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DaveSmith
7-May-2020, 14:19
Hi All

I have the Congo 250mm f4.5 lens in a barrel, I was hoping to fit it in a Shanel 5 B-S shutter, but it doesn't fit that shutter. Does anyone know which shutter it will fit (if any?). I am intending to use this on 10x8, which I think it just about covers?

Many thanks for any help

Dave Smith

Maris Rusis
7-May-2020, 18:06
My old catalogue for "Congo" Studio Lenses in Normal Barrel lists your lens. Specifications are:

Focal length 250mm
Aperture f4.5 to f64
Format intended 6 1/2" X 8 1/2"
Angle of view 54 degrees
Circle of image coverage at f16 is 270mm
Front lens mount diameter 70mm
Rear lens mount diameter 70mm
Overall length 63mm
Distance from lens seat to film plane 230mm
Back focal length 219.2mm
Filter size 67mm
Size of roller blind shutter required: diameter 2 3/4"
Weight 535g

Yamasaki never offered this lens with a shutter. The nearest they made was a 250mm f4.7 using the same lens elements with the cells mounted in a Copal #3 shutter. The maximum iris opening for a Copal#3 shutter is 45mm hence the reduced maximum aperture. Recovering the lens elements from the 250mm f4.5, buying a Copal #3 shutter, and fitting all the components together would be an exquisite piece of optical engineering ... $$$$. Good luck!

B.S.Kumar
8-May-2020, 00:23
The Congo 250mm f/4.5 barrel lens is probably the same size as the Fujinar 250mm f/4.5 lens. All the Fujinar barrel lenses - 180mm, 210mm, 250mm and 300mm - can be mounted in a Shanel 5A shutter with an appropriate adapter. The adapters for the 250mm and 300mm lenses are cup shaped, as shown front left in this photo:

https://i.postimg.cc/q78NQfM7/Fujinar30cmf4-5-Shanel5-AShutter-01.jpg

Kumar

Vaughan
30-Mar-2021, 04:08
Hello Kumar, I am looking for the adaptor ring to mount the Fujinar 250mm (25cm) f4.5 barrel lens onto a Shanel 5A shutter. Your post above included an image of the adaptor kings, however that image is longer available. Do you have any of the rings? Thanks.

Dan Fromm
30-Mar-2021, 05:59
Vaughan, if you have the money skgrimes has the time.

Bernice Loui
30-Mar-2021, 10:44
Or, use with Sinar Shutter or similar shutter.


Bernice

Vaughan
30-Mar-2021, 17:46
Or, use with Sinar Shutter or similar shutter.


Bernice

I have a Rittreck View with 4x5 and 5x7 backs, and a Shanel 5A shutter. I was hoping to have the one shutter to use with the barrel Fujinar 180mm and 250mm lenses to save weight.