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PRINTING
Printing is the process of focusing the image on the processed negative onto a photographic paper .it means making a positive image that is the same size as the negative on a photographic paper, the positive image formed have to be again enlarged to a reasonable size.
Contact Printing
This is a technique whereby the negative is placed on a sheet of contact print and exposing it with a low voltage disk lamp, which gives an even lighting. An enlarger is not required at this stage. After these period of exposure on the contact sheet, the contact sheet have to be processed again through a series of three solutions a just like in the film processing i.e. in developer, stop bath and fixer solutions,
Contact printing requires a normal contrast grade paper with a white smooth glossy finish. Contrast refers to the number of grays given between white and black (a hard contrast gives few grays; soft contrast gives many tones of grays). Variable contrasts are also available. Contact printing can also be done on resin – coated paper that washes and dries faster but this type of paper is more expensive.
Enlargement Printing
After contact, printing enlargement has to be made whereby an enlarger is used. A good enlarger should be one that can be used for both black and white photography and in colored photography. It should have filter drawers for colored photographs. Enlargement allows several control over image; the negative can be printed to almost any size.
The choice of how light or dark the print should appear can be determined by the choice of exposure time. There is no limit to the number of identical prints that can be made from one negative. Black and white photographs can be made from colored negatives.
Contact printing and enlargement process requires a dark room, these is a room specifically designed for carrying out photo printing, they are supposed to be totally light tight, dust free, smooth plastered walls and without any shelves and any other wall fixtures because these may trap dust.
Its doors, frames, windows and ventilation grills should be light tight, should instead be provided with artificial air conditionings that are light tight, electric power and water .its floors should be made of chemical resistant materials.