Leica Summilux-M 50mm f/1.4 ASPH


Last updated March 24, 2012

The Leica description for this lens

A masterpiece: The best 50mm f/1.4 ever

A combination of the know-how of Leica's engineers and the latest developments in manufacturing technology has resulted in this outstanding standard lens. It delivers high-contrast images, with high-resolution detail, even at its widest aperture, and down to its minimum focusing distance. This is made possible by a number of factors including the use of a floating element, special glass types with unique refraction properties, and elements with aspherical surfaces. The properties of this lens not only make it ideal for any photo situation demanding a handy all-rounder with the natural image angle of the 50 mm standard focal length, but also for available light situations, selective-focus shots, and even fine art photography - usually the preserve of much larger formats. Its wide-ranging versatility also makes it a top choice in assembling a Leica M lens outfit.

Important specifications

Focal length 50 mm
M8 equivalent 67 mm
Aperture range 1.4 - 16 (1/2 steps)
Aperture blades 9
Focusing range 0.7 m – infinity
No. of elements/groups 8/5
Angular field, diag./horiz./vert. 47/40/27 º
Filter M 46 x 0.75
Dimensions ø 54 mm, length 53 mm
Weight 335 g
Produced 2004-Current

Performance Data

The following graphs were gleaned from the Leica-provided datasheet (PDF) for this lens:


A full review of the Leica Summilux-M 50mm f/1.4 ASPH lens, including specifications, performance charts, overview, sharpness and vignetting tests as well as sample images and links for further research. If your native language is Russian, our colleagues at the Leica Russia Blog have posted a translated review for your reading pleasure!

Depending on who you ask, the Leica Summilux-M 50mm f/1.4 ASPH lens is often described as "the best 50mm lens in the world" (Leica even makes that claim outright). Of course, the "best" of anything really depends on your definition of same... However, when looking at this lens from a technical, optical and mechanical standpoint - you'd be hard-pressed to counter a statement such as that, as it ticks off just about every technological checkbox available in modern lens design. Without question, it belongs to a very exclusive group at the top of the heap. We're going to review it anyway and explain why this is so.

The Leica Summilux-M 50mm f/1.4 ASPH lens was introduced in 2004 (ironically the same year that Zeiss introduced their C Sonnar T* 1,5/50 ZM and Planar T* 2/50 ZM lenses) and is a radical update to the previous Summilux 50mm f/1.4 lens. The latter had been one of several 50mm Summilux versions dating back as far as 1961 (or 1959 though not as a Summilux). The optical design remained largely unchanged for 43 years and these lenses are collectively nicknamed the "pre-ASPH" Summiluxes. They pushed the limits of the traditional double-gauss design. While the design works well up to about f/2 (witness the Summicron-M 50mm f/2) it becomes quite strained at f/1.4.

It's worth noting at this point that the pre-ASPH Summilux lenses have their own following - some prefer the older, more "classical" rendering of these lenses as opposed to the more modern and "clinical" look that ASPH lenses bring to the table. Generally they offer a lower contrast image that's sharper in the center and softens slightly towards the periphery. They're "sharp but gentle" in their rendering. This effect, as well as the susceptibility to veiling flare give them what is affectionately called "the Leica glow." It's the differences such as these that will really determine what the "best 50mm lens" is for you - both are excellent lenses - but vary in their technical vs. artistic aspects.

The new ASPH version derives its name by the use of an aspherical element (the fourth one in the middle). Like the latest Summilux-M 35mm f/1.4 ASPH "FLE" this lens has Floating Lens Elements as well, though they're not mentioned as a distinguishing feature since there is no non-FLE ASPH version preceding it. The use of FLE increases optical performance at closer ranges and combats focus shift (something the former Summilux-M 35mm f/1.4 ASPH struggled with) and comprise the last two elements of the lens. There are even APO aspects to its design, though it's not designated as such. With all these changes, a radical departure from the previous double-gauss design is born.

The Lens

The first thing that strikes you when looking at the lens (especially if you're used to fast lenses on SLRs or even other M lenses such as the Voigtländer 35mm f/1.2 Nokton) is its diminutive size. It's quite compact for a lens of its specifications - the diameter is similar to many Leica lenses; only slightly larger than the diameter of the lens mount itself. Like the previous version, it shares the common 46mm filter size and also includes a built-in, slide-out hood (though of a new design) - however, it is slightly longer now. It's especially longer than the Summicron-M 50mm f/2, the next-slowest lens in the Leica range. Consider the following (actual side-by-side) comparison between the Summilux on an M9 - and a Canon EF 50mm f/1.2L USM lens alone (without the huge hood) just for entertainment purposes:

Despite its small size, the weight and feel is surprisingly dense - more so the chrome version than the black - which are 460g and 335g respectively. The reason for this difference is that Leica, unlike other manufacturers, uses different materials for the two versions. The chrome version is comprised of brass underneath whereas the black version utilizes aluminum. The mechanical construction is similar to most Leica lenses and in a word, superb. There are no rattles, no slop in the focus ring and apertures click into place precisely and easily. Indeed, the focus action is very well damped and smooth from lock to lock. The lens can be focused with the ring but the preferred method is via the finger tab which is very fast to use (with some practice) and allows you to pre-focus without looking at the lens. While you can do the latter with Zeiss ZM lenses, you can't do the former. Voigtländer lenses vary widely in their implementation, from finger tabs such as found on the Summilux to small levers.

The lens comes supplied from Leica as do all their lenses; an outer and inner box, manual, registration card and proof certificate. The lens comes with both front and rear caps as well as a padded leather case. Since this lens pre-dates the digital Ms (namely the M8 introduced in 2006) not all are 6-bit coded. Versions produced post-2006 are factory coded however and if yours isn't, can be sent to Leica for coding at a nominal fee.

Focus is as accurate as can be, assuming your body is also within spec. There is no hint of focus shift at any range or aperture - a clear sign that the floating lens elements are working as designed.

There is visible vignetting wide open at f/1.4 but clears up rapidly by f/2, leaving just the very corners at f/2.8 and is gone completely by f/4. When coded for digital use and the camera has Lens Detection set to AUTO, there is still minor vignetting at f/1.4 but f/2 and f/2.8 are markedly improved. There are no signs of odd colorations in the corners, which is more of a wide angle lens issue on both the M8 and M9.

Sharpness is where this lens will surely leave you somewhat in awe - from wide open. This is "where the money went" as it were. Even wide open at f/1.4, the center of the image is surprisingly sharp with a slight falloff into the edges and corners. You can easily, and without worry - shoot this lens at f/1.4 all day long. The sharpness in the center combined with the thin depth of field at this aperture will make your subjects really pop from the background. Stopping down improves performance slightly, especially into the edges and corners but already at f/2 it's sharper than the previous champion, the Summicron-M 50mm f/2. Depth of field increases as does micro-contrast (small detail definition). Stopped down further to f/2.8 and f/4 the performance evens out across the frame and the lens peaks until about f/8 before diffraction starts to affect sharpness and resolution. Perhaps needless to say, at peak apertures - the Summilux delivers rather amazing image quality throughout the entire frame. It stops down to f/16 as with most high-speed lenses (as opposed to f/22 on slower designs).

Distortion is very slight, practically non-existent for all intents and purposes. You'd be hard-pressed to even notice it.

Flare is very well controlled and handling exceptional even wide open. The built-in, slide-out hood is very convenient as it's always handy, impossible to remove or lose yet doesn't add bulk to the lens. As with any lens, its use is highly recommended though even without, this lens performs very well. Some issues have been noted when using filters, and course applies to any lens when used - so if you plan to use one, be it a UV for "protection" or a UV/IR for M8 use, keep this in mind and try to use only the best filters available.

The bokeh is subjective regardless of lens, but the new ASPH version does differ from the pre-ASPH Summiluxes. It's a bit more relaxed and smoother - more diffuse. It's quite pleasing in its own right. As with any lens, background detail and distance as well as camera to subject distance all affect bokeh. Even with a busy background and under the right conditions, details remain smooth rather than jarring or "nervous." Coma is very well controlled as well and round, out of focus highlights near the borders stay round.

Size Comparison

Comparing the Summilux to its main competitors - the Zeiss C Sonnar T* 1,5/50 ZM and Voigtländer 50mm f/1.1 Nokton. While arguably the C Sonnar is meant as a "classic" lens and the Nokton a "super high speed" lens, they are the only currently available new lenses from Leica's two main competitors with similar specifications. The lenses are focused at infinity to represent their shortest possible length.

First, a comparison with no hood attached, or in the case of the Summilux - retracted:

Next, a comparison with the appropriate hood attached - or extended. In the case of the Nokton, the optional vented hood (LH-7) is shown:

As you might imagine, all block some of the viewfinder, even more so when the hood is in position. But because the 50mm framelines in the viewfinder are relatively smaller than say, 35mm or 28mm - impact framing just a little less than first glance might indicate. The C Sonnar has a bayonet mount hood which is quick to install and remove but leaves you with an additional part in-hand. With the Nokton, the optional hood shown above is highly recommended as it will give you additional viewing area through the venting. However, it's even more complicated to install and remove as it consists of the hood and retaining ring which is screwed into the front threads - leaving you with two additional parts in-hand. The Summilux is perhaps the nicest design of the three as it simply slides out and twists slightly to lock in place. Unlike say, the Elmarit-M 90mm f/2.8 lens hood which slides out but does not lock - a minor detail, but offers improved functionality. It is not removable so therefore will not get lost, forgotten nor leave you with any extra parts to carry. Best of all, it adds practically no weight or bulk to the lens, extended or not.

Other Thoughts

The Leica Summilux-M 50mm f/1.4 ASPH lens is really hard to find fault with and thus makes for a somewhat "uninteresting" review. Through the use of modern lens design utilizing "all the tricks" of the trade and exotic materials such as the glass used in the elements, it delivers outstanding image quality from wide open and can thus be used at any aperture and any distance without question or worry. There is practically no distortion, no focus shift, is quite flare resistant and if anything has mild vignetting.

If one were to look for faults, one might take notice at the price tag. Compared to the garden variety 50mm lenses offered by SLR manufacturers, the price is rather breathtaking. When compared amongst M lenses, it's still rather high as far as the competition goes - but relatively "moderate" (even "inexpensive") by current Leica standards. Witness the latest Summilux-M 35mm f/1.4 ASPH "FLE" lens - which is a thousand dollars more (list price, more on the street). The only 50mm lens more expensive is Leica's own Noctilux-M 50mm f/0.95 ASPH - which is more than double the cost of this lens - for just over a stop more in speed. The Summicron-M 50mm f/2 by comparison is about half the cost and a stop less in speed. The moral of the story? Speed costs! Not just the money aspect, but size and weight also take a dramatic turn. Among the three lenses, the Summicron, Summilux and Noctilux - the Summilux fits in the middle of the range very nicely and much as you'd expect. A reasonable compromise between cost, size and weight. Performance-wise they're all of extremely high caliber - in the end it really comes down to "how fast do you want to go?"

If you shoot an M8 with its 1.33x crop factor, not just the Summilux - but any 50mm lens as your "standard" lens might feel a bit long. This is because the field of view is more akin to a 67mm lens. Therefore, you might want to seriously consider a 35mm lens instead. Just throwing that out there.

Is the Summilux-M 50mm f/1.4 ASPH worth the money then, in the grand scheme of things? There are very few third-party lenses that compare in terms of mechanical construction, feel and refinement. While other manufacturers compare to varying degrees, this is as good as it gets. Optically, there's really not very much to say either as it's also state of the art. Compared solely by similar speed, neither the current Zeiss C Sonnar T* 1,5/50 ZM nor the Voigtländer 50mm f/1.1 Nokton compare wide open. The smaller Sonnar starts to compete well stopped down but has a more "classic" character towards wide open where it has a focus shift. The Nokton performs reasonably well from wide open and especially stopped down but suffers from focus shift as well. It's also rather large and heavy. When it comes to build and wide open performance at (or near) f/1.4 - the Summilux is where it's at and what you're paying for and no other manufacturer compares with their currently available lens offerings. You'd have to look at vintage lenses for the former and give up the latter.

At a slightly slower speed, the field opens up dramatically and wide open performance across the board tends to improve as well. The Voigtländer 50mm f/1.5 Nokton Aspherical (LTM) compares more to the prior version Summilux in terms of performance and is a much-loved lens, especially among B&W shooters. Slower yet the Zeiss Planar T* 2/50 ZM compares more to the Leica Summicron-M 50mm f/2. With a slightly wider focal length you get the Voigtländer 40mm f/1.4 Nokton which is remarkably small and inexpensive, with decent wide open performance though with a fair bit of distortion and sometimes questionable bokeh. Either the Planar or Summicron would likely serve best and are excellent from wide open and just get better stopped down. Similar optical performance but a reasonable set of price points depending on your budget and preference.

Okay, so is it "the best 50mm in the world?" Yes - and no. From a technical standpoint, more than likely, yes - or awfully close. From a more emotional, artistic standpoint perhaps not. Not that it doesn't have character... But not like a vintage Sonnar design for example. The ASPH lens also has rather high contrast - something not always welcome when shooting film such as with black and white or slide or even digital cameras that have a narrower dynamic range. As with any focal length lens, but especially for this quintessential standard - one could argue having multiple 50mm lenses...

If you truly wanted to buy only one lens for your camera, this (or the slightly wider Summilux-M 35mm f/1.4 ASPH FLE) would make ideal candidates for modern, carefree, high-quality mechanical and optical performance when nothing less will do.


Vignetting was tested using the M9 at ISO 160, firmware version 1.176:

Lens detection set to OFF






Lens coded as a Summilux 50mm f/1,4 ASPH (11891) and lens detection set to AUTO








This test is preliminary, and only tests the center performance - but it should give you an idea of what to expect. It was conducted by shooting a test target at one meter (1m). Images were shot at the various apertures with an M9, mounted on a tripod with a cable release. Wide open shot at f/1.4 was focus-bracketed using three shots. No alterations were done to the image except for auto level and they are 100% crops:

f/1.4 f/2 f/2.8 f/4 f/5.6

Just for the sake of comparison and to provide a sense of how sharp this lens actually is, consider the following four images. They are all shot at f/2 on the M9 and come from other lens reviews done in the same way. The first lens is the Zeiss Planar T* 2/50 ZM, followed by the Voigtländer 50mm f/1.1 Nokton, Leica Summilux-M 50mm f/1.4 ASPH and finally, the Noctilux-M 50mm f/0.95 ASPH. Ignore any white balance or brightness differences and rather take note of the contrast and sharpness between black and white, especially in the fine details. The color móiré you're seeing in the Summilux and Noctilux shots is an indication that the lens is outresolving the sensor.





Sample Images

Flickr Pool Images

Further Research

Sample images thread in forum
Leica Summilux 50/1.4 ASPH group on Flickr