left and Planar image on the right. All exposure, white balance and Lightroom settings were the same. The camera lens detection was set to off and no lens corrections were applied in Lightroom. No filters were used either. 

In conclusion, the Summicron-M 50mm V is an excellent performing classic lens design that embodies real Leica legacy and is a slice of photographic history. As Leica lenses go, it offers great value, but it’s no less still quite expensive with several alternative M mount lenses that provide a better perfromance to value proposition. It's however still a Leica product, and this brings with it a novelty and a luxury tax so to speak. While the quality control at Leica is rather shocking given their reputation, heritage and promise of excellence, their products do have that unmistakable edge over the competition. Notably in haptics and industrial design language. Voigtlander are producing some remarkable lenses, and while some of those optically match or out perform their Leica counterparts, their inconsistent design language and haptics make the Leica products often more desirable even with the significantly higher prices. The competition Voigtlander provides is invaluable and its great at attracting photographers into the M system. 

What I do look forward to is Voigtlander releasing an Ultron 50mm or reissuing a Color-Skopar 50mm f/2.5. One can never own too many 50mm lenses!