صيانة المكبر .. كتاب التحميض والطبع والتكبير

Amplifier maintenance:
(a) Always improve its coverage after use.

(b) The column on which the set of basic parts slide between the lighting - the negative holder and the stapler should be lubricated from time to time, provided that it is well cleaned prior to this process to get rid of any dust that may be attached to it.

(H) Clean the lens with a soft brush, without rubbing vigorously.

(E) Always take care to clean the holder of the negative images prior to placing the negative image.

Lighting house:

The light house in the amplifier is one of the following forms:
(a) Direct illumination with condenser
The light source is a tungsten lamp that emits rays that pass first through a photocondenser and then to the negative. The light intensifier in many magnifiers consists of two combined lenses, each of which is convex on one side, while the other side is a Plano-Convex space that is placed in the magnifier so that the two flat faces are facing outwards, while the two convex faces are opposite each other (Fig. 9 H B S H). Here we may wonder about what calls for making the light detector in the previous form, without being satisfied with a single biconvex lens on both sides, as shown in (Fig. 159), and in response to that we say: Although it is both of two types. By collecting light rays, however, the first type consisting of two lenses is distinguished from the second by its superior ability to benefit from the maximum amount of light emitted by the source.

(b) Diffused light whose source is an opaque white lamp whose rays pass through an opaque white opal glass (Fig. 160).

(h) The illumination in the magnifier may be arranged in the two previous ways together, in the sense that the rays pass through the optical condenser first and then through the white opaque glass secondly before heading towards the lens.

(e) The illumination may be indirect, as the light rays exit from the lamp and are covered by a mirror (Figure 62) or reflected by a white or silver surface (Figure 63). The reflected light rays may pass through a light condenser (as shown in Figure 62). This method is characterized by its ability to reduce the effect of the heat of the electric lamp on the negative image directly.

And whether the lighting is prepared in a certain way or another, the basic condition in the magnifier is that the light comes out completely distributed evenly, evenly illuminated on all parts of the negative, and its quantity is greater in one corner or in the middle than any other part, and the final result that we get differs from one negative that was enlarged in two magnifiers The first works with a condenser, and the second works with opaque white glass, as the degree of contrast increases in the positive image if the magnifier has a condenser. It is disposed of if the light is distributed. Figure 64 p. 295 p. Figure 83 p. 323 6 p. Which is sometimes found in the negative image as a scratch, dust, or otherwise. For this reason, it is not desirable to use an amplifier with an internal capacitor if any repairs are made on the negative (Retouching). The lighting house is also equipped with a means of ventilation so that the heat of the lamp does not affect and damage the negative image.