Chiyoko 45mm 1:2.8 Minolta Super Rokkor – review

Published by Tony on

Chiyoko Super Rokkor 1:2.8 f=45mm (Minolta) lens review , aka Chiyoko 45mm 1:2.8 Tele Rokkor

Mount – LTM, Leica Thread Mount, or LSM, Leica Screw Mount, or M39

This is the first “Minolta” interchangeable lens for the most popular in the world 35mm standard – the new era has been opened. It is difficult to overestimate its historical significance. In a sense, it can be called as the great-grandmother of modern lenses Minolta/Sony family.

Chiyoko 45mm 1:2.8 Super Rokkor + Minolta-35

Chiyoko 45mm 1:2.8 Super Rokkor specifications

Name engraved on the lens Chiyoko SUPER ROKKOR
f[mm] 45
A max [1/f] 2.8
A min[1/f] 16
Lens design [el.] 5
Lens design [gr.] 3
Filter thread Ø front(rear)[mm] 34
Lens Shade
closefocus[m] 1
Dimension Ø x length [mm] 48/31.3
Weight[g] 160
Year 1947 – 1955(?)
Style
Notes six editions but always the same 5/3 schema

More data

Floating elements NO
Aperture blades number 8
Confidence in the test results of reviewed copies Enough High
Reviewed Lens SN: 7504

Historical note

According to canonrangefinder.org this lens has six versions:

  • 45mm f2.8 first series (1947-1948): serial numbers 20xx, 30xx, 40xx.
  • 45mm f2.8 second series (1948-1949): serial numbers 30xx to 150xx.
  • 45mm f2.8 third series (1949-1951): serial numbers 150xx, 160xx, 170xx. First 45mm f2.8 to have a focusing lever.
  • 45mm f2.8 fourth series (1951-1952): serial numbers 15xx to 200xx. First 45mm f2.8 without the circular opening showing the f-stop.
  • 45mm f2.8 fifth series (1952-1953): serial numbers 135xxx.45mm f2.8
  • sixth series (1953-1955): serial numbers 140xxxx. No provision for the small 19mm filter in the inner lens ring, such as in previous 45mm f2.8 lenses.

The lens was designed for Minolta-35 – rangefinder camera. The first generations of these cameras have a 24x32mm frame, instead of a world standard 24x36mm. So, the unusual 45mm lenses on Minolta-35 provide the same result as much more common 50mm lenses on the cameras produced by other competitors. Chiyoko is noticeably compact and has dimensions close to collapsible 50mm lenses which were enough popular in those times because of sizes but had certain disadvantages.

Naming

About the lens name: it is just a contraction of first syllables of “Chiyoda Cogaku”:

In September 1937, the company became Chiyoda Kōgaku Seikō K.K. (千代田光学精工㈱, meaning Chiyoda Optics and Precision Industry Co., Ltd.), abbreviated “Chiyoko” (千代光) on some logos and publications.[15] (The word Chiyoda was created with the characters 千代, meaning “one thousand generations” and 田, the first character of Tashima’s name; it conveys the meaning that Tashima’s company will last a thousand generations.)[16]

camera-wiki.org

The reviewed copy is perfectly preserved and has no noticeable signs of use that could affect the test results. (Black dots on the glass on some photos are just a result of my carelessness – it turned out to be easy to blow away but I have done it after the photo-session. (Please, forgive me the dust on the lens, I never have the patience to clean objects for close-up photos))

By the way

Almost all four lenses from that rangefinder initial generation have been reviewed, it may help to better understand characters and traits of lenses from that period:

  • 45mm f/2.8 Chiyoko Super Rokkor
  • 8.5cm f/2.8 Chiyoko Super Rokkor
  • 11cm f/5.6 Chiyoko Tele Rokkor
  • 13.5cm f/4 Chiyoko Tele Rokkor

And a few of LTM Minolta later models:

  • 50mm f/2.8 Chiyoko Super Rokkor
  • 50mm f/2.0 Chiyoko Super Rokkor
  • 50mm f/1.8 Chiyoda Kogaku Super Rokkor

Chiyoko 45mm 1:2.8 Super Rokkor lens exterior

Chiyoko 45mm 1:2.8 Super Rokkor mounted on the camera Minolta-35 (Model B)

This is a very authentic combination. I give 99% to the chance that this couple has been purchased as a kit.

Chiyoko 45mm 1:2.8 Super Rokkor sharpness

Сlose-distance resolution test, minimal distance

Testing methods description

  • Target: 10-15 cm picture, printed on glossy photo paper
  • Distance: 1.7m
  • Camera: Sony A7II (24mpx, full-frame, tripod, remote control). M-mode, ISO fixed, WB fixed, SteadyShot – OFF.
  • The test was repeated for every F-stop on every focus position with manual focus adjustment for each shot. That is to avoid the effect of field curvature.
  • RAW processing: Capture One, default settings. All quality settings – 100%. Crops – 300×200 px

Original target image (printed in horizontal orientation on 10cm X 15cm glossy photo paper)

Scene preview

Test results

Long-distance resolution test

Testing methods description

  • Target: cityscape
  • Distance: > 200 meters to center focus point
  • Camera: Sony A7II (24mpx, full-frame, tripod, remote control). M-mode, ISO fixed, WB fixed, SteadyShot – OFF. The focus point is on the center only.
  • RAW processing: Capture One, default settings. All quality settings – 100%. Crops – 300×200 px

Scene preview

Test results

Chiyoko 45mm 1:2.8 Super Rokkor aberrations

Vignetting

Geometric distortion

Coma aberrations

Chromatic aberrations

Long-distance bokeh

Test #1

Test conditions: the lens was focused on minimal distance on the scale (1m), buildings are on “infinity”-distance.

Test#2

Test conditions: lens was focused on 3m

Light bubbles bokeh – long distance

Test #1

The lens is on the minimal focusing distance 1m, lights are on infinity (cityscape)

Test #2

Test conditions: lens was focused on 3m

Chiyoko 45mm 1:2.8 Super Rokkor – final conclusion

The unexpectedly useful lens even from the modern point of view. Honestly, I’m not a fan of such old-school optics and not going to recommend it as a standard lens for every day, but I’m sure – if a photographer is enough skilled this lens may help to create amazing photos.

The most unusual behavior – is the strange sharpness distribution over the frame on long-distances: the lens is able to provide to us amazing center, good corners(!) but weak middle positions. An owner needs to remember about this trait in any aperture up to F8. It isn’t a unique behavior – many rangefinder lenses work in the same way.

And it seems to me that this strange weakness in the middle became one of the reasons for the exciting and “swirly” boke.

Other aberrations quite standard: just a little bit too heavy vignetting may be added into a list of weakness but coma and chromatic aberrations almost absent, the same about geometric distortion – it’s low enough.

Conclusion: the lens is small, lightweight, reliable, can be used on any Leica-M, LTM and mirrorless cameras, has a weakness regarding sharpness in the middle position but still enough sharp and may provide incredible pictures if an owner is ready to play with bokeh. Anyway, I would recommend it to the role of art-tool, but not as a standard lens of everyday photography on modern digital sensors. Grand-grandmother still looks really cool.

Chiyoko ROKKOR 48/2.8 Japanese Common Name “梅鉢”(Umebachi)
梅=plum (Resembles Japanese plum flower)
ja.wikipedia.org
鉢=bowl or pot
The real plum bowl without the lever is the most valuable.

(с) T Rokkor Miura

 


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