Kyoei 135mm f/3.5 Acall

[ulf]

Last Update: 03 April 2021 agb/label/title

Finalized: Work in progress.

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Kyoei 135mm f/3.5 Acall

 

Manufacturer: Kyoei Optical Co. Ltd.

Manufacturer's lens designation: Kyoei Optical Co. Ltd. Acall 135mm 1:3.5 No.<serial number>

Currently manufactured: No

 

Lens type: Manual focus, Prime, Short Tele Lens

Design: TBD

Focal length: 135mm

Aperture range: f/3.5 – f/22, Preset Manual, 12 blades

Focus Range: 4.5 feet to infinity

Sensor format/coverage: up to 24 mm x 36 mm

Mount: M42 x 1 thread

Helicoid: Yes

Flange Focus distance: M42/45.46 mm,

Front filter: 46 mm x 0.75 mm

Introduction year: between 1965 and 1970???

S/N of test object: 80050

 

Image of test object:

Transmittance Summary

Definitions of the parameters below

• Range: This Soligor 1:3,5 f=135mm transmits from 1-80% in an increasing slope from 330nm to 400nm.
• T_VISmax (%) = 90%
• T_400nm (%) = 86%
• T_365nm (%) = 66%
  This high percentage is an indicator for relatively short exposure time under typical UV-pass filtration peaking around 360 nm or when using 365 nm UV-LED illumination.
• λ_{UV HMvis}(nm) = 352nm
• λ_{UV HM400}(nm) = 351nm
• λ_{UV Zero}(nm) = 330nm
• These three values indicate that the lens is marginally working even for some shorter wavelength UV-A photography with some filters and the few for this, suitable cameras.

Spectral Transmission Graphs

UV-NIR, Kyoei 135mm f/3.5

The transmission measurement accuracy into the end of NIR range is less good due to limitations in the light source.

 

UV, Kyoei 135mm f/3.5

UV-Log, Kyoei 135mm f/3.5

Numerical Spectra Data available: Pending

 

General comments about the UV-reach:

tba

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Filters and how to use them on this lens:

The front filter thread is a 46mm standard filter thread.

 

It is also possible to use rear mounted filters, either in lens mount adapters for mirrorless cameras like Sony A-series etc, or placed directly in the camera.

 

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Handling and focussing:

TBD

 

Flare and sun-stars:

TBD

 

Sharpness:

TBD

 

Lens distortion:

TBD

 

Chromatic Aberration in UV:

TBD.