Bulb (photography)

Bulb (photography)

Bulb is a shutter-speed setting on an adjustable camera that allows for long exposures under user control. When set on "B", the shutter will stay open as long as the shutter release button remains depressed. The "T", or Time, setting, on the other hand, requires one press to open the shutter and a second press to close it.

History

The term "bulb" is a reference to old-style pneumatically actuated shutters; squeezing an air bulb would open the shutter and releasing the bulb would close it. According to the Focal Encyclopedia of Photography ["Focal Encyclopedia of Photography", Frederick Purves (editor), London: Focal Press Ltd., 1956.] ::"BULB EXPOSURE (B). Another term for a brief exposure—in which the shutter remains open only so long as the shutter release is held down. The word originated with the early pneumatic shutter release."

It is not clear when the term actually originated. It appears that when "instantaneous" shutters were introduced, they included a B setting so that the familiar "bulb" behavior could be duplicated with a cable release. This may have been the origin of the term "bulb" in reference to shutter settings. See the photo captions.

Uses

The bulb setting is usually used for exposures with a duration longer than a few seconds or even longer than the 15 second setting that is the maximum setting possible with some cameras' shutter settings.

On many digital cameras, the bulb-mode will be accessible from the LCD menu only, if possible at all. As a rule of thumb, SLR cameras do have a bulb setting and compacts do not have one. A few bridge cameras such as the Olympus SP-560UZ have a 'limited' bulb setting, allowing time exposures up till 8 minutes and at an ISO setting of 200 ISO and lower.

Because of the risk of camera movement, the camera is most often mounted on a tripod for the duration of the exposure. To further reduce the risk of camera shake, the camera's shutter is triggered by the use of a cable release or electronic remote. The cable release often has some kind of lock that can be used to keep the shutter release depressed for the duration of the exposure.

A list of picture types where the bulb setting is useful:
* Photographing fireworks at night
* Photographing the night sky and celestial objects.
* Photographing lightning
* Photographing streets at night (where the streaks from moving cars lights can be seen, not the cars)

References


Wikimedia Foundation. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • Bulb (disambiguation) — A bulb is a 3 dimensional shape made by connecting a rod to a sphere.Bulb may mean: * Bulb, a part of a plant. * Light bulb, a source of electric lighting. * Flashbulb, a bright, rapid lightbulb. * Bulb (photography), a shutter setting. * Bulbous …   Wikipedia

  • photography, technology of — Introduction       equipment, techniques, and processes used in the production of photographs.  The most widely used photographic process is the black and white negative–positive system (Figure 1 >). In the camera the lens projects an image of… …   Universalium

  • Exposure (photography) — Underexposure redirects here. For the 2005 film by Oday Rasheed, see Underexposure (2005 film). A long exposure showing stars rotating around the southern and northern celestial poles. Credit: European Southern Observatory …   Wikipedia

  • Wedding photography — photography is a major commercial endeavor that supports the bulk of the efforts for many photography studios or independent photographers.History.) Due to the nature of the bulky equipment and lighting issues, wedding photography was largely a… …   Wikipedia

  • Flash (photography) — The furious wing action of a Hummingbird Hawk moth is frozen by flash. The flash has given the foreground more illumination than the background. See Inverse square law A flash is a device used in photography producing a flash of artificial light… …   Wikipedia

  • Night photography — The Night Sky Photographed facing north at 6600ft in the Mt Hood National Forest …   Wikipedia

  • Incandescent light bulb — The incandescent light bulb, incandescent lamp or incandescent light globe is a source of electric light that works by incandescence, (a general term for heat driven light emissions which includes the simple case of black body radiation). An… …   Wikipedia

  • Reflector (photography) — In photography and cinematography, a reflector is an improvised or specialised reflective surface used to redirect light towards a given subject or scene. Types Apart from certain highly specialized components found in enlargers, projectors and… …   Wikipedia

  • Reciprocity (photography) — In photography and holography, reciprocity refers to the inverse relationship between the intensity and duration of light that determines exposure of light sensitive material. Within a normal exposure range for film stock, for example, the… …   Wikipedia

  • Time Exposure (album) — For the photographic technique of time exposure see Bulb (photography). Infobox Album Name = Time Exposure Type = studio Artist = Stanley Clarke Released = Recorded = Genre = Jazz fusion Soul music Contemporary jazz Rhythm and blues Length =… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”