A useful mode if you’re shooting in a theatre or museum, but one that’s only available on compact cameras with in-lens shutters and mirrorless cameras with electronic shutters. On compact cameras you can get the same effect by turning off the focus ‘beep’ and shutter sounds.
This is a big topic! It hardly needs saying that cameras are complex in design terms and filled with complex technology too. Inevitably, then, this list of topics related to camera features is very long indeed and extends over several pages.
The length of time the shutter is open during the exposure and usually quoted as fractions of a second. Each shutter speed is half as long as the one before, for example 1/30sec vs 1/60sec. This exposure ‘halving’ is the basis for balancing up lens aperture and ISO settings. A few cameras have external shutter speed dials but most simply display the shutter speed on the LCD display – you turn a control dial to change the speed.
Exposure mode where you choose the shutter speed and the camera selects a lens aperture to give the correct exposure. You get to choose the shutter speed manually, but the camera still takes care of the exposure automatically. On Canon cameras this is called Tv (time value) mode.
The mechanism that control the length of the exposure. On some smaller cameras this may be in the lens (a ‘leaf’ or ‘in-lens’ shutter), but on DSLRs and mirrorless cameras with interchangeable lenses, it’s a ‘focal plane’ shutter directly in front of the sensor.
The camera waits for a set delay before firing the shutter. This gives the photographer time to get in position for a group shot – but it’s also useful for tripod shots or long exposures where you want to fire the shutter without jogging the camera.