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View Full Version : Got a 19" RDA(in barrel) to mount, but have some questions 1st



Daniel Stone
29-Apr-2011, 15:09
hey guys(and gals :)),

I'm wondering if a 19" RD Artar will be able to mount into a Copal #1 shutter, even if it loses a stop or two.

my main two concerns regarding this is:

1. To save space. Since Copal 3 shutters are kinda big(especially seeing that I'm using Technika boards w/ an adapter plate on my 8X10), I'd like to keep the lenses smaller, to take up less room in my backpack(Kelty Redwing). My Graphic-Kowa is in a #1 sized shutter, and hopefully I can fit this lens into one as well? I might just get the Fuji-C 450mm if it can't. I owned one before, and loved it. Stupid me, I sold it...

2. Loss of coverage? By using a smaller shutter, would this affect the covering power of the lens, even when "wide open"? Just wondering. I'm not optical expert here, but having just sold my 450mm Nikkor-M(which was a great lens btw), but I know most people have the 19" RDA mounted in a Copal #3, or an Ilex #4/5.

Just wondering. Also, SKGrimes I know can do the work, I've used them before. They do great work. However, is there anyone here on the site that could/would do it cheaper by chance? I'm able to operate an 3-axis mill, but precision turning/threading scares the sh!t out of me :p. I don't need to have the SKG logo emblazened on my stuff, just have it done accurately and precisely. I'd supply the Copal #1/(or 3 if a #1 won't work) and such...

thanks!

-Dan

E. von Hoegh
29-Apr-2011, 15:29
I don't know about the shutter; I'm at a ladyfriends computer and she doesn't have a Copal 1 handy to measure.
If you have the lens in a barrel, any competent machinist can turn a set of mounting rings that will duplicate the original spacing and location of aperture.

Mark Sampson
29-Apr-2011, 15:40
Assuming that you could fit a 19" Artar into a #1 shutter you would lose speed, not wide-open coverage. But I'm sure your lens is physically too big to fit in a #1 shutter. There's an extensive chart on the Grimes site that explains what fits into what, no doubt compiled through experience. Kerry Thalmann has on his site a series of recommendations about compact lenses for backpacking; I'd refer to that too.
An analogy: I once saw a 'motorcycle' that had been built around the V-10 engine from a Dodge Viper. Impressive engineering, but I'm pretty sure that no one actually rode the thing.

Daniel Stone
29-Apr-2011, 16:59
Mark:

good comparison :). I've seen pictures of that "bike" w/ 12in-wide tires :).

I guess its time to look for a 450C fujinon!

this won't just be for 8x10 work, but for a 6x17 convertible camera I'm going to build a "conversion" set of bellows/lensboard adapter for(Gaoersi camera)

so I'm looking to go as light as possible...

-Dan