Adapting a shutter?

[Toffle]

I have a Wollensak Rapax shutter that fits a Copal #0 lensboard and a Staeble Magnogon process lens (which also fits a Copal #0 board) that I would like to mount in the shutter. Unfortunately, apart from the diameter of the real mounting flange, there does not appear to be any compatibility between the pieces. The front and rear inside threads on the Rapax are 31.6 mm. The mounting ring on the shutter is listed at 33.45 mm. The ring on the lens appears to be the same size but with a different thread. I don't have proper measuring tools, so I can't be more precise than that.

My first thought is that being a process lens, it may be incompatible with my purpose of mounting it in a LF camera and shutter. I most likely am better off simply investing in a new lens, and certainly better served by a lens which is is properly matched to its shutter.

That being said, does anyone know of a workable solution to matching this lens and shutter combination?

Cheers,

 

[archphoto]

Process lenses have been used for LF photo's before.
Whether you can use your lens greatly depends on its focal lentgh and image circle.

Fitting this lens into the shutter: is the lens too big or too small for the shutter ???
How good is it ?
If you can put this lens on a board and focus your camera at infinity, how sharp is it in the center and the corners ?

This type of lens is used with a Sinar behind the lens shutter: so which camera do you have ?

Greetings,
Peter

 

[Toffle]

Process lenses have been used for LF photo's before.
Whether you can use your lens greatly depends on its focal lentgh and image circle.

Fitting this lens into the shutter: is the lens too big or too small for the shutter ???
How good is it ?
If you can put this lens on a board and focus your camera at infinity, how sharp is it in the center and the corners ?

This type of lens is used with a Sinar behind the lens shutter: so which camera do you have ?

Greetings,
Peter

Hi Peter,
To begin with, the lens is too big for the shutter... about 2mm as near as I can tell. The last 1/2" of the lens mount is bare of threads, so that may pose a further difficulty.

I have achieved quite reasonable sharpness at all points of the image circle, but my experience with this sort of thing is very limited, having only had my camera, a Calumet 400c a very short while..

That's all I have at the moment. I don't have any way to make fine measurements, so I can't be more precise.

Cheers,

 

[Toffle]

Does anyone know if the front ring on the Rapax (the 31.5mm retaining/mounting ring) can be safely removed from the shutter? The larger, polished metal ring that holds it has indentations for tools, but I'm more interested in removing just the center ring. This might give me enough diameter to mount the lens directly on the front of the shutter.

Cheers,

 

[removed account4]

hi tom

have you considered
mounting the lens to the shutter
as if the shutter was a packard shutter ?
( or use a packard shutter (unfortunately 1 shutter speed) instead of the wolly )

i mean ... keep the lens in the barrel and just front mount
or rear mount the lens to the shutter ..
maybe with a step up /down sort of ring or
some sort of threaded pipe/fitting ?

maybe this won't work because the diameter of the shutter
is smaller than the fstops you hope to use on the lens ...


good luck!
john

 

[Toffle]

hi tom

have you considered
mounting the lens to the shutter
as if the shutter was a packard shutter ?
( or use a packard shutter (unfortunately 1 shutter speed) instead of the wolly )

i mean ... keep the lens in the barrel and just front mount
or rear mount the lens to the shutter ..
maybe with a step up /down sort of ring or
some sort of threaded pipe/fitting ?

maybe this won't work because the diameter of the shutter
is smaller than the fstops you hope to use on the lens ...


good luck!
john

Hi John,

Yes, I have considered both front and rear mounting of the shutter, and any workable arrangement of step rings. I am hoping whatever solution I use will not add too much depth to the assembly as this lens (a 105mm process lens) allows very little bellows draw as it is. Even at that, I have had to use a recessed plate to allow enough movements for anything more than simple architecture shots.

I am seriously considering packing this shutter away for the time being and building a couple of Galli Shutters. The Wollensak is a nice piece of work, but I really just want to take pictures.

Cheers,

 

[Toffle]

Well, my solution came at the price of $1.42 in the plumbing aisle of the hardware store. On Saturdays, you're likely to find all manner of folks wandering the hardware stores, looking for odd bits of stuff to make their projects come to life. (they call it "McGuyvering" )A simple 1 1/2' to 1 1/4 reducing coupler, shortened and ground to size. It's workable right now and with a little fiddling I should be able to match the parts more precisely. All in all, I'm quite pleased.

Cheers,

 

[jimgalli]

Rapax is US thread. Staeble Ultragon is metric. Not an easy marriage.

 

[Toffle]

Rapax is US thread. Staeble Ultragon is metric. Not an easy marriage.

The thread issue kind of works itself out, as the plumbing fittings are pvc and will thread themselves once you get them started. Right now, the larger problem is that there is some quite noticeable vignetting with the lens stuck on an adapter stuck on the front of the shutter. This arrangement does not allow the lens to cover 4x5, and it most certainly means I will have to recalculate my apertures if I decide to go with this setup.

All I wanted was to add a shutter to my (only) LF lens. I just made the move to LF, and I was hoping to fit a shutter without adding too much cost to my kit. Looks like I might be using a Galli shutter until I can scrape together enough cash to do it properly. (trying to do things on the cheap is never the best solution anyway)

Cheers,

 

[Nick Zentena]

You've got the 105mm? F/5.6 I guess. Wide lenses aren't the easiest first lens for LF. You're likely best off picking up a cheap 150mm or 210mm.

I'd save the 105mm for the enlarger.