Leitz 60mm f/4.5 Focotar

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Finalized: Work in progress.

Last Update:

Note: Additional information or links about this lens are welcomed and will be incorporated into the first post as time permits.

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Leitz 60mm f/4.5 Focotar

 

Manufacturer:Schneider Kreuznach for Leitz Wetzlar, Germany

Manufacturer's lens designation: FOCOTAR 1:4.5 / 60 - LEITZ WETZLAR

Currently manufactured: No

Lens type: Enlarger lens for film up to TBD

Design: TBD

Focal length: 60mm

Aperture range: f/4.5 – f/22, Manual, 8 blades

Format coverage: TBD

Recommended magnification range*: TBD

Optimal magnification*: TBD

^{*Definitions reversed from normal enlarger definition, referring to the motif not the negative-plane}

Mount: M39 x 26tpi thread

Reverse mount: None.

Helicoid: No

Flange focus distance: TBD

Front filter: Only by special filter adapter. See below

Introduction year: 1956

S/N of test object: 2369056

Manufacturing year: 1969

https://www.l-camera...r_1:4.5_/_60_mm

 

Lens review (VIS), on the web:

Lens Manual on the web:

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Transmittance Summary

Definitions of the parameters below

• Range: The Focotar 60mm f/4.5lens transmits 1-73% in an increasing slope from 309nm to 400nm.
  
• T_VISmax (%) = 85%
  
• T_400nm (%) = 73%
  
• T_365nm (%) = 63%
  This low percentage is an indicator for long exposure time under typical UV-pass filtration peaking around 360 nm or when using 365 nm UV-LED illumination.
  
• λ_{UV HMvis}(nm) = 342nm
  
• λ_{UV HM400} (nm) = 337nm
  
• λ_{UV Zero} (nm) = 309nm
  
• These three values indicate that the lens is working for som UV-B photography with suitable filters and a few for this, suitable cameras.
  

Image of test object:

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Spectral Transmission Graphs

UV-NIR, Focotar 60mm f/4.5

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

 

UV, Focotar 60mm f/4.5

 

UV-Log, Focotar 60mm f/4.5

Numerical Spectra Data available: Yes

 

General comments about the UV-reach:

tba

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Filters and how to use them on this lens:

This lens has no front filter thread.

For front mounted filters a step ring of suitable dimensions has to be glued or temporarily putty-mounted onto the aperture adjustment ring that is the frontmost part of the lens

 

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:

This Focotar 60mm f/4.5 must be used with a helicoid or macro bellows to set desired magnification.

On mirrorless cameras the lens's FFD permits focus to infinity with careful sizing of the helicoid or bellows.

However these lenses are designed and optimised for short focus distances. At infinity the result will not be optimal.

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Image samples: