Scene: The race course. The first race of the day is heading for a nail-biting finish. Excitement mounts as the galloping horses round the bend and hurtle towards the finishing post.In the little room above the Grand Stand in the First Enclosure, the tension is palpable as Rudolf D'Costa trains his eyes on the horses, now barely five feet away from the end of the race. He deftly switches on the motor of the camera. Once the horses go past the camera lens, D'Costa and assistant Santosh Pillai work like men possessed. Shutters come down, the negative is disengaged from the camera, dunked in various solutions, a print is made and the photograph is sent to the judge sitting below. It takes precisely four minutes - four crucial minutes that will decide the winning horse.``It is a thrilling job but one we perform under tremendous pressure. There are no retakes in a race,'' says D'Costa, photographer at the Royal Western Indian Turf Club's (RWITC)'s photo finish department at the race course for the past nine years. And he would not have it any other way. ``After all, we are the first ones to know the result of the race in case of a photo finish''.Preparations start two days before a race. ``As the camera plays such a decisive role, it is essential to align it with the winning post. A cotton belt is put across the tracks from the centre of the post, which has a mirror attached to it, to the railings right in front of the judge's post. The reflection of the belt in the mirror is aligned with the camera,'' says D'Costa. The rotor below the post, which displays the number of the race and the date on which it was held, is set from the photo finish department.A specially-assembled electrically-operated camera with an aperture of 0.3 mm is used. A few minutes before the race is to begin, the film, a Kodak T-Max, is tightly wound round the motor in the camera and held in place with pins. The motor is switched on moments before the horses reach the finishing post, and it moves in the clockwise direction, recording the horses moving in the anti-clockwise direction. Whatever passes before the camera at a particular speed gets recorded onto the film.``While every race is photographed, only those that end in a photo finish get developed,'' says Pillai. In the event of a photo finish, the judge communicates this via the telecom to the photographers, who work in tandem. All light is blocked out as the negative is disengaged from the motor and put into the developing and then the fixing solution. During printing, the negative is put into an enlarger while the printing paper is affixed to a frame with a metal wire across it. This artificially creates the impression of the finishing line and is later reproduced in the photograph.``The photograph is then passed on to the judge and is later displayed on the closed circuit camera and the bulletin board,'' explains D'Costa.While the duo admits that there have been many nervous moments, there have been no mistakes, the two claim. ``We cannot afford to make mistakes. When I was new at the job, I remember an exciting Derby race during the Mumbai season, which culminated in a rare dead heat. I was extremely nervous then but everything turned out fine,'' he recalls.After the Pune racing season from July to October, the photographers move to Mumbai for the season from November to April. While the weekends are exciting, what with races on, during weekdays, the two stick to routine administration work. And no, they do not bet on the horses. Says D'Costa, ``We would lose the most important factor in the job - concentration!''