For many photographers and photographic artists the World over a 50mm prime lens is often the most important lens they own. Not only is this a focal length of great importance to photographers, it's perhaps of even greater importance to lens manufactures, often being the pinnacle lens of their lineups. In my opinion this could not be more true of Leica and their now legendary 50mm f2 Summicron for rangefinder cameras. This is a lens that for nearly 75 years has been the benchmark by which all other 50mm lenses are compared. Just the mention of the name Summicron brings with it the implication of an outstanding lens with few if any flaws. The Summicron lens line is often considered to be Leica's attempt at optical perfection. The line started life in 1953 with a collapsible LTM mount Summicron 50mm f2 lens. This was the start of one of the most storied camera lenses in history.
When I started my explorations of the Leica M system a few years ago I went through a myriad of different 50mm lenses from several manufacturers, all of them were good in many ways, but none of them were exactly what I was looking for. So did the 50mm Summicron buck that trend? Let's find out!
The 50mm Summicron for rangefinder cameras has gone through at least 6 iterations that I am aware of, excluding any special additions. Starting from the above mentioned LTM lens up to the current top of the line APO Summicron-M 50mm f/2 Asph. Whilst the latest version is considered by many to be the World's finest 50mm optic, the version we looking at in this article is the 5th version and last of the pre-aspherical designs. We will call this the 50 Cron V5 for ease of reference. The V5's optical design dates back to 1978, and was introduced in the earlier 'Version 4'. The main differences found on Version 4 is that it has focus tab and a detachable hood. It has also become rather expensive in the 2nd hand market due to the preference by many photographers for a focus tab over a focus ring. I was fortunate to have had the opportunity to try both versions before I bought my V5 and found that for me I preferred the focus ring design. I think this may be because I enjoy taking my time with composition, focus and exposure and the focus ring feels more precise. The built in retractable hood of the V5 is also more practical. For photographers who want fast focus the V4 might be your calling.
Leica lenses are well known for a number of things. One being their outstanding optical performance in most cases, their beautiful build quality and lastly (and rather controversially) their often exorbitant price tags. The V5 is not a cheap lens at $2800 USD brand new, and maybe only a few hundred dollars less for a good 2nd hand copy but it does still represent one of the more attainable entry points into Leica branded lenses. This point should outline just how well Leica lenses retain their value. This is also the reason I tell people that if they are curious about Leica they should simply go buy an M3 & 50mm Cron or M2 and 35mm Cron depending on preference for focal length. If they love it, it will eventually go up in value whilst providing many years of service and if they hate it they can sell it again without losing much if any money at all. Enough said on price, let's take a look at build quality.
The Summicron-M 50mm f/2 is an all metal and glass gem. Very compact, protruding only 43mm from the camera mount and weighing in at a modest 240 grams, there is a brass chrome version that is about 100 grams heavier. On the front of the lens, we find a 39mm filter thread. This is important, 39mm is a common filter size used by many Leica lenses as well as 3rd party M-mount lenses, particularly from companies like Voigtlander. Next is the lens hood, which is built in and telescopes out from the retracted position. It's a really practical feature and I wish more lenses had this. Along the front of the lens you find the knurled aperture ring, which moves very precisely in half stop clicks from the maximum aperture of f/2 to f/16. Moving back we have the focus ring with the same style knurling as the aperture ring. The focus ring has a silky smooth movement and just about the perfect amount of resistance. The focus throw is about 110 degrees from infinity to the closest focus distance of 0.65 metres, note however that the focus scale only has markings to 0.7 metres which is also the closest distance most M-Mount rangefinders will focus down to. The front half of the lens moves forward as you focus closer. The focus distance is marked on the ring in both feet and meters, so photographers using both imperial and metric systems should feel at home using the painted focus scales. The Depth of field scale is logically placed directly behind the focus scale and is labelled from f/2 to the lens's smallest aperture of f/16. A little red ball protrudes from the rear of the barrel which assists with proper alignment when mounting the lens as do two knurled pads for your thumb and forefinger to hold onto when mounting or removing the lens from the camera. These small details really add to the overall practicality of the Cron. At the back of the lens we find the legendary M-Mount dating back to 1954. The mount has Leica’s 6-Bit coding included which allows Leica digital cameras to identify the lens that has been mounted and apply vignetting and distortion corrections when needed as well as record the mounted lens in the file EXIF data. Once mounted the diminutive dimensions allow for almost zero finder blockage on M cameras even at the closest focus distance with the hood extended. The only negative I can think of in terms of build quality is the lens cap, which is made of plastic and tends to fall off quite easily.
In the World of Leica it is not enough for a lens to be well built, ergonomically excellent and compact. In the end of the day it still needs to perform... and performance is something this lens offers in spades!
The optical formula is a conventional double gauss containing 6 elements in 4 groups. The diaphragm consists of 8 aperture blades which as mentioned above move in half stop clicks from wide open to f/16. Whilst it's outright resolution does not perhaps reach the stratospheric levels of it's newer APO sibling I can say with confidence that it can still stand comfortably along side many of the best 50mm lenses in the World today, such has been the enduring brilliance of the Summicron! It is VERY sharp from it's maximum aperture of f/2 in the centre. The corners are not bad but are raised to excellent levels as one stops down, with centre sharpness peaking somewhere between f/4 to f/5.6 and the corners looking their best at f/8. From there, f/11 and f/16 do start to eat away slightly at the resolution due to diffraction but the lens is still very much useable at these settings.
In terms of distortion the 50mm Cron V5 is about as perfect as any lens I have ever encountered. With a figure of about 0.5% barrel distortion, straight lines in images are rendered exactly so. This is good news for those of us who like making architectural images, particularly on film cameras as no correction to distortion is needed for this lens. Vignetting is evident wide open, I find this appealing but if needed it is easily rectified via in camera corrections of digital Leica cameras, or in post production.
Bokeh is something many photographers are interested in. Particularly dedicated portrait shooters. Keeping in mind that bokeh is rather subjective I won't offer too much comment here, save to say I think the bokeh is lovely and smooth in most cases. However it's not an element of optical performance that is greatly important to me. Alas if one is looking for a dedicated 50mm portrait lens the 50mm Cron V5 may not be the best choice, whilst it certainly can make nice portraits there are less expensive lenses out there that probably do this job better.
Most of my photography is done in black and white and this lens is very well suited to that however colour images are wonderful too. The 50 Cron V5's colour rendering is lifelike and rather elegant, with a neutral to slightly warm signature. The colour is not overly punchy but with very nice separation and tonality in the midtones. Contrast is strong but not excessively so, leaving room for adjustment either way in post production. This is a good thing, as adding contrast either in digital or a darkroom workflow is fairly straightforward, but reducing contrast can be problematic.
Chromatic aberrations are generally very well controlled. They may just be visible at the maximum aperture of f/2 but subside quickly as as you stop down. On digital the little color fringing that is present is easily corrected in post production and on film I can’t say I’ve ever noticed it at all.
The 50 Cron V5 has 2 weaknesses that I do think need to be addressed. The first is a mild focus shift. This is a phenomena that causes the point of focus to move as the lens is stopped down. It is only really a factor when working at close range, particularly closer than 1.5 metres. Whilst I do see this happen in testing, in real world shooting scenarios I have never found it to be a problem. But again portrait shooters working in close range will want to be aware of it if they intend to shoot stopped down a bit. Wide open it’s not a problem provided one has a well calibrated rangefinder. If the 50 Cron V5 is being used on digital bodies there are easy and effective work arounds to correct for the focus shift. On an M body an EVF can be added, or the lens can be used on one of the marvellous SL bodies via the M to L adapter. In these situations you should stop down to your working aperture of say f4 and then focus with the lens stopped down. This both corrects the focus shift issue and coaxes a very high level of resolution from the lens.
The second issue is lens flare. The 50 Cron V5 can flare rather horribly when bright point light sources are near or JUST outside the frame edges and corners. When it happens it can be annoying as it casts a veiling flare across the frame, reducing contrast. In real world shooting I don’t often come across this problem but be aware of it when shooting in challenging lighting situations.
It is a relatively short list of 'cons' then. Save for the mild focus shift which can be overcome, lens flare and maybe the plastic lens cap, there is little else to complain about.
At the start of this review I posed the question as to whether or not the 50mm Summicron-M would be my long term choice for this focal length on Leica cameras and I can now answer that with a very confident YES! The Summicron-M 50mm f/2 is a beautiful, refined optic in a compact form factor and with high performance to boot, fitting in perfectly with the Leica ethos. It will consistently produce stunning images in both B&W or colour and with both film and digital cameras. The ergonomics make it a joy to use and when you take it out you can be confident of coming home with photographs. The system commonality is a further benefit, with 39mm filter sizes being used on many of Leica and Voigtlander's most popular lenses. I've owned my copy for over two years now, and it has more or less always been mounted on one of my Leica cameras. Over the same period I have owned and sold many other 50's... but the Cron has stayed. It is the kind of lens that encourages me to go out and make pictures as often as possible, and that might be the highest praise I can offer to any lens!