التصوير مع الفلاش .. المصباح الومضي .. كتاب فن التصوير الفوتوغرافي

Photography with flash, flashlight

Photography with a flash or flashlight is the most used way to take a picture in the dark because it is easy to use and moderate in price.
However, its use does not depend on photographing in the dark, but it is also used as an auxiliary light in daylight to reduce the sharpness of the shadows.

Flash types

There are two types of flashes: the first is the regular flash bulb, which is used once and is thrown away, and the electronic flash, which is a gas-filled tube through which a strong electrical charge passes, causing a strong light explosion that lasts a fraction of a second.
Both types are used in the same way.

Flash bulbs

It is a glass lamp containing a metal strip coated with fast-flammable powder. The lamp is full of oxygen. When an electric current from a battery passes through it, the tape heats up and the powder and tape burn, generating an intense light that lasts a fraction of a second.

Types:

There are many types of flashlights for a variety of uses. They differ in the amount of light that they emit, the length of the period during which they radiate, and the period of time required between the passage of the electric current and the occurrence of the light explosion, and all of these are important factors that determine the proper use of the lamp. Some of these lights burn quickly, and are designed for the simplest cameras without precise synchronization between light and shutter speed. Some of them burn less quickly and get, through their slow burning, a very short exposure of the film. This type requires precise synchronization between the combustion period and the opening of the moving curtain.

The intensity of the light produced by the lamp is measured by a unit of measurement which is (Lumen), just as the amount of light emitted by a lamp is measured by the amount of (Lumens) that it emits during the entire period of its ignition. Another important characteristic of each lamp is the intensity of its light at its peak.
It reaches this peak some time after the electric current is connected, as the curve rises until it reaches the peak and then returns to the decline until it fades away.

The types of lamps are classified according to the time required for them from the moment the current is connected until the light reaches its peak. For most of them, this time is just under 20 thousandths of a second, or 1/50th of a second.
The main types are: fast peak, M2, AGL, M25, medium speed peak (M), slow peak (S), and very slow peak (FP).