electronic flash
Quick Summary
Electronic flash, also known as a flashtube or speedlight, is a photography tool that provides a brief, intense burst of light. It works by discharging high voltage through a gas-filled tube, typically containing xenon. This ionization causes the gas to flash, creating a light duration as short as one microsecond.12
This technology allows for synchronized, high-intensity lighting for photography, enabling clear images of fast-moving subjects or dimly lit scenes. Modern electronic flashes can be built into cameras or used as external units, with some featuring automatic exposure control that adjusts flash duration based on reflected light. While flashbulbs were an earlier form of flash photography, electronic flash has largely replaced them due to its convenience and reusability.3245
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technology of photographyElectronic flashThe most common flash system depends on a high-voltage discharge through a gas-filled tube. A capacitor charged to several hundred volts (by a step-up circuit from low-voltage batteries or from the line voltage supply) provides the discharge energy. A low-voltage circuit generating a…
Read MoreThe most common flash system depends on a high-voltage discharge through a gas-filled tube. A capacitor charged to several hundred volts (by a step-up circuit from low-voltage batteries or from the line voltage supply) provides the discharge energy. A low-voltage circuit generating a…
Read More- technology of photographyFlash exposures
Most current electronic flash units incorporate a sensor cell that measures the light reflected from the subject and controls the flash duration (and hence the exposure) accordingly. In certain cameras in which photocells measure the light reflected from the film, the same cells can similarly control the…
Read MoreMost current electronic flash units incorporate a sensor cell that measures the light reflected from the subject and controls the flash duration (and hence the exposure) accordingly. In certain cameras in which photocells measure the light reflected from the film, the same cells can similarly control the…
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