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Novoflex 400mm f/5.6 T-Noflexar

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#1 UlfW

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Posted 12 April 2021 - 12:13

Last Update: 03 April 2021 agb/label
Finalized: Work in progress.

Novoflex 400mm f/5.6 T-Noflexar

Manufacturer: Novoflex. The achromat might be made by Rodenstock
Lens Label: ( NOVOFLEX ) T-NOFLEXAR 1:5,6 f=400mm <serial number>
Currently manufactured: No
Lens type: Manual focus, Extreme tele lens, true long focal design?
Design: Achromat, 3 elements in 2 groups
Focal length: 400 mm
Aperture range: f/5.6 – f/32, Manual, 24 blades
Sensor format/coverage: 24 mm x 36 mm. Lens head covers more when mounted in suitable mechanical structures. Was designed for middle-format?
Mount: * via a focussing bellows, BAL-U, with a suitable lens mount adapter part.
There are mount adapters for many different camera types.
Alternatively.
There are rigid spacer tubes ending with mounts for different cameras.
However they give a very bad minimum focus distance.
Helicoid: No, Focussing with a bellow at the rear of the lens.
Front filter: 75 mm x 0.75 mm
Introduction year: ca mid 1980?
S/N of test object: 40817

* A document showing different configurations and mount options for Novoflex lenses present when the document was written:
https://www.pacificr...00070/00070.pdf
There are more modern adapters for bellows and Schnellschuss-lenses, including the CANA-AF for Canon EOS


Image of test object:

The long lens head to the right of the bottom row, marked "f = 400 mm":
Posted Image

Here mounted in a Schnellschuss handle/lens tube:
Posted Image
There is an accessory (PISTAR), that clamps around the ticker part of the lens tube directly behind the aperture control ring. (I do not have a PISTAR to show)
That improves the balance considerably, improving the stability. The mounting hole I used in this picture is intended for a shoulder support making the lens looking even more like a weapon.

More information about these lenses in this post:
https://www.ultravio...dpost__p__25241

This lens structure is of the same generation as the Schnellschuss fast focussing lenses seen in the last image in above link.

Transmittance Summary

Definitions of the parameters below
  • Range: The NOFLEXAR 1:5,6 f=400mm transmits 1-81% in an increasing slope from 319nm to 400nm.
  • TVISmax (%) = 93%
  • T400nm (%) = 81%
  • T365nm (%) = 70%
    This high percentage is an indicator for quite short exposure time under typical UV-pass filtration peaking around 360 nm or when using 365 nm UV-LED illumination.
  • λUV HMvis(nm) = 344nm
  • λUV HM400(nm) = 341nm
  • λUV Zero(nm) = 319nm
  • These three values indicate that the lens is working even for some upper UV-B photography with some filters and a few for this, suitable cameras.

Spectral Transmission Graphs

UV-NIR, Novoflex T-NOFLEXAR 1:5,6 f=400mm
Attached Image: Screen Shot 2021-03-20 at 06.56.38.png
The transmission measurement accuracy into the end of NIR range is less good due to limitations in the light source.

UV, Novoflex T-NOFLEXAR 1:5,6 f=400mm
Attached Image: Screen Shot 2021-03-20 at 06.55.32.png

UV-Log, T-NOFLEXAR 1:5,6 f=400mm
Attached Image: Screen Shot 2021-03-20 at 06.55.03.png
Numerical Spectra Data available: Yes


Filters and how to use them on this lens:
The front filter thread is an unusual 75 mm 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.

An alternative, is to putty-mount a filter directly inside the lens. There are several flat surfaces that likely would work to mount a filter or a step ring fitting the filter.

Versions compatibility:
The Lens-heads of this generation share the mounting thread dimension and are interchangeable between the older Type-B and next generation Type-C, of Schnellschuss-lenses.
The last generation, the Type-D of Schnellschuss-lenses have a special new type of bayonet mount for the lens heads.


Handling and focussing:
Difficult due to the long focal length.
A stable tripod, or two, are needed to support the lens.

Flare and sun-stars:
TBD

Sharpness:
High for the age of the lens.

Lens distortion:
TBD

Chromatic Aberration in UV:
TBD

Edited by UlfW, 16 June 2021 - 13:27.

Ulf Wilhelmson
Curious and trying to see the invisible.

#2 dabateman

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Posted 12 April 2021 - 12:44

Wow $255 in maybe 1969 if I read that correctly. Didn't that also buy you a car back then. Expensive system. I wonder if this is what Leica copied for their R mount system.

#3 Stefano

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Posted 12 April 2021 - 12:53

A general question: has the reference/template topic disappeared? I can't find it and if I click on the link in the Transmittance Summary paragraph I have this error:

"[#103137] You do not have permission to view this topic."

I am logged-in of course.

Edited by Stefano, 12 April 2021 - 12:53.


#4 UlfW

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Posted 12 April 2021 - 15:39

I have no idea where it has gone!!
I hope it gets restored.
Ulf Wilhelmson
Curious and trying to see the invisible.

#5 UlfW

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Posted 12 April 2021 - 15:49

View Postdabateman, on 12 April 2021 - 12:44, said:

Wow $255 in maybe 1969 if I read that correctly. Didn't that also buy you a car back then. Expensive system. I wonder if this is what Leica copied for their R mount system.
It was considered a high end system, used in extreme environments by professional nature photographers.
The focussing method with a spring-loaded squeeze system is both fast and reliable. In really cold weather helicoid based focusing stuck when the lubrication solidified.
The physically long Novoflexars got a kind of inertia based stabilisation, just like a line-dancers pole. The long mirror lenses are the complete opposite in that aspect.

There was one or two alternative lens heads from Leitz.
The Leitz Telyt 6.8 / 560 was available in this system and possibly one longer lens.
That Telyt 6.8 / 560 do not have a good UV-reach.

Edited by UlfW, 12 April 2021 - 15:52.

Ulf Wilhelmson
Curious and trying to see the invisible.

#6 UlfW

    Ulf W

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Posted 16 June 2021 - 13:08

Updated the top document with pictures.

Edited by UlfW, 16 June 2021 - 13:10.

Ulf Wilhelmson
Curious and trying to see the invisible.