Mechanical Shutter Experiments

Earlier this week I created another photography video, this time about the experimental shutter I built, some years ago, for the 8" x 10" box camera.

The genesis of this project was having used paper negatives in improvised lens cameras and finding that, due to the speed of the paper (I rate Freestyle Photo's Arista grade 2 RC paper at an exposure index of 12), I'd have to stop down the lens to a very small (2-3mm) aperture, in order to make the shutter speed long enough (>1 second) to accurately and repeatedly time by a hand-operated shutter, in bright daylight landscape conditions.

Under dimmer kinds of light, like window light, I've made a number of satisfying indoor still-life exposures in the daytime, where these improvised lenses, operating at wider apertures, display some interesting optical effects that make the resulting images rather special. But under bright daylight they have to be stopped down so much, in order for their exposures to be timed by hand, that they come to resemble hybrid pinhole/lens optics, lacking those optical aberrations I've come to appreciate from adapted optics, like binocular objectives and meniscus lenses.

So it seemed that I'd need some kind of shutter mechanism. But how?

I spent a long time cogitating about simple mechanical shutters, and ended up making a series of proof-of-concept sketches over several years, trying to find some design that might prove workable. In the end, I felt that I just had to start building something, and so it became a design-as-you-build kind of project, using scrap bits of hardware I'd collected over the years; my motto being something along the lines of never throw anything away, you might use it someday.

What I was trying for was a shutter whose speed could be varied over some practical speed range, to account for differences in exposure. Many of the early designs I considered were simple slit shutters, operated by spring tension and moving either horizontally or vertically, with the width of the slit accounting for the variation in exposure. But I soon realized that with a fixed spring tension a variable slit shutter operating up front at the lens would only yield a small range of speed variations.

After some time I realized that I could make the traveling slit camera into a rotary blade camera, and by altering the angle between the blades the timing could be adjusted. However, my initial idea was much more grand: by slowing down the speed of rotation, I could have a wider range of speeds, from multi-seconds long to fractions of a second, perfect for paper negative media.


But I never got far enough along with this design to build a practical mechanism for slowing down the rotation while making its speed reliable and repeatable. The one big idea I had for this was based on a mechanism I'd seen years earlier, while repairing a Technics audio cassette deck, which was the method used to dampen the speed of the cassette door when it was ejected. Most cassette players used a simple plastic dash-pot mechanism, a piston and cylinder, with an o-ring and some grease, so that as the spring tension tries to slam the door open, the air in the piston is released in a controlled fashion through a small opening, allowing instead the door to slowly and smoothly open. The problem with this design is when the grease hardens up over time, and the cassette door slams open uncontrollably.

Panasonic's method was different. They used a small brass whirligig, a 4-vane rotating piece that was driven to rotate by a drawstring band attached to the door mechanism. As the spring tries to forcefully slam open the door, the band rapidly spins the whirligig, the resulting air pressure slowing down and regulating the speed of the door into a smooth motion. The best part of this design was its reliability, as there were no lubricants to harden over the years.

So my idea for the shutter was to employ this whirligig mechanism, in a small but rapidly turning pulley with vanes, that the shutter cord would spin as the shutter was moving, helping to keep the speed constant. In theory, it sounds plausible; but I never got to the point of implementing it with this shutter.

As you note from the video, the problem with this shutter is that the three speed adjustments, that alter the angle between the blades, don't really offer much variation in speed; and there's too much friction in the mechanism, caused by the way I designed for compensating for light leaks.

The sad thing about this project is that it's sat dormant for some years, as I just couldn't find the motivation to get back to improving it. But now, with these You Tube videos and this blog, perhaps I've painted myself into a corner whereby now I'm forcing myself to get back and finish these projects. And that's a good thing.

Here is a detailed photo of the shutter with the parts labelled, made a few years back; note that I've more recently changed the draw cord from a thin black to thick white cord.


This video was the first of two parts; next week I hope to take the camera out, with shutter attached, and make some usable images. Stay tuned.

Pueblo Bonito, Chaco Canyon

I first became aware of Chaco Canyon from the PBS documentary "The Sun Dagger," narrated by actor Robert Redford, from back in 1982, and since then have made a handful of day trips to this National Historic Park and UNESCO World Heritage Site.

Despite it being relatively well-known, and managed by the United States National Park Service, Chaco Canyon is located in a desolate part of northwestern New Mexico, requiring the lengthy traversing of dirt roads to gain access, which can be treacherous in inclement weather. Yet I've made the trek a handful of times over the last 30 years, and always came away from the experience with a renewed sense of appreciation for the native peoples who managed to build these structures, over a millennium ago, with their high walls of stone and alignment to the celestial sphere, far from the relative conveniences of their home settlements, where finding sources of food and even fresh water would be a challenge.

There is evidence that, over the centuries, thousands of people traveled tremendous distances to spend time here at Chaco, for what purpose we are not entirely certain, perhaps ceremonial; but archaeological evidence suggests visitors came from as far away as central Mexico. I get this sense of a connection with the past when I stop to consider that I, too, am one of those many visitors, not entirely certain of what I'm expecting to find, but drawn nonetheless.

Though this area has been studied more thoroughly than virtually any other archaeological site in North America, it remains an ever-present mystery; which is part of its appeal.

On this day in 1997 I came equipped with my 8" x 8" format falling plate pinhole box camera, loaded with paper negatives, and spent several hours exploring the various ruins at the main site. It was at Pueblo Bonito, the largest of the remaining structures, that I created this image, a window-like opening high up on the wall of the ruins. Though I had a general sense of what I hoped to capture in the composition, I was pleasantly surprised at the results. A contact print of this negative has since graced my living room wall for years.

It's been years since I've been back to Chaco Canyon, the last time being in company with an out-of-state work colleague, where we spent time exploring and shooting video. This image is by no means the definitive representation of Chaco Canyon, but for me it's satisfied my curiosity by providing something tangible to hang my memories upon, while still maintaining that sense of mystery that will always be part of the Chaco experience.

Improvised Camera Building - 8 x 10 Tailboard Box Camera

"Sandia Mountains," Harman Direct Positive Paper in 8" x 10" tailboard camera

Though most of the handmade cameras I've fashioned have been of the pinhole variety, years ago I began experimenting with what could be termed "improvised optics," at first using the objective lens from a 7x50 binocular, which projected an image circle big enough to cover a 5" x 7" film format, though I usually employed it in my 4" x 5" Speed Graphic camera - mainly because of the convenience offered by the camera's curtain shutter.

Eventually, the time came when I wanted to try my hand at building an 8" x 10" camera, mainly because of my preference for working with paper negatives, which can easily be contact printed to good effect, and wanting to work in larger sized images, encouraged by the low cost of large format photo paper as compared to sheet film.

But I was never attracted to the ability of a large format bellows camera to twist itself, pretzel-like, into all kinds of contortions, as is the tradition of architectural and product photography where geometry correction or manipulating the plane of focus might be important. I'm more of a documentary photographer in the tradition of the 19th century forefathers, and thus a simple box camera was more to my liking, but one that could be easily focused.


And thus I came up with the notion of a nested box tailboard camera, so-called because of the rear half of the camera that slides in and out of the front half for focusing, resting upon a baseplate for support. I had been inspired by images of historic cameras seen at the George Eastman House online museum, and figured I could cobble together something functional, if not visually appealing.


So I found a sturdy, flat wooden board as the basis for the camera, and built upon it a foam core front box structure, that houses the shutter slot and aperture plates. The foam core board surfaces are covered with thin countertop laminate that provides a faux wood-like appearance, while the edges are reinforced by wood-printed foam trim molding.


The rear, sliding half of the box is built around a frame made from scrap wood that provides a slot to insert a film holder or view screen frame, which is attached to the rear of the foam core box that slides snuggly in and out of the front half. What provides the light-tight seal between front and rear halves of the box is due to the interior of the camera being flocked with adhesive black craft felt, and that light leaking inward through the gap between box halves has to travel up to the front of the box, then reflect back toward the film plane, in order to fog the film. This is due to the rear half sliding inside the front half; had it been built the other way around, light could easily leak in between box halves and directly hit the edges of the film holder.

Though the camera initially lacked a mechanical shutter, I figured with the slowness of paper negatives and a small enough aperture stop, exposure times could be long enough (>=1 second) as to be accurately timed by hand with a simple guillotine-style shutter.

The length of the camera was initially designed around a meniscus lens salvaged from an industrial semiconductor stepper machine (think of it as a reverse enlarger: a reducer; and made by Nikon), that was mounted to the inside of the front of the box via a bracket and bolts that made it easy to remove and replace with other lenses.


The opening in the front of the box provides for a clear aperture of 2 inches, but meniscus optics are rarely very sharp operated that wide, and so to aid in focusing I made an aperture plate stopped down to 17mm, which clears up the view of these single-element lenses sufficiently to enable a distinctly clear image while still being adequately bright. Unless sunlight is directly striking the view screen, I can often make out a distinct image without the aid of a dark cloth.


I also made a number of other aperture plates, the smallest being 3mm, that cuts the light down sufficiently to permit hand-timed exposures in bright sunlight. Some of these plates are cut from masonite board, while others are fashioned from sturdy black craft paper. In the case of these latter plates, their edges are reinforced with black gaffers tape and when inserted into the camera the excess slop in the aperture slot is filled in with a masonite spacer.


I had fashioned a focal length scale along the lower right edge of the camera, initially calibrated for this first meniscus lens, that enables the camera's working aperture to easily be determined, by dividing focal length by aperture diameter. This method automatically compensates for any "bellows extension factor" caused by close-focusing. Additional lenses are used with an offset number that's added to or subtracted from the scale reading, depending on the lens.

I did experiment with the 7x50 binocular lens, mentioned earlier, that actually makes a very nice 8" x 10" image, with just a bit of vignetting, but its focal length (150mm) is too short, and the box halves too long, to permit that lens to be focused at infinity. However, with the box halves pushed together as close as they will go, that lens operates as a close-up lens for tabletop dioramas and still-life scenes.



Another lens I acquired with the intention of using in this camera was a multi-element lens cell from a Xerox copy machine; however, such optical designs cannot be used with external aperture stops without severe vignetting, which I only discovered after purchase of the lens. Yes, it does operate nicely wide open, but the resulting image is too bright for an exposure to be made with a hand-time guillotine shutter. That lens was later repurposed in my Speed Graphic (since it has its own focal plane shutter), using a special bracket I constructed for the heavy lens, which reminds me somewhat of a Kodak Aero Ektar.


So, I used this camera, on and off, during the last few years with the single element meniscus lens, but wasn't entirely satisfied with the image quality. Then last year I was given a close-up lens, intended to be threaded over the front of a 35mm SLR lens, and found its 275mm focal length and optical quality to be ideal for this camera. This has now been the standard lens I use, of pretty good quality when stopped down, as was done with the top image, taken in far northeast Albuquerque near the Sandia Mountains, exposed onto Harman Direct Positive Paper (which is why the image appears reversed, for those of you familiar with this terrain).




I would be remiss not to describe the view screen itself. Rather than employ a built-in view screen with spring hinges, as is the case with conventional large format cameras, I built a laminated wooden frame that slides into the side of the camera, just like a sheet film holder. The viewing screen is a plastic fresnel magnifier, purchased from a local office supply store, whose smooth side (facing toward the lens) was sanded down with 600 grit emory using a random orbital sander, offering a surface of sufficient quality for composing an image, while the rear fresnel ridges help to focus the image direct rearward, making for a brighter image.

I built the wooden frame such that the distance from the front of the frame to the front of the screen is (nearly) the same as from the front of a sheet film holder to the film plane.

The camera is not nearly as heavy as it looks, due to its construction of layered foam core and countertop laminate, but the biggest challenge in carrying it in the field is its bulk. I've rigged up a makeshift camera strap to help carry its weight, which has helped.


I like that the interior of the camera serves as a storage compartment for spare aperture plates, and that it's rather weather resistant. There are times when I dream of building another version, a bit shorter, enabling me to use that binocular lens, but I have not yet done so. This camera has served as a real workhorse for experimenting with adapted optics as makeshift camera lenses, and is a real hoot to use.


One feature I have not mentioned is that I eventually made my own mechanical shutter, that fits over the front of the box, but that's a subject for another day.

Box Camera Afield at Fiery Furnace

It was almost five years ago when we made this visit to Arches National Park in eastern Utah. It was early April, a time when we typically go on some short, regional vacation in celebration of our anniversary, but that can often present unpredictable weather, especially in the higher regions of the American west.

The drive from Albuquerque brings us through the desolate northwest quadrant of the state along highway 550 to Bloomfield, then through Farmington and over to Shiprock, then up the highway to Cortez, where we pass through the very southwest corner of Colorado, through Dove Creek and on into Utah, making a turn northward at Monticello and up to Moab.



I had been experimenting with a newly built pinhole camera, made from black foamcore board and gaffer's tape, and mounted to a thick slab of wood, providing for a sturdy base, tripod socket and low center of gravity. The principal feature of this camera was once again, like the falling plate cameras of before, an attempt to answer the question of how to make multiple exposures while out in the field, far from home and the convenience of one's darkroom. In the case of this new camera, it employs a side-opening lid gaining access to the camera chamber proper, with a storage compartment behind for exposed and unexposed paper negatives.

Like the falling plate cameras I'd previously built, one has to pause between exposures to change negatives. But whereas before it was a simple matter of tilting the camera forward and releasing the front-most film plate, this camera requires one to find a place to sit down, so as to form a lap upon which to set out one's changing bag, into which the camera is zipped up; then the side door is removed, the exposed paper removed from the film plane and stored in its compartment, after which a fresh sheet is loaded up and the door reinstalled.

There are downsides to this new camera's film changing process. It's slower to recycle between exposures, especially out in the boonies where there might not be a convenient place to sit down. I've been known to crouch down with my back against a boulder, tree or fence post, so as to form that needed table-like lap surface upon which to deploy the changing bag. There's the time required to take off backpack, remove changing bag, sit down, place camera into bag, zip up both closures, insert arms, fiddle with the camera, remove arms, unzip camera, restow changing bag and don backpack once again; then it's off to another spot with tripod over one shoulder and box camera under the other.

The advantages of this new camera, that in many ways outweigh the disadvantages, are several-fold. First, the storage slots in the back of the camera are each wide enough to hold upwards of 100 sheets of paper. That's enough paper for several weeks'-worth of shooting, without ever having to reload film holders in one's car or hotel room; perfect for extended vacations. Second, the camera doesn't have to be lugged around with sheet film holders; four such 8-by-10 holders (permitting only 8 images) are as heavy as the entire camera. Third, unlike the alternatives of a falling plate camera or sheet film holders, virtually unlimited numbers of images can be made out afield in remote areas without running out of film. Fourth, this camera is much less sensitive to be jostled and handled afield, unlike the more delicate falling plate camera designs.

The introductory article to this blog included an image made using this camera atop Delicate Arch. As I recall, I employed the services of my wife to carry the tripod, as we hiked up the long slick-rock mountain slope to the arch. While I carried the backpack on my shoulders and box camera under one arm, this gave us each a free hand in case we slipped or stumbled during out trek upward. I stopped repeatedly to load the camera, make an exposure and reload, all the while fellow hikers would either pass us in silence or pause briefly to inquire if that's a homemade pinhole box camera (I've always been amused by such questions, considering how crude the construction can appear). I found the sloping rock cliffs along the trail a convenient place to sit against to reload the camera, and again did so repeatedly during our time atop the mountain.



The layout of Arches makes it convenient to drive the paved loop road from one hiking site to another. The top photo was created at the Fiery Furnace overlook. I remember it well, because the overlook was crowded with a group of photographers engaged in a workshop, each employing high-end medium-format digital cameras (I'm talking cameras each as expensive as the Subaru we were driving), all of whom were trying, I'm assuming, to find some unique photographic opportunity whilst standing virtually side-by-side, with the same cameras and lenses. Myself, I must admit that I took on an air of smugness, as I shouldered my way up to the railing, deployed Bogen tripod and proceeded to carefully aim the obviously crude camera by means of the viewing dots affixed to the sides and top of the box (and a surprisingly accurate method of framing one's image), me in my grungy work shirt and sweat-crusted boonie hat.

By the time this image was made, I'd been well practiced in the art of pre-flashing paper negatives, a technique that yields a better dynamic range, especially in the shadows, than otherwise. You might want to contrast the tonal rendition of this image with those of the previous several articles, which were made a decade prior and without the pre-flashing technique. I'll cover the details of pre-flashing in another article.

This camera represents a significant evolutionary step in my camera designs, that of large-format boxes simple in design and light in weight (by means of foam core and gaffer's tape construction) yet rigid and stable (due to the heavy wooden base), offering extended operation in remote areas by means of the storage compartment behind the film plane. It's main downside is the need to remove box from tripod between every shot, find a place to sit, and utilize a changing bag. A further evolution, which I've yet to employ, is a camera with its own light-tight, black fabric arm sleeve permanently attached, enabling camera to be reloaded whilst atop its own tripod. One of these days...

Tent Rocks Reprise

The last several articles have had us revisiting a day trip I made to Tent Rocks National Monument in north-central New Mexico, back in 1998, equipped with the 8"x8" falling plate pinhole camera loaded with paper negatives, and a large wooden tripod.

Because of the size and weight of the equipment, my agility was rather restricted, and thus I could only progress so far up the increasingly steep trail before I felt I had to turn back.

The image posted in the previous article shows the entrance to a narrow and winding slot canyon that, while spectacularly scenic, was so restricting that I could barely manage getting through without incurring damage to either box camera or tripod. In addition, because of the narrow passage I could not manage to find adequate footing for the large tripod, else I would have tried an exposure in the shaded gloom between high canyon walls; which would have required several minute's exposure time.

Then there was the matter that this is a public National Monument and there were other people on the trail that day, and attempting such a lengthy exposure, even if I could have managed it, would have meant either blocking their passage or them interfering with the camera gear. So even though I had wanted to try my hand at a pinhole image of the slot canyon, I knew I couldn't. It is personally disappointing when you can sense there is such a powerful subject matter almost within your grasp, but forces outside your control conspire to prevent success.

It was with this sense of temporary disappointment that I proceeded forward, yet remained hopeful that something fortunate might present itself up ahead. After more bends in the trail, as it climbed higher and higher, I suddenly came across this scene and knew immediately that this was what I'd been hoping for.

The trail widens as it makes a bend to the left, in a relatively open area that's a marked change from the confines of the slot canyon now behind us. Though the terrain is steep and sloped, there's plenty of room for fellow hikers to pass, while my tripod's legs can find adequate footing. The challenge will be managing to tilt the camera up toward the conical formations while keeping the tripod from toppling over. I use to advantage the upward sloping terrain on the far side of the trail, where I can adjust the legs' splay to tilt the camera up while the terrain's contour serves to stabilize the center of gravity.

Knowing that this scene was directly exposed to the bright sun, and very light in tone and thus more reflective than other, redder geologies, I opted to shorten the exposure time a bit, so as not to over-expose the landscape.

With exposure complete and film plate properly dropped into the camera's lower storage area, I contemplated continuing ahead, but could already see that the trail only gets narrower and steeper up ahead. I decided that this was a good way to end my day, with several hopeful images yet to develop once back home.

I've returned numerous times to Tent Rocks since then, and every time I do it is with the memory from this day that serves to remind me of the lessens learned, of perseverance and overcoming challenges, of not ceding one's hopes to temporary disappointment but always looking further up the trail for more opportunity.

Tent Rocks Slot Canyon

In the precious article we are back in 1998 and are visiting Tent Rocks National Monument in north-central New Mexico, equipped with the 8" x 8" falling plate pinhole camera and large wooden tripod.

Carrying the camera atop tripod over one's shoulder, the path starts out from the parking area fairly gentle and wide, but as we progress into the canyon it gets steeper and narrower, with frequent stops to consider a potential composition.

The great thing about Tent Rocks is that the further inward and upward one hikes the more spectacular the scenery. But the limitation this day will be the massiveness of the box camera and the length of the tripod, because there is a narrow slot canyon one has to thread in order to get a view of the higher terrain and the spectacular conical formations up ahead that give the site its name. Parts of the canyon are so narrow that one can't progress further without leaning against the canyon's walls and struggling to get the box and tripod through without damage.

And get through I did, but not before first stopping to make this image of the rock striations and the dark fissure-like opening to the slot canyon itself, through whose passage we will find even greater vistas up ahead.

It is sites like this that challenge the whole concept of large format photography, where just being able to gain access to a particular vantage point represents a significant logistical challenge, given the weight and bulk of the gear, especially these box cameras that don't collapse down into a package small enough to fit into one's backpack.

In the next article we will examine my favorite image made with a pinhole camera at Tent Rocks, but couldn't have been made had we not been able to progress through this slot canyon.

The Power of Tenacity

It is 1998 and I have worked out enough of the bugs in the large wooden falling plate pinhole camera, and accompanying wooden tripod, that I've begun going afield, exploring what it might be capable of creating.

Every time I go afield with this bulky contraption I can't help but think of the formative years of photography, in the 19th century, when adventurous explorers, much braver than I, spent weeks or months in the wilderness capturing on photographic plates for the first time the wonders of this new continent. I'm no explorer, for certain, merely walking in the footsteps of giants.

Though the advantage I hold today is that of mechanized transport via automobile, and commercially manufactured films and papers rather than hand-coated on site, it still comes down to having to lug camera, tripod and accessories by hand, absent the portage once provided by pack mule. Today, I'm my own mule.

One drives north from Albuquerque along Interstate 25, then exit at mile marker 264, at the base of La Bajada Hill just south of Santa Fe, heading toward the town of Cochiti Pueblo. Directly adjacent to the massive earthen Cochiti Dam a left turn takes one out along what was then a rough, dirt road to the Kasha-Katuwe Tent Rocks National Monument.

I had learned how to carry the large box camera, mounted atop its tripod, over my shoulder in such a way so as to keep the film plates from becoming dislodged, but I still had to be very careful as I hiked up into the slot canyon at Tent Rocks, in search of photographic possibilities, which I soon discovered to be all around me.

I soon found the main limitation to my handmade tripod was the lack of an articulating head, which limited how far from straight horizontal I could aim the pinhole; this is a canyon, after all. Yet I was able to come away with a number of decent images, among which is this portrayal of a tree which has been partially toppled over by flood waters and whose root system has been exposed by erosion.

Interestingly, I visited Tent Rocks again just this past summer, some 17 years later, and this same tree yet remains in its same precarious position, testimony to the power of tenacity.

Because of the bulk and weight of the camera and tripod, I turned back before entering the steeper parts of the hike through Tent Rocks, but not before recording a few more images, which I will share in subsequent articles.

If there's anything this project has taught me it's reliance upon adequate preparation beforehand, and tenacity to stick with one's intention to fruition, like that tree that yet clings to life in the harsh environment of the New Mexico badlands.

Sandia Mountains, 1994

It was way back in 1994 when I had built this large format pinhole camera and was first experimenting with using paper negatives. I had a few years of darkroom experience under my belt, but there were no Internet discussion forums within which to share one's experience and gain from others' knowledge, and so a person had to do things on their own, study the results and learn from their mistakes.

I remember driving off of Tramway road onto a dirt road, now covered in snow, trying to get as close as I could to the mountain without too much distracting foreground clutter. I ended up with this image, whose principal foreground feature is the tire tracks in the snow. This camera has all along lacked any kind of viewfinding device, even viewing dots, and thus framing up a shot requires a certain amount of luck and serendipity. There is the fact of leveling the tripod head, which helps in getting the horizon straight (unless the terrain is sloped). Perhaps in the future, should I decide to start using it again, I can upgrade it with viewing dots.

What's most striking to me about this whole series of images are the dense shadows, caused by the fact that, in 1994, I had yet to discover the magic of pre-flashing paper negatives, which will be a topic in an upcoming article.


This second image was made during this same outing. Examining the paper negative itself, it appears very much under-exposed. But what detail there is comes to life when reversed into "normal" tones, as I lucked out in getting this image of Sandia Crest, atop which you can just make out the frost-covered antennae. I had to hike a fair bit from the truck, in the snow, and ended up planting the tripod up against this treeline.

The Prototype Falling Plate Pinhole Camera

The year 1994 doesn't seem all that long ago, in a geological sense, but it's still some 21 years ago, a lifetime photographically. That year saw me well into a new and rewarding career, and with it the time to begin working on some of my long-nascent camera-building ideas, that had up until then lingered in various sketch journals. This was my first major camera build, employing the idea of a series of film plates that each could be allowed to fall, face-down into the bottom of the camera, after exposure, revealing behind it the next plate ready to be exposed.


The camera is large and heavy, built from an inner frame of 3/4" square sticks and covered in 1/4" oak plywood, with tripod bushing underneath and carrying handle on top. With an 11" focal length, its pinhole aperture operates at F/458. The shutter is operated guillotine-style, simple and reliable.


The film plates are accessed via a rear door, that's secured by a set of machine screws. Just in front of these screws, on either side of the door, are the control knobs for the film changing mechanism, that slide up and down to drop the front-most film plate when required. Each knob operates a sliding wooden plate located in the space between the outer and inner walls of the box, which in turn have a set of brass pins protruding into the camera, that operate the film plates.


Here the door screw has been removed, with the door ajar.


Both the edges of the door and the door opening are beveled to give a clean exterior appearance, but for light-tight integrity there's a substantial light trap, comprised of a deep groove around the edge of the door opening, with a corresponding protruding flange on the door itself. Also make note of the pusher springs on the inside surface of the door, to help keep the film plates neatly situated up against the control rods.


Here's a view of the interior with one film plate in place. Note the guide rods in the two lower corners, that support the plates and guide their motion as they fall. Unlike the later 5"x8" aluminum falling plate camera, featured earlier, this design lacks the lower lip that keeps the bottom edge from slipping off the rear shelf. A possible upgrade could be made here.

Also note the two sets of notches on either side of the film plate, and the two sets of brass control rods keeping this plate from falling; in actual operation the camera would be tilted slightly forward, then both left & right control knobs would be pushed up simultaneously, permitting the plate to fall forward. In a quiet environment you can hear the plate fall, further confirmation of proper operation. Rather than the plate fall all the way to the bottom of the camera and risk scratching the film or paper, there are two black plastic film capsules bolted to the bottom front corners of the floor that stop the plates' fall. The next film plate would have its notches in the opposite orientation, requiring the two knobs to be pushed down for it to fall; the notches alternate thusly for the remainder of the pack of eight plates.

Though the image format is 8" x 8", in practice this camera uses 8" x 10" sheets of paper or film. There are two 1" wide strips of heavy black paper on the front side of the plates that hold the paper or film in place without the need for tape, permitting the 8" square clear image area.


Here can be seen the front plate in its fallen position, with the two sets of control rods clearly visible on either side of the door opening. Also note the top of the fallen plate is slightly elevated off the floor of the box by the film capsules underneath.

Note how the two curved guide rods, protruding through holes in the bottom corners of the film plates, keep the fallen plates from jostling around the inside of the box, in case the camera is roughly handled. You can easily see how upsetting the fallen plates could otherwise easily cause a plate to block the view of the pinhole aperture, which has happened on numerous occasions and was the main impetus for adding this feature.

Though simple and rugged in design, this camera represents a number of evolutionary steps and upgrades along the way, before its operation out in the field could be guaranteed. Even so, I'm cautious to transport the camera in any position other than upright, and usually carry it by its handle between shots, rather than atop the tripod and over my shoulder. As I indicated earlier, further improvements could be made to make it more reliable. However, it has sat in storage for years, with my attention directed to newer camera projects; 1998 is the last year I see record of it being used. Despite that, this camera is significant to me in that it served as prototype for all the falling plate cameras I subsequently made, while also demonstrating the stick-frame-and-outer-sheathing method of camera construction that I've employed in later designs.

In the next few installments I'll be posting images made using this camera.