35MM BAYONET MOUNT LENSES

It is important to note that Leica lenses had their focal lengths specified in millimeters from 1925 to 1928, in centimeters from 1928 to 1970, and again in millimeters from 1971 onwards³⁶⁰.

35mm f/3.5 Summaron

General

First version of Leica 35mm f/3.5 Summaron lens was in screw mount only, with A36 filter size and rotating lens mount from 1948³⁶¹. The serial numbers for screw mount version start at 706001³⁶¹.

The bayonet mount version of Leica 35mm f/3.5 Summaron lens was introduced from serial number 1435001³⁶¹. This bayonet mount version came with with E39 filter size³⁶¹. There were 2 versions of Leica 35mm f/3.5 Summaron lens for Leica M cameras: without goggles and with goggles³⁶¹.

There was a special version of this lens with goggles made specifically for Leica M3³⁶¹. Another special version with fixed focus lens was made for the postal services for the Leica MD and Leica MDa Post cameras³⁶¹.

This lens was the first new design introduced after the war³⁶¹. It features a double-Gauss construction and was launched in 1948³⁶¹. While many sources cite 1946 as the earliest date, with serial number 601001, factory records indicate that this batch was actually reserved for the Elmar 3.5/50mm lens³⁶¹.

Later versions of Leica 35mm f/3.5 Summaron lens had had rectilinear movement of the focusing mount³⁶¹. It seems probable that this change occurred together with the introduction of the bayonet mount, as the new Summaron 1:2,8/35mm had this mount too³⁶¹.

The Summaron 3.5/35mm is notably compact and is well-suited for classical screw mount cameras³⁶¹. This design reflects Leitz’s cautious approach, as it operates within self-imposed limits³⁶¹. Although the lens could easily accommodate a maximum aperture of 2.8, it appears that the required types of glass were not available during the design phase³⁶¹. Consequently, Leitz chose to restrict the maximum aperture to 3.5³⁶¹.

The large diameter of both the front and rear lenses helps minimize natural vignetting, and the good color correction is an added benefit, especially for slide film, which was the preferred medium for color photography at that time³⁶¹. The Summaron lens is an excellent performer, rated very highly even by today’s standards, with the best image quality delivered at an aperture of 5.6³⁶¹.

While the Summaron may not be as iconic as the Summicron, it is a reliable workhorse lens, having sold nearly 120,000 units³⁶¹. Although a six-element design may seem excessive for this specification, it’s important to consider that glass research was just beginning at the Leitz glass lab³⁶¹.

Some batches of Leica 35mm f/3.5 Summaron lens have been made in Canada³⁶¹.

Bayonet Mount Version Without Goggles

The version of Leica 35mm f/3.5 Summaron without goggles (11005 / SOONC-M) was introduced in 1954¹⁹⁴.

To properly outline the field of view for the 35mm f/3.5 Summaron lens without goggles, users needed to attach the 35mm bright-line viewfinder (catalog number 12010, code-named SBLOO) to the camera's accessory shoe¹⁹⁴. This required the removal of the coupled Leicameter-M if it was mounted on the camera¹⁹⁴.

Bayonet Mount Version With Goggles

The version of Leica 35mm f/3.5 Summaron with goggles (11007 / SOONC-MW) was introduced in 1956¹⁹⁴. Erwin Puts refers to the lens with ocular attachment for Leica M3 as SOMWO³⁶¹.

Since the M3's rangefinder/viewfinder magnification was 0.91X, which is almost life-size, Leitz found a way to add "goggles" to the 35mm lens¹⁹⁴. When mounted on the camera, this feature minimized the larger 50mm frame to match the 35mm field of view¹⁹⁴. As a result, users could benefit from an integral and easy-to-use 35mm frame without needing to remove the Leicameter-M or carry the comparatively large 35mm bright-line viewfinder separately¹⁹⁴. This rangefinder feature, introduced in 1956, became an instant success, and the resulting 35mm f/3.5 Summaron with goggles gained significant popularity¹⁹⁴.

Interestingly, the 35mm f/3.5 Summaron lenses were designed with removable optical viewing units, allowing for separate storage of the unit, likely in the newly introduced "half moon" leather carrying case (catalog number 14552, code-named ECOOG) for the lens, or in another fashion¹⁹⁴. Some users attempted to use the lens on their M cameras without the optical viewing unit, only to discover that the lens would not focus properly without the "goggles" in place¹⁹⁴. Additionally, removing the goggles would prevent activation of the 35mm frame in the M2 viewfinder, contrary to users' expectations¹⁹⁴.

The removable "goggles" must have posed challenges for Leitz, as this feature was exclusive to the 35mm f/3.5 Summaron lenses and was discontinued for later lenses, which instead featured permanently affixed goggles¹⁹⁴. The early 35mm f/3.5 Summaron lenses had smooth black painted goggles, which were eventually changed to the more durable and familiar black crinkle finish used on all rangefinder lenses thereafter¹⁹⁴.

35mm f/2.8 Summaron

The serial numbers for 35mm f/2.8 Summaron (screw mount and bayonet) ranged from 1615001 through 2312750³⁶¹. There were 6 elements in 4 groups³⁶¹.

The screw mount version of 35mm f/2.8 Summaron (SIMOO/11006) was in catalog from 1958 till 1963³⁶¹. The filter size was E39 and the angle of view was 63 degrees³⁶¹.

The bayonet version of 35mm f/2.8 Summaron was in catalog from 1958 till 1974³⁶¹. There were 2 types of the bayonet version³⁶¹:

without goggles, code-named SIMOM-M, catalog number 11306, minimum distance was 100cm and the weight was 210 grams³⁶¹. The filter size was E39 and the angle of view was 63 degrees³⁶¹.
with goggles, code-named SIMOW, catalog number 11106, minimum distance was 65cm and the weight was 310 grams³⁶¹. The filter size was E39 and the angle of view was 63 degrees³⁶¹.

At the introduction, all three versions of the lens were produced: screw mount, bayonet, and with attachment³⁶¹. A special version featuring a fixed focus lens was created for postal services for the Leica MD Post and Leica MDa Post cameras³⁶¹.

The screw mount lens was available in a lightweight version weighing 135 grams, equipped with a focusing tab and an infinity lock³⁶¹. It also included a Leica M3 spectacle viewfinder with a black finish³⁶¹. Some batches of these lenses were manufactured in Canada³⁶¹.

The first series was produced in Wetzlar, while later series were made both there and in Midland³⁶¹. This Summaron model is closely related to its predecessor in design but provides a slight increase in performance, achieving just over a half stop improvement³⁶¹. This enhancement is attributed to the use of new glass treated with lanthanum³⁶¹.

Unfortunately, the Summaron was overshadowed by the introduction of the new Summicron 2/35mm in the same year³⁶¹. Nevertheless, the Summaron remains a very enjoyable lens to use, especially with digital M cameras, due to its compact design and strong performance³⁶¹. Approximately 52,000 units were produced, indicating its positive reception in the market³⁶¹. At that time, the price of a lens was a significant factor in purchasing decisions, and for many Leica users, an aperture of f/2.8 was sufficient or at least the most affordable option available³⁶¹.

35mm f/2 Summicron-M (version 1)

At its introduction, 35mm f/2 Summicron lens was made both in screw mount and bayonet mount³⁶¹.

Most of these lenses were produced in Canada, while some originated in Wetzlar³⁶¹. They are equipped with a focusing tab³⁶¹. During the same period that the Summaron design by Leitz Wetzlar was introduced, the optical design department at Leitz Midland developed a Summicron lens, which is categorized as an f/2 lens³⁶¹. This lens follows the classical double-Gauss pattern but adds two additional lens elements³⁶¹.

The double-Gauss design can be summarized as follows: a positive (converging) meniscus element is followed by a second meniscus or convex element with a lower refractive index and higher Abbe number³⁶¹. The third element has similar specifications, followed by the stop³⁶¹. The fourth element is a bi-concave element made of flint glass, while the fifth and sixth elements are also made of biconvex flint glass³⁶¹. These rear elements have a higher refractive index than the front elements.³⁶¹

This 8-element design features relatively large front and rear elements, presumably to reduce vignetting³⁶¹. The lens is very compact, demonstrating a good balance between size and image quality³⁶¹. While the performance of the Summicron at maximum aperture is decent, it has lower contrast compared to the Summaron version³⁶¹. However, when stopped down, the image quality is excellent, which is characteristic of most Leica lenses³⁶¹.

During the 1950s and 1960s, lenses with an aperture of f/2 were primarily used by professionals, as they were assumed to work under the most demanding conditions³⁶¹. Although high-speed emulsions were available for black-and-white film, this was not the case for color slide film, making any increase in lens speed highly desirable³⁶¹. Leitz understood precisely how the M-camera would be utilized³⁶¹.

Serial numbers ranged from 1630501 to 2286450 for both screw mount and bayonet mount lenses³⁶¹.

The bayonet mount version came in 2 flavors:

Without goggles:
1. The first version is equipped with an infinity lock and is an 8-element formula¹²⁵
2. engraved Canada or Wetzlar¹²⁵
3. Made with Leica M2 in mind³¹
4. had catalog number 11308 and was code-named SAWOM³⁶¹
5. had catalog number 11307³⁵⁴ for black version
6. Minimum focus distance is 70cm³⁶¹
7. Weight 150 grams³⁶¹
8. Filter size E39³⁶¹

With goggles:
1. Introduced in 1958¹⁹⁴
2. 8-element formula¹⁹⁴
3. black finish with goggles was manufactured in small quantities¹⁹⁴
4. had catalog number 11108 and was code-named SAMWO³⁶¹ for chrome version¹⁹⁴
5. Minimum focus distance is 65cm³⁶¹
6. Weight 225 grams³⁶¹
7. Filter size E39³⁶¹

Bayonet mount version of 35mm f/2 Summicron remained in the catalogue from 1958 to 1974³⁶¹.

35mm f/1.4 Summilux-M - Variation 1 'Steel Rim'

Leitz introduced the 35mm f/1.4 Summilux in 1960³¹ at Photokina³⁵⁹. This first variation, also referred to as "Steel Rim" was wanufactured only by Ernst Leitz Canada³¹.

This compact lens is known for its signature glow and halos. However, the “Steel Rim” is not without its flaws³⁴³. It exhibits softness when used wide open, shows significant chromatic aberrations, creates halos, and produces unpredictable bokeh³⁴³. At full aperture, the overall contrast is rather low, and the definition of fine detail is limited³⁶¹. However, stopping down to medium apertures significantly improves image quality³⁶¹.

This behavior is typical of the era when designers were exploring the limits and possibilities of high-speed lenses³⁶¹. The 1960s were characterized by a frantic quest for extreme high-speed lenses with focal lengths ranging from 35 mm to 90 mm³⁶¹. This search was driven partly by a desire for prestige and partly by the genuine need of photographers experimenting with the boundaries of available-light photography³⁶¹. During that time, the primary emulsion used was of the ISO 400 type, and push processing made it difficult to capture deep shadow details³⁶¹. Under these circumstances, any increase in speed was welcome, even if it resulted in reduced contrast and definition³⁶¹. Photographers were more focused on creating stunning images than on comparing lenses³⁶¹.

There are four types of Variation 1 also known as "Steel Rim":

11869 is the catalog number for black anodized aluminum finish³⁴³ without goggles designed for Leica M2¹⁹⁴. Focusing down to 1 meters²⁰². Came with an infinity lock³⁴². The insides of the lens were brass³⁴³. Lars Netopil interpolated the number of M3 and M2 cameras sold during the period and the estimated the quantities of this type: 80 black lenses without goggles³⁴³. Because the M2 was the accepted camera for wide angle lenses, Lars Netopil suspects that there might actually be around 200 black lenses without goggles, making them very sought after³⁴³. However, one needs to be careful as the last 1000 lenses made were already the re-designed version with A42 front mount, fitting the 12501 clamp-on sunshade - these are much less valuable³⁴³. On the collector market the non-Goggled version is much more appreciated³⁴². Black finish lens was produced in the early batches (serial numbers 1700000) and is also quite rare¹⁹⁴. Production stopped in 1966²⁶³.
11870 is the catalog number for chrome version without goggles designed for Leica M2¹⁹⁴. Focusing down to 1 meters²⁰². Came with an infinity lock³⁴². The insides of the lens were brass³⁴³. Lars Netopil interpolated the number of M3 and M2 cameras sold during the period and the estimated the quantities of this type: 3360 chrome lenses without goggles³⁴³. On the collector market the non-Goggled version is much more appreciated³⁴².
11871 is the catalog number for chrome version with goggles designed for Leica M3¹⁹⁴. Focusing down to 0.65 meters, closer than the Leica M3 rangefinder can normally go, by virtue of a modified cam made possible by the optical viewing unit. Had an infinity catch²⁰². Lower profile "ears" on aperture ring²⁶³. The insides of the lens were brass³⁴³. Lars Netopil interpolated the number of M3 and M2 cameras sold during the period and the estimated the quantities of this type: 4400 chrome lenses with goggles³⁴³. The goggle-eyed Summilux lenses were discontinued by 1974²⁰².
11872 is the catalog number for black anodised aluminium finish³⁴³ with goggles designed for Leica M3¹⁹⁴. Focusing down to 0.65 meters, closer than the Leica M3 rangefinder can normally go, by virtue of a modified cam made possible by the optical viewing unit²⁰². Had an infinity catch²⁰². Lower profile "ears" on aperture ring²⁶³. The insides of the lens were brass³⁴³. Lars Netopil interpolated the number of M3 and M2 cameras sold during the period and the estimated the quantities of this type: 160 black lenses with goggles³⁴³. The goggle-eyed Summilux lenses were discontinued by 1974²⁰². Black finish lens was produced in the early batches (serial numbers 1700000) and is also quite rare¹⁹⁴. Production stopped in 1966²⁶³.

Leitz incorporated rare earth lanthanum glasses for optimum image quality¹⁹⁴. The lens originally came with a push-on/twist-off OLLUX hood, which was later replaced by the more convenient 12504 shade, and it included a screw-in E41 filter²⁰².

At approximately serial number 2930000, the 35mm Summilux received multicoating, which was the first version to show some green reflections alongside the magenta²⁰². This enhancement helped reduce internal reflections caused by light sources within or near the frame and also improved overall contrast²⁰².

This variation had a brief production run, with only 7,500 units made between 1961 and 1966³⁴³. Leitz's shipping records for these lenses do not specify the finish (black or silver) or the mount version (with or without goggles)³⁴³.

The long production period of the Summilux lens highlights the challenges designers face when trying to improve a well-established lens³⁶¹. Particularly daunting are the parameters of an aperture of f/1.4 and a 64-degree angle, which present significant obstacles for designers³⁶¹. It remained in production until 1993 and sold approximately 35,000 units³⁶¹.

35mm f/1.4 Summilux-M - Variation 2

Beginning in 1966, starting with serial number 2166701, this variation featured a simplified lens head and lacked provisions for screw-in filters²⁶³. It is likely that the lens formula was recomputed during this time²⁶³. Series VII filters could be accommodated internally in the 12504 clip-on, divisible lens hood²⁶³. The aperture ring included larger profile "ears" to accommodate the new style hood²⁶³. The lens was supplied with a black anodized finish only and featured a metal focusing tab with a locking infinity catch²⁶³.

35mm f/2 Summicron-M (version 2)

This six-element redesign from Leitz Midland 35mm f/2 Summicron-M (version 2) (catalog number 11309 ) is a very short lens and was created as a more economical version of its predecessor, which featured eight elements³⁶¹. The dual approach of improving performance while reducing production costs was initially successful, but after a brief period, both the optical cell and the mount were changed³⁶¹. The 6 elements¹²⁵ are arranged in 4 groups³⁶¹.

This lens offers somewhat better contrast than its predecessor and exhibits no distortion, a quality appreciated by architectural and landscape photographers³⁶¹. The lens is characterized by good central definition, but it has low contrast in the outer zonal areas³⁶¹. Only 5,000 units of this lens have been manufactured³⁶¹.

The lens was available in the catalog from 1969 to 1973³⁶¹. The serial numbers range from 2307451 to 2318400³⁶¹. The angle of view was 63 degrees³⁶¹. The minimum focusing distance is 70 cm, or 100 cm on the Leica M3³⁶¹. The lens weighs 170 grams and has a filter size of E39³⁶¹. It was offered only in black and features an infinity lock³⁶¹.

The lens uses a "scooped" focusing lever and is fitted with a protruding aperture control lever¹²⁵. The lenses are engraved Canada or Wetzlar¹²⁵.

35mm f/1.4 Summilux-M - Variation 3

The variation 3 of the 35mm f/1.4 Summilux-M lens came only in black anodized mount²⁶³. This variation has a black plastic focusing tab²⁶³. This is the most commonly seen variation of the lens²⁶³.

35mm f/2 Summicron-M (version 3)

In 1973 a third version of 35mm f/2 Summicron-M (catalog number 11309³⁶¹) appeared without the protruding aperture control lever¹²⁵. This lens is also a 6-element formula, according to information available to the writer, although it is probably somewhat different from the second version¹²⁵. There are 4 groups of elements³⁶¹.

The new optical cell, featuring a middle group of lens elements with a larger diameter, effectively reduces vignetting; however, it has introduced some visible distortion³⁶¹. Overall, the differences in image characteristics are minimal and will only be apparent when directly compared³⁶¹. The lens has an additional few millimeters in length, which makes the numbers on the focusing ring easier to read³⁶¹. It is more suited for reportage photography and achieved higher sales, with a total of 21500 units sold³⁶¹.

The lens was in catalog from 1973 till 1979³⁶¹.

The serial numbers range from 2317051 (or 2318251) through 2871600³⁶¹.

The minimum distance is 70cm and 100cm on Leica M3³⁶¹.

The weight is 170 grams and the filter size is E39³⁶¹.

The lenses were engraved Canada and not Wetzlar¹²⁵ and didn't come with infinity lock³⁶¹.

35mm f/2 Summicron-M (version 4)

35mm f/2 Summicron-M (version 4) was introduced in 1979⁸⁸. This fourth Midland version of the 35mm f/2 Summicron-M lens, which features seven elements, produces significantly improved quality at full aperture, particularly in the outer regions of the image³⁶¹. When stopped down to medium apertures (f/4 to f/5.6), it captures fine details with good clarity, and at smaller apertures (f/8 to f/11), exceptional quality can be expected across the entire image area³⁶¹.

Compared to its predecessors, this design is excellent, and its compact size offers notable advantages³⁶¹. However, it is often referred to as the "bokeh champion" among Leica-M lenses³⁶¹. While there is some truth to this reputation, it is important to acknowledge that much of it is shrouded in myth³⁶¹. Leica lenses, especially older or second-hand models, often have special characteristics touted to attract potential buyers, yet in many cases, these traits do not hold up under objective scrutiny³⁶¹.

The optical capabilities of this lens are constrained by the inherent limitations of the double-gauss design used for wide-angle lenses³⁶¹. For the special edition commemorating "1913-1983," three different ranges were allocated, totaling at least 2,500 units—significantly higher than the often cited figure of 800 units³⁶¹. This particular version of the Summicron with the ‘-M’ suffix was a popular choice, with 53000 units allocated and likely sold³⁶¹.

The lens was in the catalog from 1979 till 1996³⁶¹. The black version had catalog number 11310⁸⁸, while the chrome version introduced in 1993 had catalog number 11311³⁶¹. The serial numbers ranged from 2974251 through 3880946³⁶¹. The minimum focusing distance was 70cm³⁶¹. The black version weighs 190 grams (later 160 grams), while chrome version weighs 250 grams³⁶¹. The filter size is E39³⁶¹. The lens was very compact with the new small lens hood³⁶¹. There are 7 elements in 6 groups³⁶¹. The lens features a noticeably enlarged exit pupil due to 7 elements¹²⁵. Also, the lenses were engraved Canada and not Wetzlar¹²⁵.

Special editions

There is a commemorative edition of this lens, engraved "1913 - 1983", to match the Leica M4-P with the same engraving¹²⁵.

35mm f/1.4 Summilux-M ASPHERICAL

35mm f/1.4 Summilux-M ASPHERICAL, also known as "AA" or "Double Aspherical", catalog number 11873³⁵², was introduced in 1989²⁸⁸. Erwin Puts reported that the production of the 35mm f/1.4 Summilux-M ASPHERICAL lens began around 1988³⁶¹. Leitz announced that it would be a special edition in addition to the regular 35mm f/1.4 Summilux, and it was expected to be available in the second quarter of 1990 in a limited run of 2000 units³⁶¹. Although the lens was expensive to produce, its superior performance quickly became well-known, leading to a demand high enough for additional batches, totaling over 4000 units³⁶¹. One author argues that only around 1700²⁸⁸ were ever built due to complex manufacturing process³⁴⁰.

The 35mm f/1.4 Summilux-M ASPHERICAL is generally two stops ahead of the original 35mm f/1.4 Summilux Variation 1 "Steel Rim" from 1961³⁶¹. At an aperture of f/2, it outperforms the older lens at f/5.6³⁶¹. This lens offers very high contrast and excellent definition across all apertures³⁶¹. Its high performance at maximum aperture is ideal for slide film emulsions, producing natural colors with good saturation even in low-light conditions³⁶¹.

Additionally, this lens is renowned for its subtle rendering of depth in images, resulting in photos with excellent three-dimensionality³⁶¹. It has become a sought-after item among collectors, making it quite difficult to find and extremely expensive³⁶¹.

The 35mm f/1.4 Summilux-M ASPHERICAL not only had two aspherical elements, but also a radical new optical design²⁸⁸. Lens has enhanced contrast, exceptional detail resolution, reduced curvature effects, and minimal chromatic aberration and coma due to two aspherical surfaces¹⁵⁰. Two aspherical lens surfaces give the optical system an imaging performance even at full aperture that is unique in compact 35mm lenses¹⁵⁰. Vignetting is nil at full aperture and not visible at f/1.4¹⁵⁰.

The lens features an angle of view of 64° degrees and contains 9 elements¹⁵⁰. Its smallest aperture is f/16, and it has a focusing range extending from infinity down to 0.7 meters.¹⁵⁰ The smallest object field measures 420 x 630 mm, which is approximately a 1:17.5 ratio¹⁵⁰. Included with the lens are a push-on lens hood, lens cap, and rear cover¹⁵⁰. The lens cap has a diameter of 49 mm, while the length from the bayonet flange is 44.5 mm, and the largest diameter is 53 mm¹⁵⁰. The weight of the lens is 0.275 kg¹⁵⁰.

Production ceased in 1994²⁸⁸

The initial list price of the lens was 4050.00 USD¹⁵⁰.

35mm f/1.4 Summilux-M Titanium - Variation 3.1

Introduced in 1992 at Photokina, the 35mm f/1.4 Summilux-M Titanium (catalog number 11860²⁶³) complements the Leica M6 Titanium¹⁶⁹. The list price for the lens was 3150 USD upon introduction¹⁶⁹. The lens was made in small numbers, in brass mount and titanium finish²⁶³.

Technically, this lens belongs in "35mm f/1.4 Summilux-M - Variation 3" category.

35mm f/1.4 Summilux-M ASPH

The 35mm f/1.4 Summilux-M ASPH lens was introduced in 1994 and remained in the catalog until 2009³⁶¹ (or 2010³⁴⁰). This lens had one aspherical element³⁴⁰. The catalog numbers for black, chrome (introduced at Photokina in 1996²⁰³) and titanium versions were 11874, 11883 and 11859 respectively³⁶¹. Serial numbers start at 3636101³⁶¹. The lens features 9 elements in 5 groups³⁶¹. The minimum focusing distance was 70 cm³⁶¹. The weight is approximately 250 grams for the black and 415 gram for the chrome versions³⁶¹. The filter size is E46³⁶¹. This lens has one knurled ring³⁶¹ as opposed to two knurled rings of the 35mm f/1.4 Summilux-M ASPHERICAL, also known as "AA" or "Double Aspherical"³⁶¹. The lens is also slightly shorter by 1.7mm and lighter than the 35mm f/1.4 Summilux-M ASPHERICAL, also known as "AA" or "Double Aspherical"³⁶¹.

The technique of polishing (or grinding) aspherical lens surfaces was quite expensive with the classical machinery available to Leica at the time³⁶¹. Modern Computer Numerical Control (CNC) machinery was not yet developed, leaving the only alternative as the blank-pressing technique pioneered by Zeiss³⁶¹.

Lothar Kölsch, who transitioned from Zeiss to Leica, played a crucial role in introducing blank-pressed lens elements³⁶¹. However, not every type of glass can be used for this process, which required adapting the original design of the 35mm f/1.4 Summilux-M ASPHERICAL, also known as "AA" or "Double Aspherical" lens³⁶¹. The updated lens features one aspherical lens surface made using the blank-pressing method, and it was designated as ASPH. (with a dot)³⁶¹.

Overall, this lens maintains the same optical performance but has a slightly different character compared to the 35mm f/1.4 Summilux-M ASPHERICAL, also known as "AA" or "Double Aspherical"³⁶¹. Mechanically, it is exceptionally well-crafted, with perfect centering of all lens elements³⁶¹.

For more than fifteen years, this lens has set the standard for high-speed wide-angle lenses³⁶¹. One aspect to note is its lower performance in the close-focus range, which has been addressed in newer versions featuring floating elements³⁶¹. However, in most cases, this drop in contrast is not noticeable due to the type of images typically captured with this lens: handheld shots taken with moderately grainy film would make it hard to detect any issues³⁶¹.

The lens is regarded as a reliable workhorse from Leica, consistently delivering excellent results and rarely disappointing³⁶¹.

For the first time, a relatively large lens has been equipped with an aspherical lens surface using the ultra-high precision manufacturing method of press-forming¹⁹⁰. This technology has been in use for some time for mass-produced items with lower precision requirements, such as condensers in slide projectors and illumination lenses for car headlights¹⁹⁰. However, it had only been applied to small lenses until now¹⁹⁰.

The breakthrough was achieved by employing a tool made from a ceramic-like material, which has been diamond-turned multiple times, ground, and polished at specific points¹⁹⁰. Additionally, Leica Camera has developed a special technique for mounting these lenses¹⁹⁰. This method allows the inevitable tolerances in the assembly of the entire lens system to balance each other out¹⁹⁰. Some users say this lens is subject to focus shift³⁴⁰.

The retail price at the introduction was 2695 USD¹⁹⁰.

35mm f/2 Summicron-M ASPH (version 5)

The 35mm f/2 Summicron-M ASPH (version 5) was cataloged in 1996³⁶¹ and introduced in the summer of 1997²⁰⁷. This lens has been developed by Leica engineers to deliver improved performance at all apertures, particularly at the widest settings²⁰⁷. Images captured with this lens will exhibit finer details and virtually no distortion²⁰⁷. Vignetting at full aperture is minimized and nearly disappears from f/4 onwards²⁰⁷. The lens offers a moderately wide angle of view without distortion²⁰⁷.

To achieve a compact design with enhanced image quality, Leitz utilized a molded aspherical surface²⁰⁷. Additionally, this lens features a specially designed protective lens hood to prevent stray light from affecting the image field²⁰⁷.

The 35mm f/2 Summicron-M ASPH (version 5) retains many features of the innovative design for high-speed wide-angle lenses that was first introduced with the original Summilux-M 1.4/35 mm aspherical in 1989³⁶¹. From its maximum aperture to smaller apertures (around f/8), this lens demonstrates high contrast and clarity across most of the image frame³⁶¹.

The 35mm f/2 Summicron-M ASPH (version 5) lens was initially priced at 1645 USD for the black anodized model (catalog number 11879³⁶¹) and 1745 USD for the bright chrome version (catalog number 11882³⁶¹)²⁰⁷.

The titanium version of this lens has a catalog number 11609³⁶¹.

The serial numbers start from 3731291³⁶¹.

There are 7 elements in 5 groups, and one aspherical surface³⁶¹.

The minimum focusing distance is 70cm³⁶¹.

The black anodizel model weighs 255 gram, whereas chrome and titanium versions each weigh 340 grams³⁶¹.

Special Editions

There is a special Special platinum version of this lens made for the limited edition “150 Jahre Optik” (catalog number 10481)³⁶¹.

35mm f/2.5 Summarit-M

35mm f/2.5 Summarit-M (catalog number 11643³⁶¹) was introduced in 2007²⁸⁸. It employs a six-element, four-group construction, but it deviates from the traditional double-Gauss design³⁶¹. With a gap of fifty years separating the Summaron 2.8/35 and the Summarit 2.5/35, there has been a significant advancement in image quality³⁶¹. The lens remains compact, showcasing an innovative optical design that incorporates modern glass elements and effective optimization techniques³⁶¹.

Focusing is incredibly smooth and rapid, requiring only a short throw from infinity to close distance, which allows for quick and precise one-finger focusing³⁶¹. In keeping with Leica's tradition of ensuring a seamless connection between vision and photographic capture, this lens delivers an enjoyable and precise shooting experience³⁶¹.

The Summarit 2.5/35 mm can be regarded as the ideal companion for travelers who appreciate the advantages of a 35 mm focal length³⁶¹. It offers exceptional contrast and definition, and its flare resistance is impressive, partly due to the blackened rear mount³⁶¹.

The angle of view for this lens is 63 degrees and the minimum focusing distance is 80cm³⁶¹. The weight is 220 grams and the filter size is E39³⁶¹.

35mm f/1.4 Summilux-M ASPH FLE I

The 35mm f/1.4 Summilux-M ASPH FLE I, introduced in 2010²⁸⁸, incorporates the floating element technique, enhancing the basic optical design established in the 1989 edition of this classic and popular lens³⁶¹. This technology, where an entire group of lenses moves axially according to the distance setting, was first introduced into the M-line with the 50mm f/1.4 Summilux-M ASPH in 2004³⁶¹.

The main purpose of the floating element technique is to address the loss of contrast that often occurs with stationary lens groups optimized for longer-distance photography³⁶¹. Additionally, the small focus shift present in the previous version (35mm f/1.4 Summilux-M ASPH) has been eliminated³⁶¹.

The 35mm f/1.4 Summilux-M ASPH FLE I is almost the same size as its predecessor (35mm f/1.4 Summilux-M ASPH), but it has doubled in volume compared to the original 1961 35mm f/1.4 Summilux-M - Variation 1 'Steel Rim'³⁶¹. This increase in volume allows for greater geometric flux, meaning more light energy passes through the lens³⁶¹. This reduces vignetting and effectively increases the illumination reaching the sensor surface, although it presents more challenges in optical handling³⁶¹.

One noticeable external change from its predecessor (35mm f/1.4 Summilux-M ASPH) is the replacement of the plastic clip-on lens hood with a sleek metal screw-on version²⁸⁸. This new hood attaches securely in the correct orientation, is more firmly mounted, and takes up less space²⁸⁸. The overall bulk of the lens, including the hood, has been reduced, resulting in less intrusion into the viewfinder²⁸⁸.

35mm f/1.4 Summilux-M ASPH FLE I – Technical Data²⁸⁸
Angle of view	For 35mm format (24 x 36mm): 63°, 54°, 37°, (diagonal, horizontal, vertical)
Optical design	Number of lenses / groups: 9/ 5
	Aspherical surfaces: 1
	Position of entrance pupil: 16.8mm (to the apex of the first lens surface)
Distance settings	Focusing range: 0.7m to infinity
Distance settings	Scales: combined metre / feet gradation
Angle of view	Smallest object field / for 35mm format: approx. 418 x 626mm / 1:17.4
Aperture	Setting / function: With click-stops, half values available
Aperture	Lowest value: 16
Lens mount	Leica M quick-change bayonet with 6-bit bar-coding for digital M models
Filter mount	Inner threading for E46 screw-in filters, non-rotating front element
Lens hood	Detachable (supplied with the lens)
Viewfinder	Camera viewfinder
Finish	Black anodized
Dimensions	Length to bayonet flange: approx. 58 / 46mm (with / without lens hood)
Dimensions	Largest diameter: approx. 56mm
Weight	Approx. 320g

35mm f/2.4 Summarit-M ASPH

redesigned and reintroduced in 2014³⁰²

35mm f/2 Summicron-M ASPH (version 6) 
            
        Introduced in 2016

35mm f/2 APO-Summicron-M ASPH

Introduced in 2021³²⁸
There are 10 elements consisting of³²⁸:
1. 3 Aspherical lens elements (with 4 aspherical surfaces)³²⁸
2. 6 elements using Apochromatic glass³²⁸
3. 3 elements made of glass with a high refractive index³²⁸
Additionally, they have developed a new focusing mount that allows for focusing down to 0.3 meters. To focus between 0.7 and 0.3 meters, you will need to use live view³²⁸.
The lens has a diameter of 53 mm. Without the screw-in lens hood, its length is 40.9 mm; with the lens hood attached, it measures 49 mm. The weight of the lens is 305 grams³²⁸.
By the time the M10 was released, it became possible to manufacture M lenses with closer focusing capabilities. The 35mm APO-Summicron-M f/2 ASPH was the first lens to incorporate this newly designed "double cam" focusing mechanism³⁴⁰.

35mm f/1.4 Summilux-M ASPH FLE II "Close-Focus"

Introduced in 2022³⁴⁰
The 35mm f/1.4 Summilux-M ASPH FLE II 'Close-Focus' lens allows you to focus as close as 0.4 meters. The focusing throw has nearly doubled to 176 degrees, providing a noticeable resistance at the 0.7m mark. Beyond this point, precise focusing requires an electronic viewfinder (EVF), Live View, or the Leica Fotos app³⁴⁰.
Additionally, the new slide-out lens hood is more effective and successfully reduces flare. As a result of these updates, the new lens is approximately 1mm shorter and 1mm thicker than its predecessor, a difference that may not be easily noticeable³⁴⁰.
The 35mm f/1.4 Summilux-M ASPH FLE II 'Close-Focus' features 11 aperture blades. Its optical formula remains the same as that of the 35mm f/1.4 Summilux-M ASPH FLE I. The lens is available in both black and silver anodized versions, and both options weigh the same³⁴⁰.

35mm f/1.4 Summilux-M "Steel Rim" Reissue

Leica announced a 35mm f/1.4 Summilux-M “Steel Rim” Reissue, the remake of the original 35mm Summilux, the 35mm f/1.4 Summilux-M 'Steel Rim' - Variation 1 (catalog number 11870), at the Oskar Barnack Award Ceremony on October 20th, 2022³⁴¹.
This lens is the fourth reissue by Leica, following the reissues of the 28mm f/5.6 Summaron, the 90mm f/2.2 Thambar, and the 50mm f/1.2 Noctilux³⁴³.
The lens is constructed from brass with a silver chrome finish and weighs 200 grams. It comes with two different lens hoods: a remake of the original OLLUX hood and a round screw-in hood. Leica has preserved the 'fall-off' characteristics of the original OLLUX, making the screw-in shade a welcome addition. Unlike the original lens, the new version features a 46mm screw thread for attaching filters. The round hood screws into this thread and retains an internal thread, allowing filters to be attached with either shade or without any shade at all³⁴³.
As with all its reissues, this lens is not an exact replica, as Leica has made adjustments to both the outer and inner mechanics. The outer dimensions differ, meaning that the new OLLUX shade cannot be used with the old models, and vice versa. The 35mm f/1.4 Summilux-M “Steel Rim” reissue also changed from a 41mm to a 46mm filter thread³⁴².
The reissue includes two shades: the OLLUX-styled one and a more traditional threaded round shade that accepts 46mm filters. The lens maintains the brass and satin silver chrome finish of the original but lacks the brass components inside, making the reissue feel lighter at 211 grams compared to the original's 233 grams³⁴².
Leica's optical engineers have replicated the original lens formula, but the coatings have been improved, resulting in a slight difference in image rendering between the original 35mm f/1.4 Summilux-M 'Steel Rim' - Variation 1 (catalog number 11870) and the 35mm f/1.4 Summilux-M “Steel Rim” reissue³⁴².