29 Versions of the 55mm Asahi Takumar M42 Screw Mount Lenses

[visualopsins]

29 Versions of the 55mm Asahi Takumar M42 Screw Mount Lenses

Beg, End, Lens, f/#, elements/groups, notes

5/1957, 5/1959, Takumar, 2.2, 5/5, distance in meters
5/1957, 5/1959, Takumar, 2.2, 5/5, distance in feet
5/1957, 5/1959, Takumar, 2.2, 5/5, distance in meters and feet

4/1958, 5/1959, Takumar, 1.8, 6/5(1)

5/1958, 5/1959, Auto-Takumar, 1.8, 6/5(1) , Zebra
5/1958, 5/1959, Auto-Takumar, 1.9, 6/5(1) , Zebra, f/1.8 lens marked 1.9 for US sale with Sears Tower 29 brand cameras made by Asahi Pentax

1959, 1961, Auto-Takumar, 2, 6/5(2), white distance engravings, "1:2 f = 55mm" on name ring
1961, 1962, Auto-Takumar, 2, 6/5(2), yellow distance engravings, "1:2 / 55mm" on name ring

1960, 1962, Auto-Takumar, 1.8, 6/5(2) , ccw rotating aperture ring, reverse direction A/M switch, 1/2 aperture stop between f/11 and f/16

1961, 1962, Auto-Takumar, 2.2, 6/5(1), white distance engravings, chrome aperture ring and dof scale
1962, 1963, Auto-Takumar, 2.2, 6/5(1), yellow distance engravings, black aperture ring

1962, 1963, Super-Takumar, 1.8, 6/5(2), model I, 1/2 aperture stop between f/11 and f/16
1963, 1964, Super-Takumar, 1.8, 6/5(2), model I, no 1/2 aperture stop between f/11 and f/16
1964, 1965, Super-Takumar, 1.8, 6/5(2), model I, no 1/2 aperture stop between f/11 and f/16, 34520 on A/M switch

1962, 1963, Super-Takumar, 2, 6/5(1), Model I, ccw rotating aperture ring with unmarked detent past 2, reverse direction A/M switch
1963, 1965, Super-Takumar, 2, 6/5(1), Model I, cw rotating aperture ring doesn't move past 2, cw A/M

1965, 1966, Super-Takumar, 1.8, 6/5(2), model II, A/M switch labels, blue coatings
1966, 1971, Super-Takumar, 1.8, 6/5(2), model II, Auto/Man switch labels, product 37100, purple coatings
1971, 1971, Super-Takumar, 1.8, 6/5(2), model II, Auto/Man switch labels, product 37101
1971, 1971, Super-Takumar, 1.8, 6/5(2), model II, Auto/Man switch labels, product 37101, with aperture coupling

1965, 1966, Super-Takumar, 2, 6/5(1), Model II, A/M switch labels
1966, 1967, Super-Takumar, 2, 6/5(1), Model II, Auto/Man switch labels, product 37102
1967, 1971, Super-Takumar, 2, 6/5(1), Model II, Auto/Man switch labels, product 37103
1971, 1974, Super-Takumar, 2, 6/5(1), Model II, Auto/Man switch labels, product 37107

1971, 1971, Super-Multi-Coated Takumar, 1.8, 6/5(2), without aperture coupling, product 37101 is same on Super 55/1.8 Model II variation 3
1971, 1972, Super-Multi-Coated Takumar, 1.8, 6/5(2), with aperture coupling, product 37104
1972, 1972, Super-Multi-Coated Takumar, 1.8, 6/5(2), with aperture coupling, product 37106

1972, 1975, SMC Takumar, 1.8, 6/5(2), product 37108

1974, 1977 SMC Takumar, 2, 6/5(2), product 37109

notes:

dates for individual lenses in a group are my guesses based on date range in reference for the entire group and other clues.
6/5(1) -- first 6/5 design
6/5(2) -- second 6/5 design


reference:

The Ultimate Asahi Pentax Screw Mount Guide 1952-1977, Gerjan van Oosten, Uitgeverij Jansz, Zeist, 1999, ISBN 90-76537-02-X

[visualopsins]

Photographers report some of the 6/5 design lenses render better than some others.
The different 6/5 designs could be a major determining factor choosing the better lenses.
However, both printed and online sources differ which lenses use the first and which use the second 6/5 design.

The purpose here is to compare physical samples of the lenses for optical design differences.

First will be visual comparison of the elements.
Later perhaps there will be access to expensive measurement equipment.

Collection thus far has 5 lenses to compare.

1960, 1962, Auto-Takumar, 1.8, 6/5(2) , ccw rotating aperture ring, reverse direction A/M switch, 1/2 aperture stop between f/11 and f/16

1962, 1963, Super-Takumar, 2, 6/5(1), Model I, ccw rotating aperture ring with unmarked detent past 2, reverse direction A/M switch

1971, 1971, Super-Multi-Coated Takumar, 1.8, 6/5(2), without aperture coupling, product 37101 is same on Super 55/1.8 Model II variation 3
1971, 1972, Super-Multi-Coated Takumar, 1.8, 6/5(2), with aperture coupling, product 37104

1974, 1977 SMC Takumar, 2, 6/5(2), product 37109

[D1N0]

[caspert79]

I need that book, i think a new edition is coming.

[Sciolist]

Yep, this is going to be good .

[bringolo]

[quote="caspert79"]I need that book, i think a new edition is coming.[/quote]

A new edition would be very nice indeed. Do you know anything about it?

Second hand copies are insanely expansive:
https://www.vialibri.net/searches/202006241159hmhjImxdpo

[D1N0]

[visualopsins]

[visualopsins]

Here are some measurements from actual lens samples.

The lenses:

A) 1960, 1962, Auto-Takumar, 1.8, 6/5(2) , ccw rotating aperture ring, reverse direction A/M switch, 1/2 aperture stop between f/11 and f/16

B) 1962, 1963, Super-Takumar, 2, 6/5(1), Model I, ccw rotating aperture ring with unmarked detent past 2, reverse direction A/M switch

C) 1971, 1971, Super-Multi-Coated Takumar, 1.8, 6/5(2), without aperture coupling, product 37101 is same on Super 55/1.8 Model II variation 3
D) 1971, 1972, Super-Multi-Coated Takumar, 1.8, 6/5(2), with aperture coupling, product 37104

E) 1974, 1977 SMC Takumar, 2, 6/5(2), product 37109

The measurements:

lens, front element thickness, diameter, 2nd element thickness, diameter

A) 0.280, 1.48, 0.43, 1.34
B) 0.280, 1.48, 0.43, 1.34
C) 0.280, 1.44, 0.42, 1.28
D) 0.280, 1.44, 0.42, 1.28
E) 0.280, 1.44, 0.42, 1.28

Conclusions:

A and B have the same optics
C, D and E have the same optics

last edited 7:50PM PDT 27 June 2020

[Sciolist]

The plot thickens .

[visualopsins]

Lens Clocks, the only way to really compare, are not as expensive as I assumed, actually affordable.

Looking for one....

https://en.wikipedia.org/wiki/Lens_clock

[visualopsins]

The data is suggesting 6/5 lenses produced before 1971 are all 6/5(1) design, and all lenses first produced in 1971 or later are 6/5(2) design.

Variation samples of Super f/2 from before and after 1971, and a lens clock will be arriving next week.

[Smoli4]

I have those two


#1


#2


#3

[D1N0]

Mine are:
1961, 1962, Auto-Takumar, 2.2, 6/5(1), white distance engravings, chrome aperture ring and dof scale (although distance engraving like more like a light yellow/orange and light blue for feet) 468877

1963, 1965, Super-Takumar, 2, 6/5(1), Model I, cw rotating aperture ring doesn't move past 2, cw A/M (I can move the aperture ring a tiny bit past two and it will stay there (no effect on aperture opening since it is behind a round ring) 1108060

1963, 1964, Super-Takumar, 1.8, 6/5(2), model I, no 1/2 aperture stop between f/11 and f/16 1675167

1972, 1975, SMC Takumar, 1.8, 6/5(2), product 37108 79722322 (It has a very untakumarry hitch with some stiffness in the focussing action).

[visualopsins]

[Smoli4]

[visualopsins]

[Smoli4]

[visualopsins]

[visualopsins]

1971, 1974, Super-Takumar, 2, 6/5(1), Model II, Auto/Man switch labels, product 37107
0.280, 1.44, 0.42, 1.28

Looks like 6/5(1) may be wrong. Awaiting Lens Clock...
More evidence for change in 1971.

[visualopsins]

Factors other than possibly different optical schemes, maybe affecting rendering visibly:

Diaphragm: The Auto-Takumar 55/2 preset model has 10-blade diaphragm, more circular than later models with only 6-blade diaphragm.
Coatings: The Auto-Takumar 55/1.8 has coatings different color from Super-Takumar 55/1.8 model I, and Super-Takumar 55/1.8 model II early variation has coatings different color from later variation.

The more circular diaphragm certainly makes a difference in performance with lens stopped down from wide open.
The Auto-Takumar 55/1.8 seems to have more "glow" from oof highights than model I Super-Takumar 55/1.8. I'll try to post some examples to illustrate later.

from ebay seller kosai1970, the Auto-Takumar 55/1.8 preset diaphragm:


credit: ebay seller kosai1970

credit: ebay seller kosai1970

[visualopsins]

Compare two lenses to test theory of change in 1971.

The Auto-Takumar flares easier...



Left: 1960, 1962, Auto-Takumar, 1.8, 6/5(2) , ccw rotating aperture ring, reverse direction A/M switch, 1/2 aperture stop between f/11 and f/16
Right: 1971, 1974, Super-Takumar, 2, 6/5(1), Model II, Auto/Man switch labels, product 37107




Can you see any differences that could indicate lenses have different optical designs?

[D1N0]

In the first set the Auto-takumar has much more contrast than the Super-Takumar. In the second one the Super-Takumar seems to have more contrast. Bubbles of the auto-takumar are a bit larger (1.8 instead of 2) They have a more defined soap bubble effect

[visualopsins]

Sets were made from different angles. The size of the oof highlights depends on degree oof -- those are focused at different distance settings.

I'm going to try to get a better comparison with a better equipment setup using tripod & distance markings and two f/1.8 lenses.

[visualopsins]

Try again.

Left to right -- Auto-Takumar 1.8, Super-Takumar 2 Model I
Top to bottom -- focused, focused to 5ft/1.5m, and minimum focus