Pentax

Est. 1919

All Makes

Pentax

Pentax (originally Asahi Optical Co.) is a titan of the SLR world, famous for the Spotmatic and K-mount systems. However, for the Leica M-mount community, the brand is defined by a singular, cult classic "unicorn" lens released during the rangefinder revival of the early 2000s, as well as a hidden history of manufacturing optics for Japanese Leica copies in the 1950s.

While Pentax never produced a native M-mount camera, their limited foray into LTM (Leica Thread Mount) production created one of the most sought after oddities in the ecosystem, the Pentax-L 43mm Special. This lens allows rangefinder users to experience the legendary "SMC" (Super Multi-Coating) contrast and color science that is usually reserved for SLR photographers.

History

Asahi Optical's relationship with the rangefinder format predates their fame as an SLR manufacturer.

Foundations (1919 to 1950s)

The company was founded in November 1919 in Tokyo as Asahi Kogaku Goshi Kaisha, originally manufacturing eyeglass lenses. They began producing camera lenses in the 1930s, eventually adopting the name Asahi Optical Co., Ltd. in 1938. The trademark "Pentax" was acquired later (1957) from East Germany's VEB Zeiss Ikon, but the company's roots in rangefinder optics began well before the "Pentax" name existed.

The "Tower" Connection (1950s)

Before the Asahi Pentax SLR dominated the world, Asahi Optical was primarily a lens supplier. In the 1950s, the Japanese manufacturer Nicca produced high quality copies of the Leica III for the American department store Sears, branded as "Tower" cameras. While many of these were fitted with Nikkor lenses, a significant number were equipped with Asahi Takumar lenses in LTM (M39) mount. These rare vintage lenses represent Asahi's first legitimate entry into the Leica ecosystem [[2]].

The "Special" Project (2000)

In the late 1990s, the rangefinder market saw a massive resurgence due to the release of the Voigtländer Bessa and Konica Hexar RF. Pentax, wishing to demonstrate their optical prowess to this new enthusiast crowd, re-engineered their most famous "Limited" series SLR lens, the 43mm f/1.9, for the Leica screw mount. Released in 2000, the SMC Pentax-L 43mm f/1.9 Special was produced in extremely small numbers (estimates range between 800 and 2,000 units total), making it a modern collector's holy grail [[1]].

Product Lines (LTM Compatible)

Pentax LTM lenses are split between the modern "Special" and the vintage "Tower" optics.

The Pentax-L Special

  • SMC Pentax-L 43mm f/1.9 Special: This is the primary reason Leica users seek out the brand.
    • The "True Normal": Pentax engineers argued that 43mm is the true diagonal of 35mm film (mathematically perfect normal), whereas 50mm is actually a slight telephoto.
    • Design: It is an 8-element design taken from the FA Limited SLR series but re-housed in a high density brass/aluminum barrel with native LTM threading.
    • Render: It features the famous SMC (Super Multi-Coating), known for deep color saturation, high contrast, and ghost resistance. It renders with a distinct "3D" clarity that differs from the lower contrast Mandler era Leica lenses.
    • Ergonomics: It includes a detachable stick type focusing lever and a specialized external viewfinder (since 43mm framelines do not exist on Leica bodies) [[4]].

The Vintage Takumars (Tower Series)

  • Takumar 50mm f/3.5: The standard lens found on Tower rangefinders. It is a rigid, high quality Tessar design.
  • Takumar 50mm f/2.4: A faster, double-Gauss derivative that is significantly rarer.
    • Note: These lenses are often marked "Tower" on the beauty ring but are unmistakable Asahi productions. They offer a classic 1950s look, lower contrast and gentle sharpness, similar to the Elmar or Industar [[3]].

Technical Specifications

Feature Specification Details
Native Mount LTM (Leica Thread Mount)
Focus Coupling Coupled. (The modern 43mm Special focuses down to 0.7m).
Filter Thread 43mm (Pentax-L Special), 40.5mm (Vintage Takumars).
Note: The Pentax-L uses 43mm filters, a deliberate nod to its focal length.
Coatings SMC (Pentax-L Special, Multi-coated)
Single Coated (Vintage Takumars)
Build Materials Anodized Aluminum & Brass (Silver and Black finishes available).
Rarity The Pentax-L Special is extremely rare; prices often exceed $1,000 USD.

Why Photographers Choose Pentax

  • The "SMC" Look: For users who love the punchy, high contrast look of Pentax SLR glass (like the Takumar 50mm f/1.4), the Pentax-L 43mm is the only way to get that specific color signature on a Leica M body.
  • The "Perfect" Focal Length: 43mm sits in the "Goldilocks" zone between 35mm (too wide for some) and 50mm (too tight for others). It provides a very natural, human eye perspective.
  • Build Density: The "Limited" series build quality is legendary. The lenses are machined from solid aluminum and feel colder and denser than even some modern Leica ASPH lenses.

Sources

Lenses (1)

Filters 1 results
Make Model Focal Length Aperture Release year Diameter (mm) Length (mm) Weight (g) Min focus distance Elements Groups Filter diameter (mm) MountModel number(s)Actions
PentaxSMC Pentax-L 43mm F1.9431.920005547230 g1 m7640LTM—