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Asahi Pentax SMC

FotoGearLensAsahi Pentax SMC

SMC: • Pentax 20mm 4.0

Pentax-A 50mm 1.2

Soft 85mm
Telephoto: • 100mm

200mm

300mm Green Star

400mm
Tele-Zoom: • 135-600mm
Super-Tele: • f4.5 500mm

Rare f5.0 500mm

1000mm
Reflex: • 400-600mm Reflex

1 • Asahi Pentax SMC Wide 20mm f/4.0 PK + Rare Hood with Case

The Asahi Pentax SMC 20mm f/4 is a celebrated, ultra-compact manual-focus wide-angle lens originally designed for full-frame 35mm film cameras. It is renowned for its pancake-like dimensions, optical quality, and robust metal construction.

Pentax produced two distinct versions of the 20mm f/4 lens in the K-mount era:
• SMC Pentax (K) (1975–1977): The original 20mm, which featured a larger 58mm filter thread and a 12-element, 10-group optical design.
• SMC Pentax-M (1977–1984): The legendary "M" series version. It was completely redesigned to be the smallest 20mm lens Pentax ever made. It shrunk the filter size to 49mm and simplified the optical formula while maintaining excellent sharpness.

• FOV: 94° • Minimum Focus: 9.8" • Weight: 300 grams • Dimensions 63 x 57mm
• f4.0 - 22.0 • Filter: 58mm

1 • Asahi Pentax SMC M 50mm f/1.2 PK + Rare Hood

The 50mm f/1.2 stands out in Pentax's lineup because, strictly speaking, it is not an "M" series lens despite often being categorized as one by photographers. It belongs to the original "SMC Pentax" (K-series) lineup, which preceded the smaller, lighter M-series lenses. It was Asahi Optical's fastest SLR lens.

There are two primary iterations of this ultra-fast prime:
• SMC Pentax (K-version) (1975–1984): The original lens, known for its all-metal build, long focus throw, and heavy weight. Engravings slightly changed from "SMC PENTAX 1:1.2/50" on early models to "smc PENTAX 1:1.2 50mm" on later ones. A special gold-plated version was also produced in tandem with the Gold Pentax LX camera.
• SMC Pentax-A (1984–2004): An updated version that added an "A" setting on the aperture ring, which allowed the camera body to automatically control the aperture (shutter priority and program modes).

• Production Year: 1975–1984 • Minimum Focus: 17.7" • Weight: 386 grams • Dimensions 65 x 49mm
• f1.2 - 22.0 • Filter: 52mm

2 • Asahi Pentax SMC Soft 85mm f/2.2 PK + Hood

The SMC Pentax 85mm f/2.2 Soft is a rare, manual-focus prime lens built for the Pentax K mount. It was manufactured between 1986 and 1990. Unlike normal lenses, it uses intentional lens flaws to create a dreamy, glowing "soft focus" effect/
How the Softness Works: The lens relies on uncorrected spherical aberrations. The aperture ring has no click-stops and acts as the "softness control". Shooting wide open at f/2.2 gives the most dreamlike, glowing effect. Stopping the lens down toward f/5.6 cuts away the outer light paths and makes the image significantly sharper.

• Production Year: 1977 • Minimum Focus: 22.4" • Weight: 235 grams • Dimensions 72 x 52mm
• f2.2 - 5.6 • Filter: 49mm

• Pentax SMC Tele-Zoom

3 • Asahi Pentax SMC Telephoto 100mm F2.8 PK

Introduced in 1977 as part of the Pentax M-series, this lens was designed to offer excellent optical performance in a drastically smaller and lighter package than its predecessor, the SMC Pentax 100mm f/2.8. The M-series was specifically created to complement compact SLRs like the Pentax MX and ME. Optically, the lens utilizes a 5-element, 5-group design. It features Pentax’s legendary SMC coating, which was industry-leading at the time for maintaining contrast and preventing ghosting. The lens delivers high central sharpness wide open at f/2.8, making it an exceptional portrait lens. Stopping down to f/4 or f/5.6 significantly increases edge-to-edge sharpness.

• Production Year: 1977 to 1984 • Minimum Focus: 3.3 ft • Weight: 360 grams • Dimensions 65 x 61mm • f2.8 - 22.0 • Filter: 49mm Front

4 • Asahi Pentax SMC Telephoto 200mm F2.5 PK

The SMC Pentax 200mm f/2.5 is a classic, manual-focus telephoto prime lens made for Pentax K-mount cameras. Released in 1977 and produced until 1986, it holds the title of the fastest 200mm lens Pentax ever produced.

• Production Year: 1982 • Minimum Focus: 6.6 ft. • Weight: 950 grams - 2.1 lbs • Dimensions 89 x 145mm • f2.5 - 32.0 • Filter: 77mm Front

5 • Rare Asahi Pentax SMC M ★ Green Star 300mm f4.0 PK

The SMC Pentax-M★ (Star) 300mm F4 (often called the "Green Star" due to the green accent ring and star logo) was a groundbreaking, professional-grade manual focus telephoto lens. It holds a special place in history as the very first "Star" (★) lens Pentax ever produced, a designation reserved for their elite, high-performance optics.

• Uniquely Compact: Pentax designed this lens to be incredibly small and lightweight compared to previous 300mm lenses. Users often note that the rear body feels thin like a 200mm lens, while the front bulges out to hold the large 77mm glass element.
• Elite Glass: As a "Star" series lens, it utilized early extra-low dispersion (ED) glass and Pentax’s premier Super Multi-Coating (SMC). This setup yields high contrast, minimal color fringing (chromatic aberration), and excellent sharpness even when shot wide open at f/4.
• Built-in Hood: The lens features a built-in sliding hood. Curiously, Pentax also created a very rare, separate matching screw-on hood that could be reverse-mounted for storage.

• Production Year: 1982 • Minimum Focus: 13.1 ft. • Weight: 830 grams • Dimensions 84 x 132mm
• f4.0 - 32.0 • Filter: 77mm Front

6 • Asahi Pentax SMC M 400mm f5.6 PK

SMC Pentax 400mm f/5.6 lenses refer to a lineage of high-quality, super-telephoto prime lenses produced by Pentax across different mount generations. These lenses are highly regarded by vintage glass enthusiasts for their excellent build quality, built-in slide-out sun hoods, and impressive sharpness even when shot wide open at f/5.6. Because Pentax used the "SMC" (Super Multi Coating) designation across several decades, the phrase usually points to one of the following key variations:

• SMC Pentax (K-Series) & Pentax-M 400mm f/5.6: These represent the transition to the bayonet K-mount. The M-series variant is physically smaller ("miniaturized") compared to its massive predecessors, but remains quite sharp and robust. It lacks modern electronic communication with the camera.

• Production Year: 1974 • Minimum Focus: 16.4 ft. • Weight: 1215 grams • Dimensions 85 x 277mm
• f5.6- 45.0 • Filter: 77mm Front

7 • Rare Asahi Pentax Zoom Lens 135-600mm f6.7 PK + Hard Case

The SMC Pentax Zoom 135-600mm f/6.7 is a legendary, ultra-rare super-telephoto manual focus lens built like a tank. It was introduced by Asahi Pentax in 1975 alongside the launch of the original K-mount system. Known for its massive size and unique drop-in filter system, it was primarily aimed at professional sports, press, and wildlife photographers who needed ultimate reach.

• Production Year: 1977 • Field of View: 6.2-4.1° • Minimum Focus: 20.0 ft or 9.3 ft with Close Up • Weight: 4,070 grams 9 lbs • Dimensions 105 x 589mm
• f6.7 - 45.0 • Filter: 52mm Rear - 95mm Front

8 • Rare Asahi Pentax Reflex Zoom Lens 400-600mm f8.0 PK

The SMC Pentax 400-600mm F8-12 Reflex Zoom is an exceptionally rare and unique piece of photographic history, widely recognized as the only mirror zoom lens ever produced by a major camera manufacturer. Produced between 1984 and 1999, this extreme-telephoto manual-focus lens utilizes catadioptric (mirror) design principles to offer a massive focal range in a remarkably short barrel length.

• Production Year: 1982 • Field of View: 6.2-4.1° • Minimum Focus: 9.8' • Fixed at F8 (at 400mm) changing dynamically to F12 (at 600mm). • Filter: 67mm Filter

9 • Asahi Pentax SMC Lens 500mm f4.5 PK + Case

• Production Year: 1980 • Field of View: 5.0° • Minimum Focus: 32.8 feet • Dimensions: 128mm x 386mm • 3,370 grams 7.43 lbs • f4.5-45.0 • Filter: 52mm Rear Filters

10 • Rare Asahi Pentax SMC Lens 500mm f5.0 m42/PK + Leather Case

Version 4 (SMC Pentax K-Mount, 1975–1986): Very Rare. When Pentax transitioned to the K-mount, they kept manufacturing the 1000mm f/8 on a limited basis. Total production numbers remain exceptionally low across its 11-year run. Finding an Asahi Takumar 500mm f/5.0 complete with its original hard trunk case and metal push-on front cap elevates it from "very rare" to a true museum-grade collector's item. While roughly 2,700 lenses were manufactured], it is estimated that fewer than 10% to 15%survive today on the market as a complete, matching kit.

• Production Year: 1965 • Field of View: 5.0° • Minimum Focus: 34.4 feet • Dimensions: 143mm x 738mm • 2850g 6.28lbs • f5.0-22.0 • Filter: 52mm Rear Filters

11 • Rare Asahi Pentax SMC Lens 1000mm f8.0 PK + Hard Case

Version 4 (SMC Pentax K-Mount, 1975–1986): Very Rare. When Pentax transitioned to the K-mount, they kept manufacturing the 1000mm f/8 on a limited basis. Total production numbers remain exceptionally low across its 11-year run.

• Telescopic Focus: The lens completely lacks a traditional focusing ring. Instead, dual side-mounted knobs control a rack-and-pinion focusing mechanism, operating exactly like an astronomical telescope.
• Built-in Sighting Scopes: Because the field of view is incredibly narrow, it features mechanical front and rear sighting scopes on top of the barrel to help you locate and align distant subjects before looking through the camera.
• Drop-in Filters: Due to the enormous size of the front glass element, standard front filters are not used. The lens relies on 52mm filters inserted via a rear drop-in slot.

• Production Year: 1975-1986 • Field of View: 1.4° • Minimum Focus: 98.0 feet • Dimensions: 143mm x 738mm • Weight: 11.66 lbs with case 25.5 lbs
• f8.0-45 • Filter: 52mm Rear