Asahi Optical Co., Ltd. was founded by Kumao Kajiwara in 1919 in Japan and became one of the leading manufacturers of photo cameras and lenses. The production of photo lenses started in 1931 but the true success came to Asahi only in 1951 when Asahiflex — first Japanese 35 mm SLR camera — came out. First Takumar lenses for Asahiflex camera had M37 thread mount, after some time the M37 thread was replaced by M42 and the lenses with M42 mount were produced till 1975 when threaded mount was abandoned due to release of the new Pentax system based on K bayonet mount.
Asahi Takumar 1:3.5/135 is a full-frame manual telephoto prime which exists in lots of incarnations:
- Takumar (1958-1961) – has black housing with chromed inserts. Preset aperture. Optically consists of 5 elements in 4 groups, minimum focusing distance of 1.80 m, 46 mm filter thread, weight 300 g;
- Takumar (1962-1962) – MFD 2 m, other characteristics are the same of Takumar’s (1958-1961);
- Auto-Takumar (1960-1963) – semi-automatic aperture, MFD 1.8 m, 49 mm filter thread, weight 317 g;
- Super-Takumar (1962-1966) – has early type of coating, allows to select manual or automatic aperture mode by a special switch on the housing. MFD 1.5 m, weight 350 g, the other characteristics are the same of Auto-Takumar’;
- Takumar (1963-1965) – fully black housing, preset aperture, MFD 1.5 m, 46 mm filter thread, weight 315 g;
- Super-Takumar (1966-1971) – has early type of coating, allows to select manual or automatic aperture mode by a special switch on the housing. Optically consists of 4 elements in 4 groups, MFD 1.5 m, 49 mm filter thread, weight 343 g;
- Super-Multi-Coated (1971-1979) — multicoated, allows metering without preliminary closing the diaphragm to shooting aperture. Other characteristics are the same of Super-Takumar (1966-1971);
- smc Pentax (1975-1977) — has the best build quality among the smc Pentax lenses;
- smc Pentax-M (1977-1986) — the build quality is also very high but both the length and weight of the housing are slightly reduced. Besides the optical scheme is more complicated and consists of 5 elements in 5 groups and the number of aperture blades increased from 6 to 8.
In 1980-90s the Pentax Corporation «resurrected» Takumar brand for the series of single-coated budget lenses. Such lenses were marked as Takumar (Bayonet) to distinguish them from the old threaded ones. Thanks God, Takumar 1:3.5/135 Bayonet does not exist.
So, we have determined that our sample of Super-Takumar 1:3.5/135 is the ultimate variation (1966-1971) in the line of Asahi M42 lenses. In this review the lens was used with the Fujifilm X-Pro1 camera with a crop factor of 1.53, and the effective focal length of the lens «became» 206.5 mm (full-frame equivalent). The lens was used via M42 — Fuji X adapter without chip. There was no focus confirmation, but the metering was performed by the camera automatically in the stop-down mode. All you have to do is just to select the desired aperture and rotate the manual focus ring until you have your subject sharp in the EVF or LCD in Live View mode.
Build Quality and Characteristics
The build quality of the lens is great (in fact, this is pretty typical for the most lenses of the late 1960s) and is not comparable not only to the modern high-quality plastic lenses, but even to the all-metal Pentax Limited series of lenses. The black housing of the lens is completely made of metal, including thread mount, has a moderate weight of 343 g and a length of 91.8 mm (when focused on the infinity; not including the caps). The condition of the tested lens is excellent: almost no scratches, dents etc.
The manual focus ring is very wide (42 mm), well damped, has no play, rotates smoothly and with proper resistance. The condition of various control elements of the lens depends on the year of manufacture and the level of preservation of a particular lens. The angle of rotation of the ring is very big (approximately 340 degrees) and more than sufficient to provide very accurate focusing. The front element is pushed forward by 15 mm when focusing on the minimum distance of 1.5 m. There is a distance scale and a detailed depth of field scale of course.
The aperture ring has the following markings: 3.5 — 5.6 — 8 — 11 — 16 — 22. There are half stops between F/3.5 and F/16 but they are not indicated on the scale. The aperture works in manual and automatic modes, there is a corresponding switch on the rear part of the housing. The switch is irrelevant for today’s digital cameras.
The aperture has 6 blades, its opening is not circular, but this is not so surprising, because the production of the lenses with a circular aperture started only in 1987 by the Minolta Corporation — 12 years after withdrawal of Asahi Takumar lenses from the production.
The diameter of the filter thread is 49 mm — a common size among Asahi (Pentax) lenses. The filter thread does not rotate when focusing, making it easy to use polarizing and gradient filters. No filters were used during shooting for this review.
Optically the lens consists of 4 elements in 4 groups. Models before 1966 are based on 5 elements in 4 groups. The Super-Multi-Coated (1971-1979) has more advanced multicoating which teoretically result in greater resistance to flares and ghosting and better overall contrast of the images.
The optical elements of the reviewed lens absolutely have no any noticeable yellow cast (a common characteristic of many Asahi Super-Takumar lenses).
The lens exhibits very good sharpness in the center of the frame already from F/3.5. With closing of the aperture the sharpness increases rapidly and is great from F/5.6. The overall contrast remains excellent and unchanged on every aperture. The quality of edges of the frame with X-Pro1 APS-C sensor are visually not far behind from the center of the frame.
The depth of field at F/3.5 is narrow even on APS-C sensor and if you want, you could achieve truly impressive separation of the main subject from the background.
Vignetting is not noticeable with APS-C sensor, the same goes to distortion and lateral chromatic aberration.
The quality of the bokeh is very good. The background blur in most cases is very smooth and soft and achieved easily (thanks to large focal length and fast aperture of the lens). The degree of blurring, however, also depends on the distance between the front element of the lens and the subject, the distance between the subject and the background.
The out-of-focus highlights are round and evenly rendered at F/3.5, but become hexagons starting from F/5.6. It’s a bit disappointing considering the overall magnificent lens optical results.
Longitudinal chromatic aberration (colored halos in front of the focus point and in the background) of this lens are clearly visible at F/3.5 on contrast transitions, water droplets, shiny metal surfaces, etc. The effect is significantly reduced from F/5.6 and no longer affects the image quality.
The Asahi Super-Takumar 1:3.5/135 is very interesting manual focus telephoto lens when used with APS-C sensor. It is reasonably priced and for the money you receive the focal length of 135 mm, narrow depth of field, beautiful bokeh and very smooth background blur at F/3.5 and sharp images at every aperture.
Author of the review and photos: Evgeny Artemov, firstname.lastname@example.org