Pinhole Photography

Box/container

Needs to be perfectly light tight. Cover all sources of light leak with black tape.
Ideally, the interior of your pinhole camera should be painted mat black to assure nonreflectivity.

Pinhole

Pinholes should be made on a material that is sufficiently thin to prevent diffraction.

Aluminum foil, 0.002-gauge metal (brass shim stock), pie-pan aluminum, soda can aluminum should work well.

1. Poke a hole while rotating the needle/pin (to keep the hole round) and make a small hole into the piece of metal.
2. Attach the pinhole to the box/container with black tape.
   
3. You should also paint the interior of the metal sheet black.
   
4. Cover the hole with black tape until you are ready to expose.

Loading photo paper [in the darkroom]

Photo paper is light sensitive but not to safe-light. So you can work with the safe-light on in the darkroom.

Cut photo paper into small pieces so that it fits in your camera. Only load and unload paper in the darkroom under safe light. (You could also load film instead of photo paper but you need to be in total darkness when you load/unload and develop film.)

Make sure that the emulsion side of your paper faces the pinhole.

Camera Design

There is an optimal pinhole diameter which depends on the focal length of your camera. The focal length is the distance from your pinhole to the paper/film plane. While that being said, you can make fine images without optimal pinhole size. The optimal diameter becomes larger as your focal length increases.

Optimal pinhole diameters (Just for reference. You do not need to follow this)

Focal length (inch)	Optimal Pinhole Diameter (inch)
1	0.008
12	0.02
20	0.03
40	0.04

Exposure

Simply remove the tape that covers the hole when you are ready to expose. Do not hold the camera in your hand while exposing. You will get a blurry picture as you will not be able keep your hands steady enough. (The rule of thumb for photographers is that if the exposure time is longer than 1/60th second, you need to use a tripod.) Place a weight on the camera to hold it steady if it is windy.

Exposure time

Exposure time depends on three things. 1) focal length, 2) hole diameter, 3) available light. You will have to experiment to find what the correct exposure time is for your camera.

• Longer the focal length (larger the camera): longer exposure time
• Larger the pinhole, shorter exposure time. (But if it's too large the image will be blurry)
• More available light (eg. Sun light), shorter exposure time

Sample exposure times when using RC paper

Focal Length	Pinhole Size	f Stop	Full Sun	Hazy Sun	Cloudy	Deep Shade
35mm / 1.4 inch	0.22 mm / 0.0086 inches	f/160	15 sec	40 sec	3 min	8 min
75mm / 3 inches	0.32 mm / 0.0126 inches	f/230	40 sec	3 min	8 min	18 min
150 mm / 6 inches	0.45 mm / 0.018 inches	f/335	3 min	8 min	18 min	40 min
300 mm / 11.8 inches	0.64 mm / 0.025 inches	f/470	8 min	18 min	40 min	90 min

If your developed prints turn out too black, it means your exposure time was too long.

If you do not get any image and the paper is white or the image is too light you need to increase your exposure time.

You will get a negative image with this method. There is a way to turn the negative image into a positive, but that's for another time.

Light leaks

If you suspect light leak (eg. all your exposed paper end up black with no image), place black tape over the pinhole to cover the hole. Place the camera in the light for a few minutes with unexposed paper inside. Then develop the paper. If your paper turns gray, you have a light leak in your camera.

• The images you will get will be a negative (light areas dark in print). There is a way to convert it into a positive by making another print (contact printing) but we'll stick to negative images for the workshop.
  
  
• The camera itself could be a sculptural art object. What can you think of that may be thought-provoking if it were a camera?
  
  
• Pinhole cameras require long exposure times (compared to regular cameras which have shutter speeds that are less than 1 second). What kind of subject matter makes sense with long exposure?
  
  
• Pinhole cameras can be small, unassuming, and cheap. You may be able to place them in 'interesting' or 'unusual' places where you normally would not place a more expensive camera. Or conversely, it may call attention to itself because of its atypical form. What kind of photographs would that yield? How does it change the relationship between the subject and the camera/photographer?
  
  
• Pinhole cameras have infinite depth of field. That is, all areas from near to far are equally in focus. (This does not happen with lens based cameras.) Try putting an object adjacent to, and far away from the camera.
  
  
• Investigate the relationship between the pinhole and the paper plane. Take a picture of a building or a box and see how the parallel edges of the building or the box recede into space. What kind of perspective is this? Experiment with the distortions created. What happens if the camera is cylindrical? What happens if the camera is a box? What happens if you load paper with folds?