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Once the pin hole camera has been assembled and the imaging principles and its efficiency of this camera established and tested the experimenter is equipped for taking pictures of his/her desire. However, it is best when a photo laboratory is being set up prior to taking any pictures. There are required four photographic dishes (13x18cm) of which each contains approx. 1/4 liter of developer, water, fixer, and water, respectively.
1. Charging of the camera in a safe-light environment
a) with photographic paper: The box containing the photographic paper (9x13) should only be opened either in complete darkness or when using a safe-light, a single paper should be placed, with the photo sensitive layer facing up-wards, inside the film compartment. The photo sensitive layer is slightly reflective and feels slightly sticky due to the through excitement moist hands (gelatine). Corners or double-sided adhesive tape (Photo sticker) prevent the photo sensitive material from slipping or falling over.
b) with orthochromatic film: As with photographic paper the grey (photosensitive) layer needs to face up-wards towards the pin hole. In case the photosensitive side faces the bottom of the film compartment light will have to enter through the halation protective layer and the film requires a much longer exposure.
Afterwards, the photographic screen box has to be removed from the camera casing, the film compartment will be attached, and the pin hole needs to be closed. When the photographic paper or film material has been stored away in its light-proof packaging the camera is ready for taking its first picture.
You may either use your thumb or the aperture slide for closing the pin hole. By positioning the aperture slide right at the centre of the pin hole the closure of the pin hole is guaranteed.
2. Taking a picture
The pin hole camera has to be either fixed to a tripod or placed on a vibration-free base and aligned with the desired subject. The pin hole needs then to be opend depending on the lighting conditions. Do not move or shake the camera! (The exposure time of photographic paper and film at sun shine of about 20 and 3 seconds respectively can generally lead to quite respectable results. The calculation of aperture and exposure time are illustrated in the Exposure Time Calculator, which belongs to the pin hole kit.)
The pin hole has to be closed right after the picture has been taken and the closed camera needs to be taken to the photo lab with the prepared photo dishes waiting.
3. Developing the photo material
Only under safe-light conditions should the film compartment be opened, the photo sensitive material has to be submerged immediately in the developer. It is best to keep the photo sensitive layer facing up-wards to observe the developing process. Some slight rocking of the photo dish with the developer can enhance the uniformity of the developing process over the entire picture. Just like magic-an image will emarge after only few seconds. The whole picture is completely developed after 90 seconds: It is a negative the wrong way round!
The judgement of a 9x12-negative film becomes even more difficult in safe-light than the one of photo sensitive paper. The emulsion layer of the film can be easily damaged when it is wet, which is why films should be handeled and taken from photo dish to photo dish with rubber gloves and the use of metal picture tweezers must be avoided. Be careful, do not carry any chemicals from one to the other photo dish.
(In case a picture is even too dark in the image of a shade the exposure time should be halfed (e.g. 10 seconds) in the next trial. When the picture is to bright the exposure time can be doubled (e.g. 40 seconds).)
4. Fixing
Lift the developed pictures with a pair of photographic tweezers out of the developer and let the remaining developer drip back into its photographic dish.
Carfully rinse the pictures in the photographic dish filled with fresh tap water (removing the remaining developer chemicals) before carefully sliding them into the fixer bath.
The fixer process should be finished after 5-10 minutes when gently rocking the photographic fixer dish.
(Note: Do not dip the photographic tweezer into the fixer since otherwise fixer chemicals may be carried over to the developer dish and eventually neutralise the developer bath. In case there are several pieces of photographic material in the fixer dish ensure that they are detached from each other as they would remain unfixed.)
5. Rinsing with water
The processed photographic paper or film will require rinsing several times with water to remove remaining chemicals on the material.
6. Drying
Laminated photographic paper drys in air creasefree. To accelerate the process a hair dryer or a hot-air dryer may be utilised dry press as they are required for drying baryt paper become too hot for synthetic-coated photographic paper (PE-paper) and my get stuck to the dry press.
The film negatives should be treated with a wetting agent to prevent watermarks.
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