Adventures with multi-pinhole cameras

Malin Fabbri builds and tests multi-pinhole cameras. An excerpt from Diffusion magazine, volume II.

Writer and photography / Malin Fabbri

I have always been drawn to alternative photographic processes for many reasons. Among those reasons exists the potential for what I call “happy accidents”: events and outcomes that occur without intention and that ultimately result in a better print.

Typical happy accidents are often related to the print-making process: an unintentional spill of emulsion on paper, a brushstroke taking on a shape of its own or a color shining with an unexpected hue. Such accidents, commonplace in the pinhole photography, can lead to a very pleasing print (and, in my case, a very happy photographer).

These “accidents” may also occur in-camera, however: intriguing light leaks, a failure to fully wind between exposures, or an imperfect container all can result in surprisingly beautiful images. When it comes to building a pinhole camera, though, why leave these events to chance? If one can create his or her own luck, shouldn’t it also be possible to lure the happy accident into forming?

Unique Characteristics of Pinhole Photographs

Many special effects can be created by modifying a pinhole camera. As an example, the camera can be designed with a bent film plane, which distorts horizons and subject matter. Additional effects can be obtained by modifying the focal length: a camera with an extremely short focal length creates a wide-angle effect, whereas a telephoto effect may be created by building a camera with a long focal length. Another alteration involves zone plates, which are a series of clear and opaque rings that add soft-focus and sometimes a halo to the subject. Furthermore, a “cubistic” effect (multiple exposures) can be achieved by building a “chest of drawers” style camera. This effect involves several pinholes exposing light on the paper or film.

When it comes to uniqueness and special effects, my favorite pinhole camera technique involves using multiple pinholes. The first multiple pinhole I ever set eyes on was taken by Jan Kapoor with her 360-degree camera. With such a camera, subjects and landscapes merged in Jan’s images, touching and interacting with each other. Jan’s pinhole camera was created using a hexagonal box. It has six separate pinholes of the same diameter on each side of the box. Inside the camera, the film is wrapped around a cylinder, making it possible for Jan to expose the film from several angles. She is able to use those six pinholes individually, simultaneously, instantly or over a period of time to create her wonderful landscapes.

Constructing Multiple Pinhole Cameras, or multi-pinhole camera

Now that we’ve covered some basics, let’s delve a bit deeper into my favorite pinhole camera technique. In the experiment I will describe, I had a particular goal in mind: I wanted to see what kind of results I could get by creating and comparing two multiple pinhole cameras of similar size but of different shape: one square, the other round.

The first step? Choosing my containers. I admit that I am one of those computer nerds who buys software and then keeps the boxes, full of manuals and CDs, on the bookshelf. When I was looking for a container for my most recent camera a big, sturdy, completely black (and therefore already prepped as a pinhole camera) “Apple” box caught my eye. I was forced to sacrifice a few manuals into the recycling bin, but I decided this box would be perfect for making a square multi-pinhole camera. The second container was even easier to choose, as it involved washing down a tin of very tasty “Anna’s Gingerbread Biscuits” with a few cups of tea to free up a perfectly round container.

I then spent a day with Lena Källberg, in her studio in Stockholm, to build and test my two cameras (ingeniously named “iPinhole” and “Ginger”). Lena, who is also an avid pinholer, built her own multi-pinhole camera using a round cake tin. She named it “Turizt” after the name on the box. You can call me crazy, but I have a theory that computers and cameras work best when they have a good name. If you don’t already have names for your cameras, give it a try…you might be surprised by the results.

After contemplating the technical details, I decided to give the iPinhole camera three openings (the openings would eventually hold a piece of aluminum, through which the pinholes would be drilled): a square opening in the front – piercing the Apple logo – and one in each side. Ginger received three openings as well, each spaced evenly across the front of the tin. Lena decided to make hers a 360-degree camera, which meant the Turizt camera was the beneficiary of three openings, carefully measured and spaced exactly equidistant around the box – she is a perfectionist!

Each of our cameras received an inner circular can for fastening the paper. For the iPinhole and Ginger, the inner can was placed in the center. The inside of Ginger was then sprayed with matte black paint. Turizt was given a coat of matte cardboard paper while iPinhole, already black both inside and out, needed no extra coloring.

After prepping the cans and the box, it was time to work out optimum pinhole sizes. We elected to use “PinholeDesigner”, which is a great calculator that can be downloaded and installed from this site: www.pinhole.cz/en/pinholedesigner. Our calculations revealed that the optimum pinhole size for both iPinhole and Ginger was between 0.31 mm and 0.40 mm. Turizt had an optimum pinhole size of 0.36 for all six holes. Making nice, round pinholes of the right size is one of the trickiest challenges in constructing a pinhole camera. We selected to use an old beer can, which was cut, sandpapered smooth, pierced with a needle, scanned in and measured in Photoshop, pierced, sandpapered again, scanned and measured again, and again, and again.

One might ask at this point: why drive ourselves crazy trying to make the perfect hole? For this reason: a perfectly calibrated pinhole camera has an infinite depth of field, which means that everything in the final photograph will be in focus. That quality is what we were after, and we managed to make all the holes with a difference of less than 0.02 mm.

After we had determined the size of the pinholes and the focal length, we could easily work out the f-stop of our cameras using this formula: focal length/diameter of pinhole=f-stop

Testing the New multi-pinhole Cameras

All three cameras were quite close in their f-stops. The iPinhole camera had f-stops ranging from f/179 to f/211. Ginger’s range landed between f/160 and f/184, and Turizt had an f-stop of f/180.

When the paint had dried and we were finally happy with the pinholes, it was time to test for light leaks. We journeyed into the darkroom and inserted a brand new sheet of unexposed paper into each camera and placed the cameras in the sun for a few minutes, WITHOUT opening the shutters. The paper was then developed and each sheet emerged white as snow – perfect, no light leaks!

We could finally head out to the park to field test our cameras. It was late in the afternoon, but it had been a lovely day and it was still sunny. The September sun was setting behind a number of buildings. After consulting the exposure chart listed in From pinhole to print (also shown here) I decided on an exposure of “cloudy at f/180”. This translated to an exposure time of two to four minutes, so I selected to expose the paper for an average of three minutes.

Ginger behaved excellently during the exposure, and the black tape shutters worked fine. Turizt also performed well. iPinhole, however, was a different matter. The use of a black tape shutter on a cardboard box was not optimal, as part of the box’s paper tore loose when I pulled the tape away for exposure. This not only ripped pieces off the box but also rendered the black tape useless for further exposures. As I had not taken this into consideration, I had no more black tape with me in the field and had to cover the holes with my hand on the way back to the darkroom. Not ideal.

It was now late, however, and the sun had set. It was time to call it a day – no more time for test shooting. We returned to the darkroom to develop our prints. iPinhole’s test print did develop a black patch on the side of the paper – I suspect due to an inability to close the shutter properly. That very night, I used a beer can to create a reinforced plate over the holes in iPinhole, so I would be able to remove the black tape without parts of the box falling off. Much better!

The cameras were now complete, and the test prints developed. Complete, at least, in the cases of iPinhole and Ginger. Lena achieved a very nice test shot with her Turizt but, because she is a perfectionist, has decided to fine-tune her camera. She is working out the optimum space between the inner can and the outer can to make a perfectly seamless gap between each image. So far, her conclusion is that five pinholes, coupled with the use of a smaller outer can, will result in a perfect multi-pinhole camera.

Although we have improved our chances of avoiding accidents, we are still treated with the unpredictability of pinhole photography and those aforementioned happy accidents. To the seasoned photographer, pinhole cameras may seem too simple to offer much versatility in the area of image-making. However, these “limitations” often help a photographer free him or herself from the discrete and often rigid technical settings that more modern cameras possess. Such pinhole cameras, utilizing one or more tiny, drilled holes, record the world differently than the way our eyes see it and add unexpected characteristics to reality. In this way, what were once limitations may then become the opposite: they may become, in fact, opportunities, inspiring creative problem-solving in less than perfect situations.

An explanation of how the multi-pinhole camera reverses the image

When light enters a pinhole camera, the image is reversed and upside down. A multi pinhole camera will not make panoramic images, as perhaps would be expected since each image is reversed. An object that sits at a dividing line between two pinhole projections will be split into two pieces that are on the far sides of the negative. To achieve panoramic images you would in fact need a very complex design using mirrors. What you achieve instead with a multipinhole camera is an interesting blend of the landscape and and unexpected merging of objects. The images reverse into each other, one after another.

This article was published in Diffusion magazine. Malin Fabbri moved from Sweden to London to study, and earned an MA in Design at Central St. Martin’s. She has worked professionally with big media names in London, and has written two books on alternative photographic processes. In 1999 she began AlternativePhotography.com, and continues to be it’s editor.