- published: 14 Jan 2016
- views: 373361
A photo finish occurs in a sporting race, when two (or more) competitors cross the finishing line at near the same time. As the naked eye may not be able to discriminate between which of the competitors crossed the line first, a strip photo, a series of rapidly triggered photographs, or a video taken at the finish line may be used for a more accurate check. Nowadays, the photographs may be digital. A digital photo finish camera uses a 1-D array sensor to take sequential images of the finish line. Since only a single line of the CCD is read out at a time, the frame rates can be very high (up to 10,000 frames per second). Unlike a film based photo finish, there is no delay from developing the film, and the photo finish is available immediately. They may be triggered by a laser or photovoltaic means.
Historically, a hand cranked strip photograph was taken at the finishing line. Today, finish-line photos are still used in nearly every modern racing sport. Although some sports use electronic equipment to track the racers during a race, a photo is considered the most important evidence in selecting the winner. They are examined not only when a race is close or when a record has been broken, but are often used to give official times for events. An alternative is the use of manual touch pads to register a time by the athletes themselves, such as in competitive swimming.