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 Macro-Takumar 1:4/50 is a full-frame manual macro lens which exists in several incarnations:
- Macro-Takumar (1966-1969) – has pre-set aperture with 8 blades, minimum focus distance of 20.8 cm and weight of 265 g. Allows close-up shooting at a magnification ratio of 1:1 (life-sized reproduction);
- Super-Macro-Takumar (1969-1971) — has early type of coating, allows to select manual or automatic aperture mode by a special switch on the housing. Only 5 aperture blades, minimum focus distance of 23.4 cm, weight 248 g. Close-up shooting at magnification ratio of 1:2 «only»;
- Super-Multi-Coated Macro-Takumar (1971-1979) – multicoated, allows metering without preliminary closing the diaphragm to shooting aperture. Other characteristics are the same of Super-Macro-Takumar’s.
- smc Pentax (1975-1977) – has the best build quality among the smc Pentax lenses. Optically the same as the Super-Macro-Takumar;
- smc Pentax-M (1977-1984) — the build quality is also very high but both the length and weight of the housing are slightly reduced. Optically the same as early smc Pentax/Super-Macro-Takumar.
Automatic aperture version of smc Pentax model does not exist because the Pentax Corporation choosed to produce a more ambitious macro lens with the same focal length of 50 mm but with a F/2.8 aperture.
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, Macro-Takumar 1:4/50 does not exist in such variation.
So, we have determined that our sample of Super-Multi-Coated Macro-Takumar 1:4/50 is the ultimate version in the line of Asahi M42 lenses.
In this review the lens was used with the Canon 5D camera via M42 – Canon EF adapter without chip. There was no focus confirmation, but the metering was performed by the camera automatically in the stop-down mode. Theoretically 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 viewfinder. The problem however is that Auto ISO feature is available with this camera only in fully automatic mode and the images are stored in JPEG format only (hence the picture quality will suffer from software compression). Moreover the ISO range which camera selects automatically in this mode is limited to the range of 100 — 400 only, which is insufficient in some cases. That’s why I had to shoot in Tv (shutter priority) mode and periodically look at the images the camera displays immediately after they are made, and if the picture was wrongly exposed, I had to decrease the shutter speed or to increase the ISO value. However soon I get used to such procedures and performed them «automatically».
Build Quality and Characteristics
The build quality of the lens is great (in fact, this is pretty typical for the most lenses of 1970s) 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 the light weight of 248 g and a length of 59 mm (when focused on the infinity; not including the caps).
The manual focus ring has width of 21mm, is 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 24-25 mm when focusing on the minimum distance of 23.4 cm. There is a distance scale and depth of field scale of course. Furthermore, the upper part of the manual focusing ring has maginfication scale marks. If you set the distance scale at the minimum focus of 23.4 cm, you could obtain the magnification ratio of 1:2. With further rotation of the manual focusing ring towards infinity the magnification ratio changes nonlinearly: at ~28 cm it’s 1:3, at ~37 cm — 1:5, at 60 cm — 1:10, at 150 cm — 1:25.
The aperture ring has the following markings: 4 — 5.6 — 8 — 11 — 16 — 22. There are half stops between F/4 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 only 5 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. Both smc Pentax and smc Pentax-M versions of this lens have the same number of aperture blades.
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. As for the hood, the lens does not really need it because the front element of the lens is deeply recessed in the housing.
Optically the lens is pretty simple and consists of 4 elements in 3 groups. The optical elements of the reviewed lens have no any noticeable yellow cast (a common characteristic of many Asahi Super-Takumar lenses).
Paradoxically the focusing with the full-frame SLR Canon EOS 5D camera in manual mode is noticeably more comfortable than with the APS-C mirrorless Fujifilm X-Pro1. There are several reasons. The X-Pro1 is equipped with electronic viewfinder (EVF) and window finder and of course supports Live View mode. In EVF mode you see exactly the image that the camera will record to the memory card, but the viewfinder itself is not very big, so the accurate focusing is sometimes problematic. As for the Canon EOS 5D, it’s an old SLR camera and it does not equipped not only with an EVF (which is quite understandable), but — suddenly — does not offer Live View mode! But fortunately it has a really large optical viewfinder (OVF) so there are no problems when focusing at the maximum apertures — the sharpness of the subject achieved by the rotation of the manual focusing ring could be noticed immediately. However, you should be informed that the image in the OVF could not be called bright already at F/4 and with the further closing of the aperture the OVF gets noticeably darker and the manual focusing becomes not so comfortable as with fast lenses.
The lens exhibits very good sharpness and overall contrast in the center of the frame already from F/4. The sharpness and overall contrast visually increase with further closing of the aperture. The corners of the frame are very soft at F/4, improved at F/5.6 but a bit blurry even at F/8. The depth of field is narrow even at F/4 and if you want, you could achieve truly impressive separation of the main subject from the background. But please be informed that focusing handheld at minimum focus distance is very difficult because even the slightest movement of the hand is pretty enough for the sharpness to be lost. Fortunately there are no problems when shooting at the infinity.
The lens has weak vignetting at F/4, it looks like a slight darkening of the corners of the frame. Just close down the aperture down by one stop and the vignetting is gone. The distortion is not visible. The same goes for the lateral chromatic aberrations.
The quality of the bokeh is very good. The background blur is soft and it is possible to achieve a very smooth transition between the foreground and background blur. 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/4 in the center of the frame but become pentagons starting from F/5.6. The out-of-focus highlights become ellipses at F/4 at the corners of the frame due to mechanical vignetting. However, you should understand that you have to close the aperture up to F/16 or even F/22 when shooting with macro lenses and the depth of field at such apertures will be so wide that you won’t have any chance to see pentagons in your photos.
Longitudinal chromatic aberration (colored halos in front of the focus point and in the background) are virtually absent.
The Asahi Super-Multi-Coated Macro-Takumar 1:4/50 is an excellent macro lens. Mechanically and optically the lens does not leave to be desired for anything more — the lens is ergonomic, easy to use and very sharp all over the frame at any given aperture. The background blur is soft and smooth even taking into account that this is not a fast lens. There are no visible optical aberrations except for the slight vignetting at F/4. The maximum magnification ratio of 1:2 is the same as that of most of modern macro lenses with similar focal lengths of 40-60 mm.
Author of the review and photos: Evgeny Artemov, firstname.lastname@example.org