Shutter for barrel lenses?

[walter23]

If you want 1/500, the Speed Graphic is the way to go.

If you want the Speed Graphic shutter on the Tachihara, you will have to invent a way to cobble the two together!

Those damned iris mounts keep getting more and more expensive. I passed one up at like $50 on ebay once, and similarly neglected an old wooden camera beater with one attached for $200, and now I see 'em going in the hundreds.

 

[darkroom_rookie]

With a large shutter (e.g. Ilex #5), depending upon the size of the lens, you can mount the shutter in front of the lens (as mentioned by John), or the lens in front of the shutter with (typical packard mounting, except using a lensboard). Either mounting may vignet depending upon angle of view and format.

The advantage of front mounting the shutter is that if the filter threads are standard, you might be able to purchase filter thread adapters to mount the shutter onto multiple lenses. For mounting the lens in front of the shutter you will need to machine adapters for the different lenses to fit into the shutter.

So you can simply use cheap Chinese male-male macro reverse adapters? Are they strong enough to hold, say, a Copal #3 shutter? I'm toying with the idea of putting one in front of a Rodagon-G 210mm...

 

[Dan Fromm]

So you can simply use cheap Chinese male-male macro reverse adapters? Are they strong enough to hold, say, a Copal #3 shutter? I'm toying with the idea of putting one in front of a Rodagon-G 210mm...

View attachment 58786

Interesting idea. Not new, and it has never worked for me. But it is worth revisiting.

Lessee, now. Copal #3 mount thread is M61x0.75, not a standard filter thread. Still won't work.

But there are other ways. According to Rodenstock's Process Lens Manual the 210/5.6 Rodagon-G's front filter thread is M67x0.75. Its rear mounting thread is M72x1. Its entrance and exit pupils are around 38 mm in diameter at full aperture. Think about hanging the lens in front of an Ilex #3 or, if you have one, a Copal #3. www.skgrimes.com or www.srb-griturn.com can turn an adapter for you.

Most of my adapters come from Grimes, I have only one from SRB. The one from SRB does what I need but is on the light and flimsy side; they designed it with threading to meet my needs, their experience with filter step rings shows. My Grimes adapters are all much sturdier.

Re y'r sketch, its good practice to make the adapter's tube that screws into the shutter as long as possible. And y'r sketch shows rather thinner adapter walls than are really safe.

In general, I prefer mounting the lens in front of the shutter to mounting the shutter in front of the lens, if the shutter will bear the lens' weight and if the lens isn't so large that it blocks access to the shutter's controls. At the moment the shortest lens I hang in front of a shutter is a 60 and the longest is a 600. My 900 has a Compound #5 in front of it. I have a couple of 210s set up to mount in front of a #1. No inexpensive step or reversing rings involved, alas.

 

[darkroom_rookie]

Thanks for the info, Dan, appreciate it. This it shall be then:

 

[Alan Gales]

I own a Tachihara 4x5 and I wouldn't want to add any weight besides a lightweight lens to the front standard. My 8x10 lenses stress it.

I have read that some Shen Haos and Chaminox's may be made to take a Sinar shutter. I would look at a Chaminox.

As far as what Dan Fromm is telling you, I know Dan from Large Format Photography Forum and he is one of the local experts so I would definitely trust his opinion.

 

[Dan Fromm]

Not how I'd do it but it might work if you can get rings with the appropriate threads and if everything is very tight so that the rings are loaded only in tension.

 

[Mainecoonmaniac]

How about this?
http://www.youtube.com/watch?v=8odb2oeBrJA

 

[darkroom_rookie]

Not how I'd do it but it might work if you can get rings with the appropriate threads and if everything is very tight so that the rings are loaded only in tension.

Dan, the only way to mount Rodagon-G 210 M72 lens on Copal #3 seems to be screwing it to the shutter's front thread, which is recessed about 6 mm. I do have a high-quality M58-M72 0.75 step-up adapter with threads longer than those usually found on Chinese adapters. But it's outer diameter is larger than the front opening of #3 shutter and I'd need an approx. 10 mm M58 extension ring of comparable quality and thread length. The only such ring I know of is a really expensive Schneider extension tube for Unifoc system, and I don't know if the threads are long enough to have everything tight. Or did you perhaps have a totally different idea for mounting a M72 lens in front of a Copal #3?

 

[Dan Fromm]

If I wanted to do it right I'd pay a machine shop -- my machinist of choice is skgrimes, there are others -- to make a threaded stepped bushing. A male end to go into the shutter's front tube as the rear of a lens' front cell would, a female end to accept the lens' mounting threads.

If I wanted to do it wrong I'd look for T-mount extension tubes and try to bodge something up that would fit the shutter and accept a T-mount tube and that would fit the rear of the lens and screw into a T-mount tube. I don't know if the adapters needed exist. I've done similar with LTM tubes and custom adapters.

 

[darkroom_rookie]

Dan, not wanting to ruin either the lens or the shutter, I'll take your suggestion seriously and have an adapter such as this custom-machined:

 

[Dan Fromm]

That's the idea.

FYI, I have one fairly heavy lens in barrel that's held on a lens board by a stepped bushing. A retaining ring holds the bushing to the board, the front of the bushing has male threads that go into the barrel's internal rear threads; these look like filter threads but are in fact baffles to control stray light. I had Steve Grimes make the bushing that way because a cup-shaped bushing that accepted the lens' mounting threads would have been very expensive 'cos the mounting threads are around three inches forward from the end. Taking that approach with your Rodagon-G will make for a simpler bushing.

This brings up another point I've had to remind SKGrimes about from time to time. The bushing should be threaded internally, the threads like filter threads. You'll get much less flare that way than with a smooth interior.

Three thoughts about y'r sketch. The shutter end should go as deep into the shutter as possible, I'm not sure the bushing should butt up against the shutter's face plate, and there's no reason to make the bushing's walls as thin as possible. Stronger is better, you want something that is up to being stepped on. Not that I've ever dropped any of mine and stepped on them, but I sooner or later will. I've been spoiled; the shutters I use for front mounting are #1s, don't have conical face plates like the #3.

To contradict myself, now that I'm fully aware that the #3's face plate gets in the way putting the shutter in front of the lens might make life easier for the machinist. You'll still want a stepped bushing, but the step will be at 90 degrees.

Oh, and by the way, if you use an experienced photographer's machinist such as skgrimes explain the problem and explain how you'd solve it, then ask the machinist to propose what it sees as the best solution. The Dau brothers sometimes come up with solutions that are much better than mine.