photography Photography is the visual arts, art, application, and practice of creating images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is empl ...

, shutter lag is the delay between triggering the shutter and when the

photograph A photograph (also known as a photo, or more generically referred to as an ''image'' or ''picture'') is an image created by light falling on a photosensitivity, photosensitive surface, usually photographic film or an electronic image sensor. Th ...

is actually recorded, which includes all lag between when the shutter button is pressed and when the photo is taken, including metering and focus lag. it can be mitigated to an extent by pre-focusing and readying for action.

Film cameras

In film cameras, the delay is caused by the mechanism inside the camera that opens the shutter, exposing the film. Because the process is mechanical, however, and relatively brief, shutter lag in film cameras is often only noticeable (and of any concern) to professionals. SLRs have a slight additional lag due to the time it takes to move the mirror out of the way.

Digital cameras

Shutter lag is much more of a problem with

digital camera A digital camera, also called a digicam, is a camera that captures photographs in Digital data storage, digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film or film stock. Dig ...

s, although higher cost models tend to have less lag. The comet-tail artifact that early CCD sensors suffered from was significantly reduced by the invention of the pinned photodiode (PPD). It was invented by Nobukazu Teranishi, Hiromitsu Shiraki and Yasuo Ishihara at

NEC is a Japanese multinational information technology and electronics corporation, headquartered at the NEC Supertower in Minato, Tokyo, Japan. It provides IT and network solutions, including cloud computing, artificial intelligence (AI), Inte ...

in 1980. The "pinned photodiode" is a

photodetector Photodetectors, also called photosensors, are devices that detect light or other forms of electromagnetic radiation and convert it into an electrical signal. They are essential in a wide range of applications, from digital imaging and optical ...

structure used in almost all charge-coupled device (CCD) and CMOS image sensors (CIS) due to its low

noise Noise is sound, chiefly unwanted, unintentional, or harmful sound considered unpleasant, loud, or disruptive to mental or hearing faculties. From a physics standpoint, there is no distinction between noise and desired sound, as both are vibrat ...

, high quantum efficiency and low dark current. In 1987, the PPD began to be incorporated into most CCD devices, becoming a fixture in consumer electronic video cameras and then digital still cameras. The PPD has since been used in most CCD sensors and then

CMOS sensor An active-pixel sensor (APS) is an image sensor, which was invented by Peter J.W. Noble in 1968, where each pixel sensor unit cell has a photodetector (typically a pinned photodiode) and one or more active transistors. In a metal–oxide–semic ...

s. Improvements in technology, such as the speed, bandwidth and power consumption of processor chips and

memory Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembe ...

, as well as CCD technology and then CMOS sensors, have made shutter lag less of a problem. While digital SLRs have achieved lag times around 50 ms by the late 2000s, some

EVIL Evil, as a concept, is usually defined as profoundly immoral behavior, and it is related to acts that cause unnecessary pain and suffering to others. Evil is commonly seen as the opposite, or sometimes absence, of good. It can be an extreme ...

s take half as long in the 2010s. That said, the lag times of some exceptional historic devices are still unsurpassed, see table below.

Examples of various shutter lag times

Note that cameras offer increasingly varied choices of fully mechanical shutter, first-curtain electronic shutter (EFCS; meaning a mechanical shutter only at the end of the exposure), or fully electronic (thus silent) shutter. This is paired with either autofocus, fully manual focus, or prefocus (half-pressing the shutter button to engage autofocus and lock exposure; then holding the button half-pressed until the decisive picture-taking moment, in which the button is depressed completely). Typically, prefocus + EFCS results in the shortest shutter lag (see the following individual sources with measurements for all available modi). This table quotes the shortest possible lag time of the respective camera. Note that variations may occur between manufacturer-claimed times and real-world measurements. In the case of follow-up versions of cameras (Mark II, -N, -s, ...), it is usually save to assume identical performance unless explicitly stated otherwise in press releases or comparisons.

References

Josef Scheibel, Robert Scheibel: ''Foto-Guide Minolta Dynax 9''. vfv Verlag für Foto, Film und Video, Gilching 1999, {{ISBN, 3-88955-116-5 (176 pages

retrieved at 8 January 2011). Imaging-Resource Preview Sony Alpha SLT-A77V
/ref> Imaging-Resource Preview Sony Alpha NEX-5N
/ref> Imaging-Resource Preview Sony Alpha NEX-5
/ref> Imaging-Resource Preview Sony Alpha DSLR-A900
(Firmware 1) Imaging-Resource Preview Sony Alpha DSLR-A850
(Firmware 1) Imaging-Resource Preview Konica Minolta Dynax/Maxxum/Alpha 7D
/ref>

External links

Shutter lag comparison chart for digital P&S

Imaging Resource camera reviews often with measured shutter lag times

What is Zero Shutter Delay (ZSD) on your mobile camera
Photography equipment