An extract from Laura Blacklow’s book New Dimensions in Photo Processes written by Jesseca Ferguson and Walter Crump.
In an age when experience is becoming more virtual, the handmade aspects of photography become more important to the maker and the viewer alike. Contemporary images may be hybrids that combine digital methods with hand coloring, collage, and a nineteenth-century technique or two.
In this climate of experimental imaging, pinhole photography offers unique possibilities.
Whether you think of your pinhole camera as a sculpture that takes pictures, a recycled object, or a large-format camera, it will be uniquely yours. You can customize, decorate, or embellish your pinhole camera any way you like. The design of your camera, when exhibited alongside the images it takes, can make a visual or political statement not possible with any other imaging method. There are many reasons to experiment with pinhole photography: the incredible distortions you can get in your images, economy, infinite depth of field (all objects depicted are equally in soft focus), multipinholes (allowing multiple views simultaneously, large or unusual formats, etc.). Almost any object can become a camera!
Please read the Safety section in the book to become familiar with proper handling of darkroom chemistry.
Osberve sound safety practices when operating power tools, or working with scissors or mat knives.
- Orthochromatic film or black-and-white photographic paper. Any film will work in a pinhole camera, but ortho film, as described in this chapter, can be handled under a safelight and is thus a good film to start with.
- Potential camera. Choose a can, box, or other (potentially) light tight container that will easily accommodate insertion and removal of film or paper. Good examples include paint cans, oatmeal boxes, lunch boxes, purses, suitcases, guitar cases, 35 mm film canisters, garbage cans with lids, etc. Metal tins with tight-fitting lids, such as the ones used to package cookies or loose tea, have a high success rate as first-time pinhole cameras. A conventional camera (any format) can be modified to become a pinhole camera. Simply remove the lens and replace it with a pinhole mounted in light-tight material, such as a lens cap.
- Mat knife, scissors. These are useful for cutting metal stock for pinholes or for building a camera from scratch out of mat board or cardboard. In addition, you can cut strips of mat board or foam core to act as channels, keeping the film or photo paper in place inside the pinhole camera.
- Black spray paint. Matte finish black spray paint can be used to darken the interior of your camera (especially recommended for white or reflective camera interiors). Lightly sand the inside of a metal box for better spray paint adhesion. Two light, even coats of spray paint will give you the best results. (Let the first coat dry before applying the second.)
- Lightweight sheet metal. Brass shim stock (available from hardware stores and hobby shops), the flat part of an aluminum pie plate, or the side of a soda can all provide metal suitable for making a pinhole. (Aluminum foil will also work, but it tears easily.)
- Sewing needles or pushpin. These are used to “drill” the pinhole.
- Emery sandpaper. Sandpaper designed for metal is used to smooth away the burr created when drilling the pinhole.
- Drill, files. These tools are used for cutting and smoothing holes in metal tins, wooden boxes, or other items being transformed into pinhole cameras.
- Magnifying glass or photo loupe. These items are used to check your pinhole for roundness and lack of debris.
- Canned air. A puff of air will clean pinholes of any debris left from sanding.
- Black photo tape. 1⁄2–1 in. (14–28 cm) wide. Black photo tape blocks light well and, therefore, is good for making a simple shutter or for mending light leaks.
- Permanent black marker, black acrylic paint. Either item is good for touchups to reduce reflections inside a shiny metal pinhole camera interior. Thick black acrylic paint can patch small light leaks.
- Weight or tripod (for cameras made with tripod mounts). These items can be used to steady your pinhole camera when working outside on a windy day. A brick can simply be placed on top of a camera, or a small metal weight can be attached to the top or bottom of a camera. (A good fastening method is removable, reusable adhesive putty available from art supply stores.)
- Watch, notebook, and pen. These items help record your exposure times and results. Keeping good records will make your subsequent exposure times more accurate.
- An ordinary object, such as an oatmeal tin, is turned into a pinhole camera. The interior of the would-be camera is blackened (to cut down on interior reflections).
- An opening is cut into one side or one end of the potential camera.
- A pinhole, drilled into a 1×1 in. (2.5×2.5 cm) or larger square of lightweight metal, is taped in place behind this larger opening using black photo tape.
- A flap of black photo tape is created to act as a simple shutter.
Making a Pinhole Camera
1Creating the Camera
Once the camera-to-be is chosen, spray paint the interior matte black (unless the interior is already a dark, nonreflective color). Double check for potential light leaks (such as around the hinges and handle of a child’s lunchbox) and repair them with black photo tape. Next, using a mat knife or a drill bit 1⁄2in. (1.25 cm) or larger, cut a small window in the side or end of your camera, preferably centered (for better image coverage). As this opening will accommodate your pinhole, be sure to make it smaller than the approximately 1×1 in. (2.5×2.5 cm) square of metal containing your pinhole. File and sand down the rough edges around this window carefully, so that your pinhole metal can be taped in place snugly behind it (using black photo tape).
2Making the pinhole
To make the pinhole itself, cut an approximately 1×1 inch (2.5×2.5 cm) square of metal, and place it on a piece of cardboard or foam core. Using a sewing needle with the blunt end covered in tape or embedded in the eraser of a wooden pencil (in order to cushion your finger) or pushpin, press down into the center of the metal square until the needle pierces the metal, leaving a burr on the opposite side.
3Refining the pinhole
Sand the burr down, using emery sanding paper, on both sides of the metal. Reinsert the needle into the hole as needed to drill and burnish the inside of the pinhole by gently spinning the metal around the shaft of the needle. Your goal is a perfectly round hole, free of metal debris, in a smooth metal plane. Holding the metal up to a light source, use a film loupe or magnifier to verify that your pinhole is round and free of debris.
4Inserting the Pinhole
Center the pinhole behind the larger opening in your camera, and tape it into place with black photo tape. Attach your black tape shutter flap and you are ready to go into the darkroom and load your camera.
5Loading the film or paper
In the darkroom, insert your light-sensitive material at the back of the camera, with the emulsion (light sensitive side) facing the pinhole. Hold the film or paper in position using reusable adhesive putty or tape (at the corners or in “rolls” at the back of your film or paper). This method also allows you to cut your film or paper into odd shapes. Remember to place your shutter made of black photo tape over the pinhole before leaving the darkroom.
6Making an exposure
Work outside (faster than inside) for your first exposures, using a mixed light and shade situation and facing away from the sky or direct sun. Work closer to your subject than you normally would with a lens camera, and time your exposure in seconds or tens of seconds, even minutes, depending upon the light situation. To expose, remove the tape shutter and replace it at the end of the exposure.
7Developing the negative
In the darkroom, unload the “negative” from your pinhole camera and develop your ortho film or photo paper. Develop by eye, in paper developer (1–2 minutes), followed by stop bath (30 seconds), and fixer with hardener (5 minutes) for film, without hardener for paper. Water rinse as the manufacturer directs (shortened for film by using fixer remover).
Experiment, get to know your camera, have fun—and welcome to the world of pinhole photography!
– Using black photo tape (with one end folded back for easy accessibility), make a simple shutter to place over the pinhole when not exposing your film or photo paper.
– For exposure times, work by trial and error, keeping the following four factors in mind:
- Light conditions (inside/outside, time of year, time of day, geographical location).
- Speed of light-sensitive material (film or paper) being exposed in your pinhole camera.
- Size of your pinhole (smaller pinhole is slower, larger pinhole is faster).
- “Focal length,” or the distance from your pinhole to your film/paper. A shorter distance means faster exposure, with a more wide angle view. A longer distance means longer exposure, with a more “normal” or telescopic view. If you work consistently with one camera and keep notes on each exposure, you will learn a lot about light, about pinhole photography in general, and about that pinhole camera in particular. For those desiring more exact methods, see the exposure charts provided by Eric Renner in Pinhole Photography: Rediscovering a Historic Technique and other resources.
– Angle of view (normal, wide angle, telephoto). To get a “normal” looking image, measure your film/paper diagonally, then build a camera with a pinhole that is that same distance away from the film or paper. Thus, to produce a “normal” 4×5 in. pinhole image, build a camera that is 6 in. deep (the diagonal measurement of the 4×5 in. film). This 1:1 ratio is based on human sight: the diagonal measure of the receptors in the back of the human eye is equal to the eye’s diameter. (“Normal” presumes that your film plane is flat, not curved, as in an oatmeal-box camera.)
– Image coverage/focal length ratio. As the cone of light entering your camera from the pinhole is interrupted by the plane of film, you will get different areas of coverage, depending upon the distance between pinhole and film plane (focal length). Pinhole expert and author Eric Renner discusses what he calls “the image-diameter-to-focal-length ratio” in his book Pinhole Photography (see Annotated Bibliography). Image diameter is approximately 31⁄2 times the size of your camera’s focal length. Thus, a 2 in. deep camera would give you approximately 7 in. coverage (7 in. diameter circular image). Keep this ratio in mind when making multipinhole cameras.
– Image coverage and avoiding unwanted vignetting. The camera-to-be should not have thick walls, lest you create a “tunnel” effect that prohibits the light admitted by the pinhole from exposing much of the film or photo paper in the camera, thus resulting in a vignetted image. If your chosen camera object has thick walls, simply make the original hole larger in order to permit a broader beam of light to enter the camera interior.
– Reducing potential glare. The back of the pinhole metal may be blackened with marker to reduce glare, but be careful not to accidentally “fill in” your pinhole with ink.
– Pinhole size. Any size hole will work, with a smaller hole yielding a sharper image. For details on aperture size and focal length, see Chapter 5 of Eric Renner’s Pinhole Photography or Jim Shull’s The Hole Thing.
– Built-in holder for film or paper. If you will be using a consistent size or shape of film or paper, you can make a simple in-camera film holder using channels cut from foam core or mat board, glued into place opposite the pinhole.
– Avoiding unintended blurring of image. Keep your camera steady on a firm surface throughout the entire exposure. (Move camera or subject for deliberate blurs.)
– Troubleshooting negatives. If your negatives are completely dark, or are dark in certain blotched or streaked areas only, your camera may have one or more light leaks. Check your (empty) camera for light leaks by peering inside as you hold it up against a light source. Make any necessary repairs with black photo tape or black acrylic paint. If you can see some image, but the overall negative is too dark, you may be overexposing your film or paper. Reduce the light entering your camera by shortening exposure time or by exposing in a less light-filled setting. (Rarely will you need to correct overexposure by making a smaller pinhole.) If your negatives have little or no image at all, you may simply be underexposing them, given the light situation, pinhole size, camera depth (focal length), and speed of film or paper you are using. Possibly you may have forgotten to open the shutter, or have loaded the film or paper backward (emulsion side away from the pinhole).
New Dimensions In Photo Processes
by Laura Blacklow
A step-by-step manual to many of the processes.