Technical Notes: V38-Mount System

What’s a v-mount? If you aren’t familiar with v-mount, Schneider-Kreuznach makes the most popular and widely used v-mount system on the market today, the V38-Mount System. The system locks two units each with male and female v-mounts using three set screws that engage and lock into a V-groove. This groove and set screw mate to secure and align the two v-mount units. This works surprisingly well.

A couple of weeks ago I received a v-mount machine vision sysem and on this system I found something really interesting. I’ve never heard of or read this anywhere. The V38-Mount System was damaged in shipping at one of the male v-mounts so only one component broke in the system. In my case this was a 10mm V38 extension tube at the male flange.

These diagrams indicates the points of failure on a 10mm V38 extension tube. You can see the damage to the male v-mount flange and the deformed v-groove edge.

In this case the optical assemyby was damaged in shipping and judging by the two set screws that broke free, you can see the direction of the force that caused the v-mount to fail.

The v-mount break away design is genius. The break away feature will save you from multiple damaged system components. This 10mm extension tube was the cheapest part in the system and is the ideal place for any damage.

Questions of comments? Just send me a message.

New RAF Camera mount Adapters March 2023

Four new RafCamera adapters have just arrived in the office. These designs are all custom made for our requirements. These are all threaded cylinder clamp type adapters. I prefer this type of adapter over the ring type since the long threaded area makes setting focus or magnification easy. Since there are threads on the front and rear end you, mounting the lens in the opposite direction takes seconds. Also mounting a lens hood using a extension tube mounted at the front is also possible with threaded cylinder adapters.

Polaroid SprintScan 4000 scanner lens mount adapter
21mm ø clamp to SM1 male threads 29mm total length
Clamp style step-down adapter with a full-length threaded body
Adapter tested March 24th 2023
RafCamera link: https://rafcamera.com/clamp-21mm-to-sm1m

Polaroid SprintScan 120 scanner lens mount adapter
30mm ø clamp to M42 x 1mm male threads and 40mm total length
Clamp style step-down adapter with a full-length threaded body
Adapter tested March 24th 2023
RafCamera link: https://rafcamera.com/clamp-30mm-to-m42x1m-40mm

Lasergraphics 50mm f/3.5 High MTF scanner lens mount adapter
43.2mm ø clamp to SM2 male threads, 43mm total length
Clamp style step-down adapter with a full-length threaded body
Adapter tested March 24th 2023
RafCamera link: https://rafcamera.com/clamp-43-2mm-to-sm2m

Plustek OpticFilm 120 scanner lens mount adapter
47.5mm ø clamp to SM2 male threads, 40mm total length
Clamp style step-down adapter with a threaded body
Adapter tested March 24th 2023
RafCamera link: https://rafcamera.com/clamp-47-5mm-to-sm2m

This shipment arrived from RafCamera in Belarus in about 20 days via priority mail Belpost to USPS to us.

You can find these RafCamera products here: https://rafcamera.com/

Closeuphotography.com does not make a commission on any links on this site. This information is being shared to help our friends and colleagues and not for profit.

Admon 918 Industrial Lens Update

We have been able to test the 918 Admon lens and unfortunately the lens is definitely not optimized for the visible light spectrum. The sample images below were made with the 918 on a Sony Sony a7R IV camera at 1.55x where the lens exhibits strong pink and green chromatic aberrations. Out of focus CAs are even more pronounced. What a shame since the lens is sharp at f/2.8 and it was able to cover the entire a7R IV sensor.

Line scan cameras can be designed for use in the visible spectrum from 400 – 700 nm but there are machine vision systems are are optimized for other spectrum ranges like UV, NIR and SWIR. The wavelengths of visible light are relatively short for blue and violet (short wavelengths) and longer for red and orange (long wavelengths). When a lens is used outside its designed wavelength range, the lower the resolution and the higher the chromatic aberrations.

The Admon 918 lens could technically be designed for use at 918 nm which would be a near infrared wavelength. FYI, I have also seen 077, 604, and 732, Admon models for sale in China. There could be other types of Admon lenses out there made for visible light but I cannot find any company information online.

For some good information on line scan lenses and wavelength ranges see this page on the VST lens site:

https://vst.co.jp/en/support/lighting/

This Just in: Admon 918 Industrial Inspection Lens

This is the Admon 918 105mm f/2.8 industrial lens, other than name, focal length and aperture that’s the extent of what we know about this lens. This lens came from a seller in South Korea for the absurd price of $25 (lens only). There is no information on this lens available online and the focal length and f-stop are measured. The construction and fast aperture make the lens look like a high performance optic but I really have no idea to be honest, the lens might not even be corrected for visible light for all we know.

These 3 photos from the eBay seller’s ad, sorry for the poor quality, are interesting. Judging by the extension, about 150mm, it looks like the 918 lens is being used about 1.5x and reverse mounted, with the camera on the far left set for higher magnification. Also the line scan camera sensor is shown in one of the images and it looks like the line scan sensor is right about 43mm wide. So the 918 lens should cover a full frame area sensor.

Name: Admon
FL: 105mm (measured)
Fixed aperture: f/2.8 (measured)
Aperture in reverse: f/3.3 (measured)
87mm x 49mm
No accessory or mounting threads
Wavelength range: unknown
Source: unknown country (this copy came from a South Korean source)

I’ll create a page for this lens once I am able to make time to test it. If you have any information on these lenses please send me a message. Thanks.

February 2023 Equipment and Testing Updates

MGI Melles Griot Oxberry Cine Film Recorder Lens

New Lenses:

MGI Melles Griot f/4 film recorder lens
Notes: Arriving this week.

MGI Melles Griot Oxberry Cine Film Recorder Lens
Notes: Arriving this week.

Lasergraphics High MTF lens Type 715-027
Notes: Arriving this week. This is a new MTF lens

New Pages:

Plustek OpticFilm 8100 Lens Test
https://www.closeuphotography.com/plustek-opticfilm-8100-scanner-lens-test
Note: 90% finished.

New Test Page in Progress:

50mm Lens Test 2023

  • Beseler HD 50mm f/2.8

  • Lasergraphics High-MTF 50mm f/3.7 scanner lens

  • Leitz Wetzlar Photar 50mm f/4 (version II)macro Lens

  • Linos Rodagon 50mm f/2.8

  • Rodenstock Rodagon 50mm f/2.8

  • Rodenstock Rodagon-P 50mm f/2.8 lens

  • Rodenstock APO-Rodagon-N 50mm f/2.8 lens

  • Schneider APO Componon 45mm f/4 Macro Iris Line Scan Lens

  • Schneider Componon-S 50mm f/2.8 Macro Iris Line Scan Lens

  • Schneider Componon-S 50mm f/4 fixed aperture Lens

  • Schneider M-Componon 50mm f/4 Macro Lens

  • Tominon E36 MC 48mm f4 Printing lens

  • Tominon 50mm f/4.5 macro lens

https://www.closeuphotography.com/50mm-lens-test-2023
Notes: all shooting and image processing finished. Some surprising results.

Pages in Progress:

Polaroid-SprintScan 120 Scanner Lens page
https://www.closeuphotography.com/polaroid-120-scanner-lens
Note: 90% finished

Nikon LS-3510 AF scanner lens page
https://www.closeuphotography.com/nikon-ls3510-film-scanner-test
Notes: 90% finished

Lasergraphics High MTF Scanner lens page
https://www.closeuphotography.com/lasergraphics-50mm-high-mtf-lens
Note: 95% finished.

Printing-Nikkor 1x Test: Ultimate Edition

  • Nikon Printing-Nikkor 150mm F2.8 Float Ring

  • Nikon Printing-Nikkor 150mm F2.8 Early

  • Nikon Printing-Nikkor 150mm F2.8 IMAX

  • Nikon Printing-Nikkor 105mm F2.8

  • Nikon Printing-Nikkor 105mm F2.8A

Note: Total of eight PN lenses! Shooting complete

Makro-Symmar 5.6/180 lens page
https://www.closeuphotography.com/makro-symmar-180
Note: 90% finished.

Moritex F90C lens page
https://www.closeuphotography.com/moritex-f90c-lens-test
Note: page started

Sigma 105 Art Macro lens page
https://www.closeuphotography.com/sigma-art-105-lens-test
Note: lens is in the office

Laowa 100mm 2x APO lens page
https://www.closeuphotography.com/laowa-100mm-2x
Note: lens is in the office

Rayfact MJ90 4/90 0.05x - 0.5x line scan lens page
Note: lens is in the office