اللوازم الأساسة الواجب توافرها في الحجرة المظلمة .. كتاب أسس التصوير الضوئي

Basic supplies to be available in the darkroom:

(1) Devices for measuring time and temperatures:

Modern display methods do not rely on guesswork, but rather depend on the necessity of measuring the temperature of the display solution and estimating the time required for display based on knowledge of the temperature of the solution. As we will see later, the temperature of the exposure solution has a significant impact on estimating the time required for the exposure process. Therefore, there must be thermometers available in the imaging laboratory to measure the temperature and means for timing. The timing means required for the imaging laboratory are multiple and in different forms, and here it suffices to point out that some of them can be set to a specific time, such as several minutes, for example, and at the end of the display time, the alarm bell rings. Others paint their numbers and hands with a phosphorescent habit that glows in the dark. Timing devices are also necessary for the printing and enlarging operations necessary to produce the positive image. Some of them are equipped so that they are connected to the light sources in the amplifier or the printing device with electrical connections in a way that stops the exposure to the light after a certain time, if the necessary exposure time does not exceed a fraction of a second:

(2) Supplies for drying negative and positive films:

Perhaps the best way to dry sensitive negative films and plates is to use the drying wheel prepared for this purpose.

The electric fan may be located at the top or bottom of the cupboard, and as an extra precaution to prevent any dust from reaching sensitive films or panels before they dry, a piece of tight cloth is placed in front of the fan to prevent any dust from leaking out. These wheels are usually equipped with metal clips for hanging films and other heavy clips to be attached at the bottom. Films to simplify and prevent curvature. As for the drying of sensitive papers, another special dryer is needed, whose temperature rises to a relatively high degree sufficient to dry and spread the sensitive papers. With this type of dryer, glossy plates are used to polish the sensitive glossy paper, and they are called Ferrotype Plates.

In order for the images to be highly polished, a polishing solution is used that can be purchased prepared and is called a glazing solution. It is used to dip the images in it before drying them, then the drying process takes place in the usual ways. If it is not possible to obtain a dryer for paper, some follow an easy method that we show in (Fig. Drying it, by passing the paper on the edge of a right-angled table with light pressure with the left hand, and this method requires a little practice and can be considered very useful if mastered.

(3) The enlarging device for positive images, and we will talk about it in detail in the section on positive images.

(4) Contact Printing Fund, and we will talk about it in detail in the section on positive images.

(5) A box for printing written documents or papers, and we will talk about it in detail in the section on positive photos.

(6) Special scissors for cutting sensitive papers or the edges of positive images after drying them.

(7) Measurements for estimating the appropriate time for exposing photosensitive paper, and we will come back to talk about them in detail.

(8) Glass containers, jars for preserving salts, graduated cups for installing solutions, bottles for preserving solutions, accurate scales for weighing salts before mixing, a funnel, a glass stick for stirring, etc.

(9) Duct basins for displaying, fixing, washing, etc. operations.

(10) A special heater to raise the temperature of the solutions in the iron pans when working. winter - and a refrigerator to cool the running water - if possible - to cool the highlighting solutions in summer.

(11) Tanks for display operations, whether they are intended to be built in the dark room or intended for display operations in daylight.

(12) Receptacles for dumping waste. This has been carried out by many designs of dark rooms in different forms and with varying costs, and we quote below the design of the two sides of a dark room quoting a design by Kodak. (Fig. 93).