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# Summicron vs Summilux vs Noctilux: Which Leica 50mm to Buy
- URL: https://www.unknowndivide.com/summicron-vs-summilux-vs-noctilux/
- Published: 2022-10-02T15:00:00.000Z
- Updated: 2026-11-09T06:47:20.000Z
- Description: Three Leica 50mm lenses, three very different tools. We decode the names, put the official specs side by side and pick the right one for each photographer.
- Author: unknowndivide staff
- Tags: Gear, Tech

Leica names its lenses the way a wine region names its vineyards: the word on the barrel tells an insider almost everything. Summicron, Summilux and Noctilux are three 50mm lenses for the same M mount, and they can look nearly identical in a shop window. In practice they are three very different tools, built for three different kinds of photographer. This guide decodes the names, puts the official Leica numbers side by side and gives a firm pick for each buyer.

## The quick answer

- **Summicron-M 50 f/2:** the one most people should buy. Small, light, sharp and the easiest of the three to live with every day.
- **Summilux-M 50 f/1.4 ASPH:** the one for available light. A full stop faster than the Summicron and still compact enough to leave on the camera.
- **Noctilux-M 50 f/0.95 ASPH:** the one for a look. Heavy, demanding and unlike anything else, built for photographers who want the background to melt.

## What the Leica lens names mean

Here is the part most new Leica owners never get told. The name is a code for the widest aperture. In Leica's M lineup, Summicron means f/2, Summilux means f/1.4 and Noctilux means faster still, around f/1.2 and beyond, all the way to f/0.95\. Further down the scale, Summarit means f/2.4 or f/2.5 and Elmarit means f/2.8\. Once you know that, a Leica catalog reads like a menu.

Noctilux is the only name Leica explains outright. The company says it comes from the Latin words for night and light. The first Noctilux, a 50mm f/1.2 from 1966, used two aspherical elements at a time when shaping glass that way was painstaking work, and Leica calls it a lens that added a new dimension to photographing at night. A 50mm f/1.0 followed in 1976, and the current f/0.95 version was unveiled at the photokina trade fair in Cologne in 2008.

One more piece of shorthand. ASPH, short for aspherical, on the barrel means the design includes at least one lens element whose surface is not a simple slice of a sphere. Aspherical elements let designers correct a fast lens with fewer pieces of glass, which is how the Summilux stays small.

![Leica Summicron-M 50mm f/2 lens in black anodized finish with engraved focus and depth of field scales](https://storage.ghost.io/c/25/41/254117cc-2631-4fb7-9f78-fa31eac12f1a/content/images/2026/11/leica-summicron-m-50-f2.jpg)

Summicron-M 50 f/2\. Image: [Leica Camera](https://leica-camera.com/en-US/photography/lenses/m/summicron-m-50mm-f2-black?ref=unknowndivide.com)

## Summicron vs Summilux vs Noctilux: the spec table

Every figure below comes from Leica's own technical data. We have left prices out on purpose, since they change often. The gap between the three is large, and it grows with every stop of speed.

| Spec                    | Summicron-M 50 f/2                        | Summilux-M 50 f/1.4 ASPH                     | Noctilux-M 50 f/0.95 ASPH                                                      |
| ----------------------- | ----------------------------------------- | -------------------------------------------- | ------------------------------------------------------------------------------ |
| Widest aperture         | f/2                                       | f/1.4                                        | f/0.95                                                                         |
| Optical design          | 6 elements in 4 groups                    | 8 elements in 5 groups, 1 aspherical surface | 8 elements in 5 groups, with aspherical and anomalous partial dispersion glass |
| Rangefinder focus range | 0.7 m to infinity                         | 0.7 m to infinity                            | 1 m to infinity                                                                |
| Filter thread           | 39mm                                      | 46mm                                         | 60mm                                                                           |
| Lens hood               | Built in, pull out                        | Built in, pull out                           | Built in                                                                       |
| Weight                  | About 240g                                | Under 400g                                   | About 700g                                                                     |
| Best at                 | Everyday street, travel, film and digital | Low light, portraits, documentary            | Night, portraits, a signature look                                             |

## Summicron-M 50 f/2: the quiet default

The Summicron is the lens Leica describes as the classic in its purest form, and that is a fair summary. Six elements in four groups, a built in hood you pull out with one hand, a 39mm filter and about 240 grams. On an M body it barely changes the feel of the camera, which is exactly why so many photographers never take it off. Leica says it is assembled from brass and aluminum and calibrated by hand in Wetzlar, Germany.

Leica's own description of how it draws is honest. Wide open it is sharp with a soft, cinematic falloff, and from f/2.8 onward its micro contrast lifts across the whole frame. In plain terms, it is a lens that rewards stopping down slightly and never gets in your way. It is also the friendliest of the three for film shooters, because the short focus throw makes fast zone focusing easy. If you shoot black and white film on an M6 or an MP, read our guide to the [Leica M6](https://www.unknowndivide.com/leica-m6-film-camera-explained/) and pair it with this.

![Optical cross section diagram of the Leica Summilux-M 50mm f/1.4 ASPH lens showing eight elements in five groups](https://storage.ghost.io/c/25/41/254117cc-2631-4fb7-9f78-fa31eac12f1a/content/images/2026/11/leica-summilux-m-50-f14-asph-cross-section.jpg)

Inside the Summilux-M 50 f/1.4 ASPH: eight elements in five groups. Image: [Leica Camera](https://leica-camera.com/en-US/photography/lenses/m/leica-summilux-m-50-f14-asph-black?ref=unknowndivide.com)

## Summilux-M 50 f/1.4 ASPH: the low light workhorse

The Summilux is one full stop faster than the Summicron. That sounds small and is not. A stop doubles the light reaching the film or sensor, which means a shutter speed twice as fast in the same dim bar, or half the sensor sensitivity on a digital body. For people who photograph indoors, at dusk or in rooms where flash would ruin the moment, that one stop is the whole argument.

Leica builds it from eight elements in five groups with a single aspherical element, and the result stays remarkably compact for an f/1.4 lens. It is longer and heavier than the Summicron, still well under 400 grams, and the built in hood keeps the package tidy. The look is clean and precise rather than dreamy. Backgrounds soften gracefully, but subjects stay crisp even wide open, which suits documentary and portrait work. Practice matters here: depth of field at f/1.4 and close range is thin, and rangefinder focusing has to be accurate.

## Noctilux-M 50 f/0.95 ASPH: the statement

The Noctilux is not a faster Summilux. It is a different idea. At f/0.95 it gathers a little more than a full stop more light than the Summilux, and the depth of field becomes so shallow that a face can be sharp at the eyes and soft at the ears. Leica uses floating elements and glass with anomalous partial dispersion to keep it sharp at that aperture, and the company's own phrase for the result is ultra soft bokeh.

The trade offs are physical. It weighs about 700 grams, nearly three Summicrons, and at about 75mm long it blocks part of the rangefinder view on an M body. Close focus stops at 1 meter. Filters are 60mm, so nothing from your other lenses will fit. None of this is a flaw. It is the price of an aperture wider than f/1, and for photographers who want night streets and portraits that look like nothing else, it is the reason to own an M at all. Leica also makes a Noctilux-M 50 f/1.2 ASPH, a modern remake of the 1966 original, for anyone who wants the history with a lighter look.

![Leica Noctilux-M 50mm f/0.95 ASPH lens in black with its large front element and built in hood](https://storage.ghost.io/c/25/41/254117cc-2631-4fb7-9f78-fa31eac12f1a/content/images/2026/11/leica-noctilux-m-50-f095-asph.jpg)

Noctilux-M 50 f/0.95 ASPH. Image: [Leica Camera](https://leica-camera.com/en-US/photography/lenses/m/noctilux-m-50mm-f0-95-asph-black?ref=unknowndivide.com)

## Which Leica 50mm should you buy

- **Your first M lens, or a film shooter:** Summicron. It is light, sharp, simple to focus and holds its value well.
- **You shoot people indoors, at night or in mixed light:** Summilux. The extra stop matters more than any other spec in this table.
- **You want a signature look and accept the weight:** Noctilux f/0.95\. Buy it for the pictures only it can make, not as an everyday lens.
- **You want maximum sharpness at f/2:** look at the APO-Summicron-M 50 f/2 ASPH, Leica's high resolution take on the Summicron idea, before you jump to a faster lens.

If you are still choosing a camera, our explainer on [rangefinder vs SLR](https://www.unknowndivide.com/rangefinder-vs-slr-film-camera/) covers what it is actually like to focus a lens like these, and our guide to [Kodak Tri-X 400](https://www.unknowndivide.com/kodak-tri-x-400-black-and-white-film/) pairs well with any of them.

## Our call

**Our call: buy the Summicron first.** It is the lens that teaches you what a 50mm on an M can do, it never slows you down, and it is the one you will still carry in ten years. Upgrade to the Summilux only when you keep running out of light, and you will know when that happens. Buy the Noctilux when you have a specific picture in your head that the other two cannot make. Skip it as a status purchase, because a heavy lens left at home makes no pictures.

**Shop the Leica 50mm picks**  
**Leica Summicron-M 50 f/2 (black):** the everyday 50 and our top pick for most buyers. [Check price](https://www.amazon.com/dp/B00009V3FL?tag=unknowndivi02-20&ref=unknowndivide.com) or [see it at Leica](https://leica-camera.com/en-US/photography/lenses/m/summicron-m-50mm-f2-black?ref=unknowndivide.com)  
**Leica Summilux-M 50 f/1.4 ASPH (black):** the extra stop for low light, still compact. [Check price](https://www.amazon.com/dp/B00422GVSC?tag=unknowndivi02-20&ref=unknowndivide.com) or [see it at Leica](https://leica-camera.com/en-US/photography/lenses/m/leica-summilux-m-50-f14-asph-black?ref=unknowndivide.com)  
**Leica Noctilux-M 50 f/0.95 ASPH:** the statement lens for night and portraits. [Check price](https://www.amazon.com/dp/B001IKEX68?tag=unknowndivi02-20&ref=unknowndivide.com) or [see it at Leica](https://leica-camera.com/en-US/photography/lenses/m/noctilux-m-50mm-f0-95-asph-black?ref=unknowndivide.com)  
**Leica Noctilux-M 50 f/1.2 ASPH:** the 1966 design brought back, for the history and a gentler look. [Check price](https://www.amazon.com/dp/B08VGW3QJK?tag=unknowndivi02-20&ref=unknowndivide.com)

More like this: browse every related post in our [Leica and Film Photography Hub](https://www.unknowndivide.com/leica-and-film-photography/).

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