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| The basic one.. a 2.4/58mm. The
first standard lens lens for the Asahi-Pentax 1957 ,
"preset" type with dual aperture rings. The preset mechanism works very
fast on these lenses and smooth like silk. Comparing these 3 pictures you can see it's a "long" lens with thick (though not large) front element. 5 elements in 3 groups, you've got a classical Heliar type..! It speaks for Mr. Suzuki's - lens designer at Asahi Optical then - knowledge, or admiration for the German lens design that he took the famous pre-war Voigtlander large format portrait lens as a starting point to design Asahi Opticals first standard lens of higher speed for the "Asahiflex-II" in 1954. This optical computation was then transferred to the M42 mount, as seen here. There is no other Heliar type standard lens for 35mm still photo film that I know of, neither for SLR nor Rangefinder cameras, except a 2001 Voigtlander/ Cosina remake of a much lower speed (f/3.5) |
Hot, very hot already... In 1957
it was not so clear in Optical business which standard lens design will
win the battle - and among three standard lenses sold with the
Asahi-Pentax Original there was only one Gaussian type -
the 2.2/55mm. It had one element less than all later well known
versions.: 5 elements, all isolated - not a common idea in the 1950's
years, if not to say curageous..! This type was kept in production for the Pentax "S" in 1958, with dual scale (feet and meters) and higher S/Ns. I found this rare lens (with feet-scale) lately on a 1959 Pentax H2 - poor camera never used its automatic diaphragms trigger with this preset lens in 46 years... I estimate contrast isn't up to later standards, due to its simpler construction. Don't confuse with the later Auto-Takumar 2.2/55mm which have the modernized 6-elements design! |
Fastest and rarest standard lens in
(1957: Takumar 2.0/58mm Unlike all later types which are Gaussian without exceptions - until present! - this is a Sonnar type (6 elements/ 4 groups, the second groups beeing a cemented triplet). This was also the first Pentax lens with an Infrared marker. In 1957 was the "experimental phase" of Pentax standard lens design which was finished 2 years later. No cocking, no aperture pin, no automatic diaphragm on these early lenses! focussing scale either "meter" or "feet" according to market, never both. Be careful with these screw-mounts (alloy thread!) From this perspective, you can clearly see this lens has much bigger and more protuding "glass" at a very comparable speed than the 2,2/55mm, thus probably leading Mr. Suzuki rightfully to the adoption that the Gaussian design was the best point to start with developing faster apertures like f/1.8 and later, f/1.4 Pictures taken with this lens |
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| For the Pentax K with innert-bayonet
auto-diaphragm-mechanism there was a need for a new set of lenses (also
the 1957 preset series can be used) which supports this feature. The first approach was a semi-automatic diaphragm which needs to be cocked by 90 degrees manually to full aperture (see cocking lever under the "Feet" scale) and was released by the camera when triggered just before shutter fires. Top-of-the-line lens in 1958 was the Auto-Takumar 1.8/55mm, with fasciated focussing ring, now having dual scale "meters" and "feet". Available only with the Pentax K. The solely lens form Pentax in this design. This was also the first of the famous Gaussian design (6 elements in 5 groups) becoming Pentax standard until the next 40 years for the 50-55mm focal length of that speed. |
In
1959 there were 3 "standard" types - now all Gaussian
designs: with 6 elements in 5 groups:
Most of them were later changed to "Super-Takumar" type lenses which worked nicely with the older cameras without need to be cocked. But these later series add size and weight too! There is no difference in glass or performance (except the last S.M.C. types multicoating). So please keep and beware them |
A lens of the 1970's? Wrong! This Auto-Takumar 1.8/55mm was the top-of-the-line lens for the Pentax S3 (1961). Despite of beeing labeled "Auto-Takumar" it was in fact the first full automatic diaphragm lens (no cocking lever, but an Auto/Manual switch) - exactly that what Pentax called later Super-Takumar. This was also the first Pentax standard lens which had the "focussing scale window" (later becoming a typical Pentax characteristic) and the aperture ring next to the camera body. Note that this one runs counter-clockwise! It is also the first standrad lens with an 49mm filter which became standard with Pentax. Older lenses have a smaller 46mm filter. |


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One
of the world first Retrofocus- wideangle lenses - and in 1958 the
fastest SLR 35mm
lens with f/2.3. An argument for press-photographers to buy PENTAX in
these years.... Build until 1962, then replaced by an f/2.0 with even
more
size. But it's build sleek (weight 306g,
length 8.1cm) Probably the first and soley 65mm Filter mount Pentax lens. Chrome lens cap included. A sun shade for this monster? Who knows... |

