Nikon 50mm f/2.8 EL-Nikkor: old metal version

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Finalized: Work in progress.

Last Update:

 

Nikon 50mm f/2.8 EL-Nikkor:. old metal version

 

Manufacturer: Nikon

Manufacturer's lens designation: EL-NIKKOR 50mm f/2.8

Currently manufactured: No

Lens type: Enlarger lens for film up to 24mm x 36mm ( Ø43.2mm )

Focal length: 50mm

Aperture range: f/2.8 – f/45, Manual, 8 blades

Design: 6 elements in 4 groups

Flange Focus distance: 44.8mm

Recommended magnification range*: 0.05x – 0.5x.

Optimal magnification *: 0.125x

Mount: M39 x 26tpi thread.

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

Front filter: 40.5 mm x 0.5 mm

Introduction year: pre 1960?

S/N of test object: 343805

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

 

Lens review (VIS), on the web:

Lens Manual on the web: http://www.savazzi.n...El-Nikkor_2.pdf

 

Image of test object:

 

Transmittance Summary

Definitions of the parameters below

• Range: The El-Nikkor 50/2.8 Old Metal lens transmits 0-80% in an increasing slope from 332 nm to 400nm.
  
• T_VISmax(%) = 84%
  
• T_400nm(%) = 80%
  
• T_365nm(%) = 56%
  This percentage is an indicator for moderately short exposure time under typical UV-pass filtration peaking around 360 nm.
  

• λ_{UV HMvis}(nm) = 357nm
  
• λ_{UV HM400}(nm) = 356nm
  
• λ_{UV Zero}(nm) = 332nm
  
• These three values indicate that the lens is primarily UV-capable in the UV-A range using UV-pass filtration peaking around 365 nm or higher.
  

Spectral transmission graphs:

UV-NIR, EL-NIKKOR 50mm f/2.8, old metal version

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

 

UV, EL-NIKKOR 50mm f/2.8, old metal version

 

UV-Log, EL-NIKKOR 50mm f/2.8, old metal version

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Filters and how to use them on this lens:

The front filter thread is common and can be adapted to other filter sizes buy a simple step ring.

 

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.

 

An alternative, if space in the camera allows, is to putty-mount a filter directly against the lenses rear element mount ring.

The rear lens element is recessed and thus safe and the ring provides a good reference plane for orienting the filter normal to the optic axis.

 

My Omega 330W80 Improved Ø25mm, is mounted in a 27mm-filter ring and works well to mount as it is.

 

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Handling and focusing:

This lens needs to be combined with a helicoid or macro bellows to set desired magnification.

With short enough minimum length of a short helicoid it is easy to obtain focus at infinity with mirrorless cameras.

However the standard adapters for M42-lenses to mirrorless cameras will not give focus at infinity.

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