Leica Noctilux is a lens, or rather a family of lenses, which is capable of transmitting more light than any lens in the world. To be more exact, at its full aperture of f/0.95 (in case of the previous version, f/1), loss of light is only due to internal reflections from optical surfaces, which is, for practical purposes, is almost negligible. The implication of it is gigantic: Noctilux gives a photographer freedom to shoot in near darkness without a tripod.

Leica M9, Leica Noctilux 1/50 @ f/1, 1/30, ISO1000

What is more amazing, even at f/1 Noctilux delivers image quality sufficient for professional use in photojournalism, editorial and even advertising photography.  The photo above, for example, was taken in the evening, with just two light sources: twilight from the store front, right in the man’s face, and a lamp with a 15W tungsten bulb, which you see in the picture. At 1/30 of a second I managed not only avoid motion blur (which at 1/15 would be very problematic), but make the scene look about two stops brighter than it actually was. This digital image sustained very little post-production (minor color correction compensating for the difference in color temperatures of sources and low sharpening), which literally took less than a minute. The picture, however, can be successfully enlarged for at least an 18x24” print.

In an interest of a full disclosure, I have to mention that other manufacturers, namely Canon and Vöigtlander  also made super-fast lenses in the range of f/0.95 to f/1.1. These optics, however, did not gain much recognition despite their substantially lower prices, for the reason of their inferior image quality. Inferior to Noctilux, that is.

Obviously, image quality at full aperture cannot be expected to match what can a comparatively modest Summicron 50mm f/2 deliver at setting. In fact, no other lens can, because this very 50mm Summicron is a de-facto industry standard normal lens for 35mm photography. The main reason for this disparity lays in serious trade-offs that have to be made in designing super-fast lenses. For instance, in order to control spherical aberrations, the lens must be designed with lower overall contrast. Even use of aspherical optical elements and special glass with anomalous light dispersion characteristics cannot fully address all existing issues. That is why pictures taken with Noctilux at its widest aperture settings, especially when it is done in aggressive lighting conditions (strong hard light, very high contrast, overexposure, contre-jour, point light sources within the field of view), and frequently lack in contrast and sharpness. The most serious drawback of Noctilux is its propensity

Leica M9, Leica Noctilux 1/50 @f/4

to chromatic aberrations when shooting against the light. Even three stops down from f/1 strong backlighting can create purple fringing, yellow/blue and red/green color splits. The image above shows this very problem: a contour of the model’s face looks unsharp, while the rest of her silhouette is sharp. Initially this area was bright purple and remained fuzzy when the color was taken out in post-processing. In this case it worked for the image, while in most cases chromatic aberrations can ruin a shot. 

Having said that, I must acknowledge that the latest version of Noctilux delivers much improved optical performance. At apertures of f/1.4 or smaller, in fact, one will be hard pressed to tell this lens apart from 50/1.4 Summilux ASPH, which was not the case with any of the previous Noctilux incarnations. 

 Leica M9, Leica Noctilux 1/50 @ f/1

One of the most important skills of successfully using Noctilux is an ability to resist a desire to keep the aperture open all the time. Not every shot requires f/1, and often times the strong, almost psychedelic effect that this lens creates at full aperture is detrimental to perceptibility of the image. 

Even with the previous, optically softer version of Noctilux, correct post-processing in Adobe Lightroom (which is provided free of charge with an every Leica M9 body) makes photos taken at f/1 sharp enough to be visually indistinguishable from slower Leica lenses on an 11x14” print.

Incredible light sensitivity is not the only property that makes Noctilux so desirable. With DOF so shallow, the way that the lens renders out-of-focus areas  and transitions between focused and blurred parts of an image, plays an important role. Is easy to understand taking into account the fact that at f/1 rather often only a minor part of an image remains in focus. Hence if the posterior bokeh (this is a fancy name for the blurred background) is harsh and aggressive, the picture is unpleasant for the eye. A significant part of the Noctilux “signature” is its bokeh, which is not as neutral as of 35/2 Summicron ASPH, yet pleasant (see picture below).

 Leica M9, Leica Noctilux 1/50 @f/1

To summarize, understanding when the super-shallow DOF will benefit your subject matter is extremely important.

Also, as I have mentioned previously, this is not an easy lens to use. Overall, shooting with Noctilux is a considerably slower process than with with a lens one or two stops slower. There are several reasons to that:

  • It is heavy and somewhat cumbersome (compared to slower 50mm lenses). 
  • It requires special skills in composing the image regardless of aperture used, just because it obstructs at least 1/4 of the 50mm frame. 
  • Shooting at apertures from f/1 to f/4 requires special attention to the direction of light and overall contrast of the scene.
  • It attracts attention because, even with people who do not know what it actually is, the lens is large enough to look "professional". 
  • At last, its undoubtedly exuberant price may, in some instances, make you overly conscious of the risks, which will negatively influence results of your work.

A question that is probably the most often asked about Noctilux is why one would spend in excess of $10,000 for the luxury of an access to f/0.95, but at a cost of image quality by definition inferior to what a $2000 lens can deliver. Despite its obvious shortcomings, the whole idea of Noctilux, in my opinion, is not excessive at all, at least in professional photography. Even if you look at it from a purely economical position disregarding any aesthetic implications that shooting at apertures wider than f/1.4 may have (although, believe me, they really matter), Noctilux turns out to be well justified when used for what it is intended. When working on assignment, being able to shoot at f/1 (or f/0.95 with the last version) frequently means getting the shot versus not getting it. In professional photography it easily translates into thousands of dollars.