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Projection Printing - 14209_292
Condenser Enlargers

Photography (Basic) - Introduction to photography and other graphic techniques
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enlarged the same size as the negative image or reduced in size. When the print images are larger than the negative images, the process is called enlarging. When the print images are smaller than the negative images, the process is called reducing. Because projection printing is usually used to make positive prints with images larger than the negative, projection printers are referred to as enlargers. The term enlarging generally refers to all forms of projection printing. Projection  printing  differs  from  contact  printing because the negative is separated from the paper, and the image is projected by a lens onto the sensitized material The negative is placed between an enclosed light source and a lens. The lens receives the light that passed through the negative and projects the image onto the paper. Changing the distance between the lens and the paper controls the size of the image. The image is focused  on  the  paper  by  adjusting  the  distance  between the negative and the lens. You can enlarge or reduce the size of the projected image by changing and adjusting these  distances. Enlarging  is  a  very  adaptable  and  versatile  process, because considerable image and exposure control can be used. The main advantage of enlarging over contact printing is large prints can be made, but there are several other   important   advantages.   The   advantages   of projection  printing  are  as  follows: Cropping or selecting the main area of interest in a negative can be enlarged to any suitable size. This provides an opportunity for you to eliminate unwanted and distracting elements from around the point of interest  of  the  picture. Dodging or burning in. This allows you to apply local exposure control to bring out more detail in the highlight  and  shadow  areas. Local fogging with a small external light, such as a penlight, to darken selected areas; for example, by darkening the background of a portrait, you direct the viewer’s  attention  to  the  face. Special  effects  can  be  performed,  such  as changing the appearance of the image by use of diffusers or  patterns  between  the  lens  and  paper. Image  distortion  correction  or  introduction  can be done by tilting the enlarger easel. (An easel is the device used to hold the paper during exposure.) Figure 11-7.–Basic enlarger. ENLARGERS In general, all enlargers are similar in design and operation. They have an enclosed light source, some method of providing an even distribution of light over the negative, a negative carrier, a lens, a means of adjusting  the  lens-to-negative  and  lens-to-paper distances (fig. 11-7). The degree to which the image is enlarged can be referred to in terms of diameters; for example, a two diameter or 2X enlargement is twice the length and twice the width of the negative image, or four times the area A three diameter or 3X enlargement is three  times  the  length  and  width  of  the  negative  image, or nine times the area. Most enlargers have a tungsten lamp as a light source. The lamp is enclosed in a lighttight housing that is ventilated to prevent excessive lamp heat from damaging the negative. Some enlargers have blowers to circulate air and cool the inside of the lamp housing. The negative carrier used in an enlarger may be either a dustless type or a glass sandwich type. The dustless type of carrier is made of two metal plates with an opening in the center large enough to hold the negative. The negative is placed between these plates and held in position by its edges. This type of carrier is good for negatives 4x5 or smaller, since these negatives are stiff enough to remain flat. The glass sandwich type 11-9







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