أجزاء آلة التصوير.

Camera parts

The photocopier consists of main parts that must be available in every machine, in addition to other parts that are considered improvements that may exist in some types over others, either fixed in it or attached to the machine. The reference for studying these parts is a correct study, and there is no problem in examining and using them. Therefore, we will list a brief statement of these parts, and we will come back to study them extensively. First: the basic parts

(1) The lens: It is the glass part that collects the rays to record them on the sensitive layer (and we will come back to talking about it extensively).
(2) Diaphragm, and some call it the pupil due to its similarity in function to the pupil of the human eye - it consists of thin sheets overlapping each other in Figure (3). Its function is to determine the width of the aperture through which the rays pass into the sensitive layer, and accordingly it controls the amount of light that is allowed to enter the camera. Appended to the diaphragm are numbers symbolizing the ability of the lens to receive light whenever its opening narrows or widens, for example 22 - 16 4 - 11 4 - 8 - 6 and 45 - 44 - 8 and 12 - (Fig. 4) and we will return to explaining what these numbers are when speaking on the camera lens.

Indication of the numbers indicating the opening of the diaphragm, and by moving the gear on which these numbers are shown, the opening of the diaphragm can be reduced or enlarged.

(3) The expensive or the shutter

And it is between the lenses that controls the time during which light is allowed to pass through the lens to the sensitive layer, and this time may be, for example: from a second, or not, or by it, or ... etc... The shutter is placed in the camera in one of the following places:

A - Between the lenses, in most of the good types.
B - just in front of or behind the lens (fig. e) ed and is usually found in primitive or simple types.

C - In the back, directly in front of the sensitive layer, and by means of it, very high speeds can be obtained, which may reach a lim of a second. This type is found in the most expensive types of cameras and is called the Focal Plane Shutter.
The numbers denoting the shutter speed are appended with the letters T and B.

The shutter is set at one of these two speeds in cases where it is necessary to increase the exposure time from one second, and the letter B stands for Brick Time Exposure, and by pressing the trigger, the shutter opens, then closes as soon as the pressure is lifted from the trigger. The letter T: stands for Time Exposure. By pressing the trigger, the shutter opens and remains open despite letting go of the trigger, and it remains open until the trigger is pressed again. The speed T is used when it is necessary to expose the sensitive film for a long time, from five seconds, for example, to much more than that (10 minutes, for example, or more).

(4) View Finder, some call it a viewfinder or viewfinder. It is a means of determining the area within the scope of the lens's vision. The shape of the viewfinder differs according to the different types of cameras. It may consist of two lenses, the most important of which are perpendicular, and between them is a mirror whose surface is at an angle of 45 with the axis of each of the two lenses (Fig. 16), or the viewfinder that will be photographed is determined by frosted glass.

At the top of the camera, as is the case in the reflex species, or by any of the means shown in (Fig. 6). Method for adjusting the distances: The method for adjusting the distance differs in different cameras, and they all boil down to moving the lens forward or backward until the image becomes sharp.

The distance on the camera is set in one of the following ways:

A - Using the numbers shown on the camera, based on an estimate of the visual distance (Fig. 7).

B - By means of a distance measure called the Telemeter whose image is shown in Figure 7 (b)) and its purpose is to measure the distance and then adjust it by means of the numbers shown in “a”.

C - Or through the so-called Coupled Range Finder, where a double image appears in the place of the circle, and by moving the lens, the distance becomes set when the two images coincide completely (Fig. 7 (c)).

d- Or the distance can be set directly by ground glass, if the camera is prepared for that.