Shutter speed
As shutter speed, the exposure time is referred to, which is formed by a camera shutter. The control is either purely mechanical or electronic.
Technology
The usual shutter speed range is halved at each step, the adjustment period, which is exposed on digital cameras from the incident light, the photographic film or image sensor. The time indicated on the Verschlusszeiteneinstellrad a camera are given in reciprocals ( denominator of the fraction ).
It follows for example, the following time series in a split second:
At each stage of this time series, the amount of light that exposes the film in half. Shorter exposure times can be compensated by larger apertures ( = smaller f-number), this corresponds to a stage in the dazzling array of one stage of the time series.
Cameras with electronic shutter can one dear various other exposure times in comparison to the classical speed and aperture rows. In addition to shorter and longer shutter speeds in particular can frequently even intermediates in half or thirds f-stops can be set manually, in automatic operation practically infinitely variable settings are possible.
Simple camera equipped models with automatic programs each showing electronically selected time / aperture combination often to no more.
An old cameras and shutter lenses often find this series:
Even the shortest adjustable time may vary and, for example, 1/ 200 sec or 1/ 300 s amount.
Designations
Depending on the camera shows the Verschlusszeiteneinstellrad or display the shutter speed special designations:
- CAR represents auto exposure, so that the camera controls the exposure as a function of the diaphragm. For cameras without Verschlusszeiteneinstellrad this feature from the exposure program (usually " P", " A", " S", " M" or " P", " Tv ", " M", " Av " ) is set.
- B ( Bulb ) allows long exposures and opens the shutter as long as the shutter button is pressed. With electronically controlled cameras this setting is often only in manual mode "M" available (rarely also in shutter priority "S").
- T (Time ) enables similar to 'B' long-term exposures, while the shutter is opened at the first pressure on the shutter release and only closed when re- press of the shutter. Such a position of the Zeitenrads is only offered by a few older cases.
- X or a lightning flash ( in some camera menus using X - Sync called ) stands for the flash sync speed. For cameras with focal plane shutter, this is the shortest exposure time in the film or sensor is a moment long completely illuminated. At this moment, the flash fires (with TTL flash metering the main flash). For shorter exposure times of the 2nd shutter curtain starts running and already covered back parts of the film / sensor, although the first curtain has not yet expired and, therefore, portions of the film / sensor have not been exposed. Usual values for the flash sync speed is 1/60 - 1/ 300 s depending on the camera model, shorter values are achieved by multiple flashes ( high speed sync ). In a few older electronically controlled camera models the shortest X - sync speed is set automatically.
Conversion factor shutter speed and aperture setting
If an extension of the exposure by 3 levels is indicated, for example, a filter, then this corresponds to the extension by three notches on either the aperture ring or on Verschlusszeiteneinstellrad. An extension factor is applied to the exposure time. Following relationship exists between elongation factor and notches:
Image effect
The choice of shutter speed in addition to setting the correct exposure as well as the choice of orifice large influence on the image effect. With a high shutter speed to fast movements are "frozen ", a relatively long exposure time makes it possible to dynamically represent movements by blurring. Such effects are not to be confused with shake.
- Image design with different shutter speeds
Long exposure time
A small waterfall