Tricks to Tame a Pinhole Camera

A pinhole camera usually consists of just a box and a tiny hole which you pierced with a needle yourself.
Film is put inside the box, the hole uncovered momentarily to let the film exposed by the light, and that’s it.
You just took a picture.

I have a “modern” version of it, which friend Tony bought me at Toys ‘r us.

I just had to assemble it and pierced a hole (=the lens). In the pic above it’s the black dot inside the white circle/elipse.

It has a film loader, a winding knob and a shutter (to cover and uncover the hole). What a nice toy!

With a pinhole camera you can see the very essence of a camera. How about the results? It’s blurry, often (and sometimes totally) over- and underexposed because you have to guess how long to open the hole and let the film exposed.
And normally the pictures are shaky too, because the hole is so tiny you have to open the hole about 1 second outdoors on a bright sunny day (indoors you need minutes or even half an hour to get a picture!).

I have some tricks to solve the problems though…
Now some of you pinhole camera lovers might say this would take a way the fun of not knowing what results you will get. In that case….do not read further

Problem 1: Shaky photos caused by typical long exposures (0.5 sec and more) required by a pinhole camera.
Trick 1: Use a tripod

Glue a nut (not the one you can eat) on the bottom of the box so you can attach the camera to your tripod.

Problem 2: Over- or underexposed photos because we don’t know the size of the hole (=aperture), hence we can’t determine the correct exposure times.
Trick 2: Find out the aperture of your camera. The following explanation requires knowledge about exposure time and aperture.

Take a series of pictures with varied exposure times in a room with constant light (= no sunlight). First just guess the aperture. Take my guess: 180 (my pinhole camera has aperture 360, so 2 stops smaller than 180).

Take an exposure reading with your normal camera, or better with a lightmeter.
Yes, your camera (actually the lens) usually lets you go until aperture 22. A lightmeter lets you go until about 90.

If you use aperture 22 for the reading, calculate the exposure time for aperture 180 with help of this list of apertures (1 stop decrements):
22-32-45-64-90-128-180-256-360.
Example: You get exposure time 1 sec at aperture 22. To aperture 180 you go down 6 stops. So you have to go up 6 stops with the exposure time: 2-4-8-15-30-60 secs.
So it’s 1 minute exposure time for the guessed aperture 180. Now take exposure from -3 stops until +3 stops in 1 stop increments.

Develop the results and judge the negatives. Pick the picture with the correct density, that’s the one that’s not too thin (=underexposed) and not to black (=overexposed).
If for example the one with the correct density is the one you exposed +2 stops, then your cameras aperture is not 180 like our guess, but 360 (see the list again).

Problem 3: We know the aperture but the pinhole camera doesn’t have a built in lightmeter to determine the correct exposure time.
Trick 3: Now this is silly. Of course we take a lightmeter or a camera with built in lightmeter to help us determine the correct exposure.
Attach the list of apertures above on your pinhole camera body.

Problem 4: Now we can determine the correct exposure time. Since we have to open and close the hole manually,
how do we know how long we have to hold it open for, say, 8 seconds?
Trick 4: Take a normal camera. Set at 8 sec for this example. As you open the pinhole camera press the shutter button of the normal camera.
When you hear the shutter of the normal camera closes, close the pinhole camera also. Of course there are time differences, but for long exposures (2 secs or longer), they are negligable.

That’s it, have fun!