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Topic: |
Komuranon-S 5.6/75
Enlarging Lens |
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Author/Copyright: |
John Jovic |
Komuranon-S enlarger or
enlarging lenses were made by Komura Lens MFG. LTD. and sold in various
parts of the world during the late 1970's. The Komuranon-S 75mm F5.6 is a six
element, 4 group enlarging lens.
Specifications
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5.6/75mm
"S"[1] |
| Focal Length (mm): |
75 |
| Maximum aperture (F): |
5.6 |
| Lens construction (elements - groups): |
6-4 |
| Angle of coverage: |
56 |
| Recommended negative size (mm): |
60 x 60 |
| Minimum aperture (F): |
22 |
| Number of aperture blades |
8 |
| Designed magnification: |
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| Useful magnification range: |
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| Achromatized wavelength range (nm): |
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| Distortion at basic magnification (%): |
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| Focal length design value (mm): |
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| Barrel outer diameter A (front) (mm): |
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Flange mount thread size: |
Leica |
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Filter size (mm) |
M40.5x0.5[pc] |
| Barrel outer diameter B (rear) (mm): |
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| flange focal length (mm): |
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| Back focal length (mm): |
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| Distance from flange surface to the
second principal point (mm): |
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| Principal point spacing (mm): |
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| Total length (mm): |
37.5 |
| Weight (g): |
93 |
| Coating: |
four layer coated |
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Application Notes
The lens was fitted to a Canon 5D2
full frame camera using a range of helicoids and bellows.
The method that allowed infinity focus was with a readily available M42 (x1.0) to Canon EF adapter, an M42 (x1.0)
helicoid of approx 13mm-20mm and an M42<M39 adapter to which the M39
mount lens was actually fitted. In this configuration it was not possible to focus
very close at all although infinity focus was easily attained.
A longer helicoid of approx 17mm-30mm was also tested which allowed
close focusing but without allowing infinity focus.
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The Komuranon-S 5.6/75
is shown here fitted to a Canon 5D2 with a short helicoid. |
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The lens was also tested using a Canon 5D2 with a Nikon PB-4 bellows.
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The Komuranon-S 5.6/75
is shown here fitted to a Canon 5D2 with a Nikon PB-4 bellows. |
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The Komuranon-S 5.6/75 has a filter thread which enables filters and
lens hoods to be used. Note however that like all Komuranon E and S
enlarging lenses the filter thread appears to be there by accident rather than
design as it is the thread left over from that used by the bezel which
holds down the front element. Some lenses have excess exposed thread
which allows a filter or lens hood to be fitted whilst some lens don't
have any exposed thread left over after the bezel is fitted.
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The lens hood is
fitted to the Komuranon-S 75mm F5.6 using an M40.5x0.5 adapter. |
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Sample Images
The above animation shows that the Komuranon-S 5.6/75 has
excellent illumination across the frame at all apertures with only
minimal vignetting at 5.6. The centre value in every vignetting sample
image (above) is exactly the same. Any vignetting
appears as a darkening of the images from the centre towards the edges. This test was performed with a short helicoid
(approx 13mm-20mm) and with the lens focused at infinity. The lens did
not show any sign of a flare spot or hotspot. No lens hood was used in this
test.
The sample images below were all photographed with a Canon 5D2 camera
and with a lens hood fitted, unless stated otherwise.
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References |
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[tbc] |
To Be Confirmed. The information has not been
confirmed by a credible source. |
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[pc] |
Photo Cornucopia. Measured or personally observed
by the Author. |
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[1] |
Hindaphoto Inc. Komura Facts. USA. nd
also
"Komuranon-S Enlarging Lenses."
http://photocornucopia.com, accessed
March 3, 2015.
http://photocornucopia.com/1059.html |
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