RaceTech has long been a world leader in the field of photofinish technology. It is with the photofinish that the company began, and it remains in the vanguard of research and development of a process crucially important to other sports as well as horse racing: technology based on the racing model has long been in operation at top athletics meetings, including the Olympic and Commonwealth Games.

The photofinish has been an integral part of the racing and betting experience for decades, and the technology is constantly evolving. Time was when punters would have to endure an agonising few minutes suspended in that frozen state before the result was announced. Today the process is so efficient and slick that the verdict is given within seconds.

The ability to provide an objective and rapid pronouncement about which horse's nose is in front on the line is a basic requirement of modern racing - and not just to still the beating hearts of connections and punters: the rate of turnover in betting shops, claim the bookmakers, depends on punters knowing their fate as quickly as possible, so that those who have won can reinvest without delay and those who have lost can adjust their staking plan for the next race.  Although the photofinish is where RaceTech began life back in the 1940s, the modern procedure for photographing horses as they cross the finish line is a far cry from the early methods, and it is only comparatively recently that the fully computerised photofinish system - Scan-O-Vision - has been in widespread use.

The fundamental principle is the same as before – photographing runners as they pass through a very narrow field of vision - but the technology, once based around a spool of continuous moving film, is now state-of-the-art. Two digital cameras are fixed in place in the photofinish booth high in the stand - one to cover the whole width of the track and the other to focus on that part of the course furthest away from the camera in order to make maximum use of the strip of mirror (1800 mm x 150 mm) attached to the winning post. This allows the Judge to see what is happening from the far side of the course if the horses are so close together that the view from the Judge's box does not afford enough information.

The pictures these cameras produce are made up of millions of tiny dots known as 'pixels', and a vertical line of these dots photographs the activity on the winning line up to 2,000 times a second, building up the photofinish picture as the horses go through.

To accommodate racecourses with wider home straights, in 2009 Racetech introduced a new photofinish system which utilises an infield camera to replace the mirror camera. This provides the Judge with a clearer image of finishing horses further away from his viewing position.

In the old days film had to be processed before the Judge could deliver his or her verdict. Now the Judge simply has to examine the image, which is instantly presented on the monitor, with a vertical white line added to represent the winning line. The aim is to announce the result of the photofinish within twenty seconds - compared with several minutes under the old system. Not that the old system did not enjoy a long and honourable life.

The prototype photofinish camera - based on the notion of photographing moving objects through a slit onto a continuous strip of film - was first used to decide placings in the Grand Metropolitan Handicap at Epsom on 22 April 1947: the winner Star Song was a length to the good, but the Judge needed to consult the photo before deciding that Parhelion was second, a head in front of Salubrious. In the 1948 season a photograph was called upon to decide the outcome of horse races on 119 occasions, and the same year photofinish technology was used for the first time in the Olympic Games, held in London.

The following year a photo was first called upon to decide the outcome of a Classic race in England when Nimbus beat Abernant a short head in the 1949 Two Thousand Guineas at Newmarket.  Later the same season it was first used to determine the outcome of the Derby, when the Judge called for the evidence of the camera before announcing Nimbus the winner by a head from Amour Drake, with Swallow Tail another head away in third. Before long the photofinish became an accepted - indeed, an essential - part of horse racing, and its regular use spread to other sports (notably greyhound racing, trotting, cycling, athletics, even speed skating) which involve the likelihood of very close finishes.

Photofinish technology was originally based on a simple idea but now, as in so many other areas, the mind-boggling capabilities of computer technology have been deployed to transform the whole business. And with sixteen complete kits in use, RaceTech is ensuring that the photofinish system on British racecourses is at the very forefront of technology.