Compound / Dogmar update

I wrote recently of my discovery of a wonderful old Dogmar lens and Compound shutter, attached to a vintage 8 x 10 inch view camera given us by my wife’s father. Well, it turns out that there may be some life left in that old kit yet.

Recall that I had looked it over briefly when we first got it, and decided that it would not do for making photographs itself, so we put it aside. My wife got it out to use as a decorative object, and it was then that I started wondering if just the lens—with or without its original shutter—might be of some use. With the assistance of the experts over at the Analog Photography Users Group I was, within hours, able to identify camera, shutter, and lens; and to find out that I might have a diamond in the rough on my hands. My next step was to send the shutter and lens off to S.K. Grimes for a look-see, to find out if it would be feasible to put these old tools back to work. Grimes has weighed in; more on that in a moment.

As a momentary digression, I offer this primer on view-camera construction. Feel free to skip this indented section if you already know this stuff. View cameras consist of a lens assembly at the front; a flat sheet of translucent groundglass at the rear upon which the image is focused; and a flexible accordion-like bellows connecting the two. Light rays reflected from the subject enter the lens and form an image that appears on the groundglass; focusing is accomplished by fine adjustment of the distance between lens and groundglass. For the exposure, a sheet of film in a holder is placed in a slot front of the groundglass, with the film lying precisely in the plane of sharp focus. The shutter is triggered to admit a brief flash of light, exposing the film. Develop it, and you’ve got a picture. View cameras are the oldest and simplest camera design; they are the archetype of all subsequent still cameras. Even the most modern professional digital camera is simply a highly-refined descendant of this original design.

In our current tale, the lens assembly is the where the action is. View-camera lenses and shutters are mated to each other and to a flat rectangle of wood, metal, or carbon fiber material, the lensboard. Shutters, including my old Compound, are typically donut-shaped, with the ring containing the mechanical guts of the shutter. The lensboard also has a hole the same size as the shutter ring’s central hole; a flange on the shutter goes through the lensboard hole; a retaining ring screws onto the flange to pinch shutter and board together tightly.

So what’s the hole for? The lens itself, of course. The shutter ring’s inner circumference is threaded to accept lens components in metal tubes; these screw into the shutter like bolts into a nut, from both directions, front and back—depending on the focal length and configuration of the specific lens in question. To interchange lenses, you simply remove the board/shutter/lens  assembly from its attachments at the front of the bellows, and pop in a new one with the desired lens. It follows, then, that each lens must have its own board and shutter. (By contrast, a modern digital SLR’s shutter is of a different configuration and is integral to the camera body; only the tube containing the lens elements is removable.)

Back to SK Grimes. Adam there looked over my gear and determined that the old Compound shutter would need a CLA (“clean, lube, adjust”) and maybe some basic repairs, but could be brought back into service with relative ease. The lens itself would need only a decent cleaning. The only real challenge would be to adapt these components to my intended camera, a Chamonix 45n-1, only yesterday arrived from the People’s Republic of China. We would have to somehow fit the existing shutter and lens into a Chamonix-compatible lensboard; or mount only the lens into a modern shutter that will fit on the board. The Chamonix is a small, compact camera that uses a smaller board than the old camera; modern shutters and lenses are quite a bit smaller than their ancestors (like my Compound and Dogmar). Essentially, size of components and their cost and availability would determine how we’d proceed.

Honestly, when I first started on this project, my idea was simply to remount the lens into a modern Copal or Compur shutter and forget about the old Compound, sentiment and authenticity aside. A modern shutter would have several advantages: wider range of shutter speeds; more robust construction; ease of maintenance and availability of spare parts and service; and the ability to automatically trigger and synchronize studio flash gear with the shutter, for which there is no provision with the old Compound. Modern shutters are standardized by diameter, with sizes 0, 1, and 3 (don’t ask me what became of 2) readily available in ascending order of diameter (and thus, diameter of lens components that will fit.) Anything up to a Copal #3 would fit onto the Chamonix board with ease; unfortunately, the old Dogmar lens is so large that it would take an old #4 or #5 shutter (no longer made) of uncertain availability and cost to hold it. Such a large shutter would not fit the relatively small Chamonix board. The existing Compound shutter could, however, be made to fit the board. So that decided it.

I’ll report back when the lens and shutter return from Grimes.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s