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How-To: Digital Pinhole Photography
Nearly 40 years ago, scientist and author Forrest M. Mims III wrote an article titled “The Pinhole: A ‘Lens’ that Just Won’t Quit” that was published in the April 1974 issue of Popular Photography. His enthusiasm for pinhole photography, taking photographs with a 35mm film camera equipped with a pinhole instead of a lens, hasn’t waned over the years.
In MAKE Volume 33, Forrest shares his simple tutorial for taking pinhole shots with a digital camera, as part of his ongoing Country Scientist column. He first gives us background on characteristics of pinhole photographs and exposure times, then teaches how to make a super basic foil pinhole as well as a better aluminum pinhole from a soda can. Check out the full how-to.
From the article, here are some pinhole images Forrest has taken, along with explanations:
Figure A shows the sharpening that resulted from reducing the pinhole size from 0.6mm to 0.3mm. Three images of the sun and an arrow on a computer screen, photographed through 3 pinholes mounted on a Canon 40D digital camera. The largest pinhole (the width of a 0.6mm-wide pin) produced the brightest but fuzziest images (at right). The smallest pinhole (0.3mm) produced the dimmest but sharpest images.Another characteristic of pinhole cameras is nearly infinite depth of field. Make a pinhole photo of a very close object with a distant building or mountain in the background — it’s all in focus. You can even use the sun for the distant object (Figure B), but it will be fuzzy unless the exposure is brief. Handheld beverage-can pinhole image of barbed wire illuminated by flash and the morning sun (1/60 sec., ISO 320).
Pinholes punched through foil or thin metal leave behind a projection of torn metal on the exit side known as a crown burr. Pinhole photographers often remove the burr with sandpaper. When left in place, the burr can cause uniquely beautiful effects, especially when making pinhole photos of the sun, as shown in Figure C.
Pinholes admit much less light than a conventional camera lens, so exposures must be longer. This usually means the camera must be mounted on a tripod or placed on a stable surface. But thanks to the high sensitivity of digital cameras, handheld photos are often possible when the scene is brightly illuminated. I’ve made handheld pinhole photos at speeds from 1/30 second (bright sunlight) to 1/8,000 second (the sun itself). Figure D shows three dramatically different views of a high-voltage power transmission tower, all made without a tripod.
