Camera Design & Build

I have been using a 10 megapixel Sony R1, introduced back in September, 2005. It's been a great camera and I have gotten some good images with it. I used it during a trip to Cuba last summer and have recently edited 250 final images in anticipation of an exhibition of the work. Also in thinking about an exhibition, I was curious to know how large I could make an image and still have a reasonably high quality image for gallery viewing.

I have a Canon iPF8000, 44 inch, pigment inkjet printer. I did a test to see what the limits of size would be. I used a 44" roll of Museo Portfolio, 100% rag paper, and enlarged two images to about 26" x 36". While the images looked absolutely stunning from about 3 feet away, they will not tolerate closer inspection without showing artifacts of sharpening and general degradation.

So I thought that if I were to extend the series by returning to Cuba, what camera would I bring to improve the work. I want to have the quality of large format camera work. I thought a digital direction using something like a Phase One back on a Hasselblad, but what a bother that would be: camera, tripod, tethered laptop, darkcloth, portable table for the laptop. The expense/risk of the equipment would be very high even if I could get my hands on it. This would be as much trouble as using an 8 x 10 view camera and film.

Then I had a great insight: why not use the 4 x 5 film format? Normally this would be almost as much trouble as the 8 x 10, but with less expense. There's still the tripod and all the set up required. But what if the camera could be hand held? AHA! News photographers in the 1940's typically used the Speed Graphic camera handheld. I happened to have a Speed Graphic, and also some very high quality Schneider lenses that I used for architectural work. I would not have the perspective control advantages of a view camera on a tripod, but I could make all those corrections on the computer.
I got the Speed Graphic out for consideration and realized what a heavy camera it is: five pounds without a lens. I then realized that all I need for the project is a fixed focus box camera with one or two lenses. So I decided to build such a camera using some cedar panelling we once used to mothproof a closet.

I took measurements from the Speed Graphic to start to outline the general shape of the box, size of the filmholder, etc. Since the type of photography I plan to do with this camera is frontal architectural imaging, I decided to build the camera around two wide angle lenses, a 90mm and a 120mm. I decided to make the camera box as small as possible and change the focal distance by mounting each lens on an attachable lens board that would be sized so that the lens was fix focused on approximately the hyperfocal distance: the distance between the lens and the closest object that is in focus when the lens is focused at infinity. When focused at this distance everything will appear in focus from half the hyperfocal distance to infinity, a formula I am sure was employed in early box camera design.

Armed with my diagrams and general direction, I got the cedar panelling out and started to craft the shape of the box using a chop saw, corner clamp used for framing and some woodworking glue. I confess that the first box I made was cut and glued incorrectly and I had to repeat the steps; usually my working method. (I know, measure twice, cut once--but I do!)

Gradually the box began to take shape. On my work table a mounted lens can be seen, along with the ground glass/film holder that I borrowed from the Speed Graphic, and some of the sophisticated tools I used for the project. (Hammer?)

From the front porch of my workshop I set up an "optical bench" and subject. The 90mm lens mounted on its lensboard was pointed toward the subject on the right. The white focus card was positioned until the components of the image (the cylinder and the tree behind) were clearly in focus. Then the depth of the lens board was adjusted with the camera interface to maintain that lens to film distance. If all this looks terribly crude, it was.

The camera is starting to take shape. The lensboard is attached with two machine screws, one on each side, and the hooded ground glass focus is raised in back.

Here's the finished camera with grip, cable release and sports finder. The shutters I use for my lenses are "press" shutters which are self-cocking. In earlier architectural work I found the need for multiple exposures but did not want to manually re-cock the shutter and risk moving the camera even slightly. I discovered the "press" shutter and switched. (See the story on Baroque for another innovative photography technique.)


I anticipate the following working method: find a subject, choose and mount the lens, set the shutter for 1/125th sec and the aperture at f/16, install the film holder, draw the darkslide, point and shoot, replace the slide. I will be using Fuji 160 ISO daylight color negative film and the rule of 16s for exposure (shutter is 1/ISO @ f/16).

OK, I'll have a small light meter with me to confirm exposures. But think about it, most of the exterior architectural subjects are covered with this method. It's simply move to the next subject and repeat. Each effort will produce a well-exposed, sharp, large format color image suitable for scanning and printing. And with a minimum of weight and maximum of convenience. And the weight of the camera: 21 oz. compared to 5 lbs for the Speed.

Now for some field tests. (See January 28 posting here.)
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June 29, 2008

I haven't had a chance to test the camera yet, but we did make a trip to the Vancouver area of Canada, a country that does not share the U.S. trade embargo with Cuba. There were several cigar stores that advertised "Cuban Cigars" and we were able to acquire an empty Cohiba cigar box. Since my original intention for the construction of the camera was to improve the resolution of photography I might do on a return trip to Cuba, I thought it was an interesting coincidence that the cigar box is almost a match to my camera design!