Pentax 300mm f/4 Lens — Specs, Reviews, Used Prices

Pentax 300mm f/4 SMC Takumar M42 Lens

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Lens Overview — Pentax 300mm f/4

The Pentax 300mm f/4 SMC Takumar is a vintage manual focus telephoto lens built for M42 screw mount cameras, manufactured during the 1960s. Designed around the 35mm film format, this lens carries the classic SMC Takumar lineage that earned a strong reputation among film photographers of that era. The M42 screw mount — sometimes called the Praktica or Universal Thread Mount — was one of the most widely adopted lens mounts of the mid-20th century, and lenses built to that standard have enjoyed a long second life in the digital age thanks to the availability of M42 adapters for a wide range of modern camera systems.

At 300mm, this is a serious telephoto offering for a vintage optic, suited to subjects at a distance. The lens is strictly manual focus, consistent with the optical and mechanical design philosophies of 1960s SLR lenses. Weighing in at 1,120g, it has a substantial, all-metal build typical of the period.

For collectors, film shooters, or photographers who enjoy adapted vintage glass, this Takumar represents a tangible piece of photographic history from one of Japan's most respected optical manufacturers.

Key Features — Pentax 300mm f/4

300mm f/4 Telephoto: A fast maximum aperture for a 300mm prime, allowing for shorter shutter speeds and better subject separation than slower telephoto alternatives.

M42 Screw Mount: Universal thread mount is widely adaptable to modern mirrorless and DSLR systems via inexpensive M42 adapters, including Sony E, Fuji X, and Micro Four Thirds.

SMC Takumar Coating: Super Multi-Coating reduces flare and ghosting, and is regarded as one of the finest lens coatings produced by Pentax during the era.

All-Metal Construction: Solid build typical of classic Japanese optics, contributing to the lens's substantial weight and long-term mechanical durability.

Manual Focus Only: Fully mechanical focus ring with no electronic components, making it compatible with any camera body via a simple mechanical adapter.

35mm Full-Frame Coverage: Image circle designed for 35mm film covers full-frame digital sensors without vignetting when adapted to modern cameras.

Lens Specifications — Pentax 300mm f/4

Pentax 300mm f/4 full specifications
Spec	Detail
Use Cases	Wildlife, Sports, Birding
Lens Mount	M42 Screw Mount
Focus Type	Manual Focus

Description — Pentax 300mm f/4

The Pentax 300mm f/4 SMC Takumar is a manual focus telephoto lens built for M42 screw mount cameras, manufactured during the 1960s. Designed to cover the 35mm film format, it is natively compatible with 35mm SLR film cameras and, via M42 adapters, can be mounted on a wide variety of modern digital camera systems. The lens tips the scales at 1,120g, reflecting the substantial all-metal construction common to Japanese lenses of this era.

As a strictly manual focus optic with a mechanical operational character, it demands a deliberate, hands-on shooting approach. Its 300mm focal length makes it a capable telephoto choice for film photographers and vintage lens enthusiasts alike. Whether you are shooting on 35mm film or exploring adapted vintage glass on a digital body, this SMC Takumar offers a direct connection to a celebrated chapter in photographic history.

Pros — Pentax 300mm f/4

✓M42 screw mount offers broad adaptability to many modern camera systems via widely available adapters
✓300mm focal length provides significant telephoto reach for a vintage optic
✓Manufactured in the 1960s, representing a collectible piece of classic Japanese optical craftsmanship
✓Designed for the 35mm film format, making it directly usable on 35mm film SLR cameras without modification
✓Solid 1,120g build weight suggests the robust all-metal construction typical of the SMC Takumar era

Cons — Pentax 300mm f/4

✗Manual focus only — no autofocus capability, which requires more skill and patience when shooting moving subjects at 300mm
✗At 1,120g, the lens is heavy and may require additional support when used on a tripod or adapted to a mirrorless body
✗M42 screw mount requires an adapter for use on modern digital cameras, adding cost and potentially affecting infinity focus or metering
✗Age of manufacture (1960s) means any individual copy may show wear, haze, or fungus consistent with decades of use and storage

Videos — Pentax 300mm f/4

Is Bigger Better? - TAKUMAR 300MM F/4 REVIEW — Mark Holtze

Frequently Asked Questions — Pentax 300mm f/4

What camera mount does this lens use?+

This lens uses the M42 screw mount, also known as the M42 Universal Thread Mount. It is compatible with M42 screw mount cameras and, with appropriate adapters, can be used on many modern digital camera systems.

Does this lens support autofocus?+

No. The Pentax 300mm f/4 SMC Takumar is a manual focus lens. All focusing must be done by hand using the focus ring on the lens barrel.

What film format is this lens designed for?+

This lens is designed for the 35mm film format, making it fully compatible with 35mm SLR film cameras equipped with an M42 screw mount.

How heavy is this lens?+

The lens weighs 1,120g. Buyers should plan for appropriate support when mounting it on a tripod or adapting it to a lighter mirrorless camera body.

When was this lens manufactured?+

According to the specifications, this lens was manufactured between 1960 and 1969, placing it firmly in the classic era of SMC Takumar optics.

Is this lens compatible with digital cameras?+

The lens is natively designed for M42 screw mount cameras. It can be adapted to many digital camera systems using an M42 adapter, though autofocus and electronic communication will not be available. Compatibility depends on the adapter and the specific digital camera body.

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