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Re: PinHole Camera

Area: Other
Posted By: Prudence Risley, Collective Enigma Elucidator
Date: Sat Jun 1 23:06:22 1996


> Ok, How do i get a PinHole camera to take
> a picture without putting a Polaroid camera inside of it?

Pinhole camera's are actually fairly easy to make.

Before you make the camera, first decide on how you would like to take pictures. Black and white is easier (and more fun) to work with. You have choices of using black-and white negative film, or black and white paper. Normal black and white photographic paper will produce a 'negative' image of whatever you photograph (i.e. a sunny day will appear dark) while 'positive paper' will produce a positive image more like what you see. Film and both types of paper can be purchased at most any photographic supply store. For starters I'd recommend using paper. Both Ilford and Kodak brands of black and white paper should be fine. Try starting with plastic- backed 'rapid contrast' paper.

There are many ways to go about building a camera. I'll describe how I generally go about it; you can also follow the instructions from this page in France which describes a similar method.

Important things to consider when making the camera are:
1. The distance from the front of your camera to the back -- where the paper will be placed. This distance determines the depth of field that your camera will have -- a longer distance will have a greater depth of field or range in which objects will be in focus. A shorter distance will have less -- rather like being nearsighted. A camera with dimensions of 10cm long x 5cm high x 5cm wide is fine to start with.

2. How big a piece of paper you want to use. The above camera will hold a piece 5cm x 5cm, anything larger and you'll have to build a bigger camera.

3. Making your camera light-tight. If light leaks in from places other than the pinhole, you won't get a clear image.

Materials

Here's what you'll need -- you should have an adult help you, particularly with the photographic chemicals.

-- For the camera: a small cardboard box, scissors, some aluminum foil and electrical tape, preferably black.
-- A dark room in which to load your camera with paper and develop exposed images. Bathrooms are particularly good as you have a source of running water nearby. Close yourself in the room and turn off the lights. If you can't see your hand clearly before your eyes once they adjust to the darkness, the room should be fine.
-- A safelight is nice to have but not required. This type of light, usually amber in color, will let you see what you're doing while developing/loading the camera, without exposing the paper.
-- Photographic paper cut to fit in the back of the camera -- be certain to cut the paper in the dark or in your dark room + safelight.
-- Photographic chemicals for developing exposed paper. All of these chemicals can be purchased at a photographic supply store, and shouldn't cost more than $10.

-- Three trays or containers to hold the above solutions. The containers should be large anough so you can float your pieces of paper in them.
-- Running water (i.e., the bathroom).
-- A pair of tongs to move developing paper from one solution to the next.
-- A 'changing bag' if you have one available -- this bag will let you take out/put in fresh pieces of paper 'in the field.'

Making the camera

  1. Decide which end of your box will hold the paper and which end will have the pinhole lens in it.
  2. For the end that will have the paper, make certain you can open and close this end to put paper in/take it out again.
  3. Seal any seams in the remaining four sides with the black electrical tape. If your box is made of thin cardboard, you may want to cover all of it with aluminum foil, then tape things together.
  4. Cut out a small sqaure 1cm x 1cm in the exact middle of the front panel.
  5. Cover this hole with black electrical tape, or aluminum foil + tape.
  6. Take a pin, stickpins or hatpins seem to work best, but a medium-sized safety pin will work too, and make a single hole in the tape/ aluminum foil. It is very important that you make this hole no bigger than 1mm in diameter. If the hole is too big your images will not be in focus.
  7. Take a piece of electrical tape ~ 3cm long. Fold 1cm back on itself to make a tab, and place this over the hole. This piece of tape acts as the 'shutter' to the camera.

Now that you have a camera, take a piece of photographic paper cut to size and place it in the back of your camera. You can sitck a piece of tape on back of the paper to hold it in place. Close the box and seal the remaining seams with aluminum foil or electrical tape. Note -- the advantage of using a metal tea can is the lid can be easily removed, and makes the interior light tight without having to tape things together.

You're ready to take a picture!

Experimentation is the best way to learn what light settings and exposure times work best for your camera. Keep a notebook handy to record what you photograph and how long you expose the picture -- then you can decide the best conditions.

To expose the paper, put the camer on a steady surface and gently raise the tape shutter, sticking it to itself or placing it elsewhere on the camera. Start with an exposure time of 35-45 seconds. When finished, replace the tape shutter. You're now ready to develop your first picture. If you have a changing bag at hand you can remove the exposed paper and put in a new piece.

Once you're in your darkened bathroom, remove the paper. Place it in the developer solution. If you have a safelight you should see dark areas appear within 15-20 seconds. If you don't have a safelight, set a watch for one minute. After a minute use the tongs to move the paper into the stop solution. Swirl the paper in the stop for approximately 30 seconds. Move it immediately into the fixative.

Once the paper has been in the fix for 30 seconds, it's ok to turn on the lights. The paper should sit in the fix for 2-3 minutes, then move it to a tray under running water for another 2-3 minutes to wash off the fixative solution. Have a look, admire, and decide what you'd like to photograph next!

Pinhole photographs will not produce the crisp and clear images that you normally get with regular cameras -- the effect is often fuzzier and more 'sureal.' The same processes can be used to expose 35mm roll film or black and white photographic plates.

Bon appetit..

P.R.

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