Photo Finish in Horse Racing: The Judge and Dead Heats

The horse whose nose reaches the winning line first wins the race. Not its leading foreleg, not its rider, not the peak of the saddle. When the judge in the box above the line at a British racecourse cannot separate the leaders by eye, the public address announces "photograph", the judge examines an image recorded by the photo-finish camera and calls the result from that. If the image cannot separate the noses either, the result is a dead heat and the horses share the placing, with the prize money for the shared places pooled and divided.

That is the short answer to how a photo finish in horse racing works. The judge is a British Horseracing Authority official, the camera has been used on British racecourses since 1947, and the smallest margin the judge can return is a nose. What follows is the detail behind each step: why the picture looks so strange, what the mirror is for, how a judge gets from an image to "short head", and what happens to a trophy, a prize fund and a jockey's tally when two horses tie.

Why the nose, and nothing else, decides a race

The nose rule is old and absolute. Racing has to measure the finish against something, and the nose is the leading point of a galloping horse for almost the whole of its stride. A foreleg reaches out and then comes back. A jockey sits behind the withers and may be up the neck or sitting back. The nose is there, at the front, every stride.

It also gives a clean, single point that the judge can read on an image. A vertical line laid over the photograph touches the tip of the nose and nothing else. Using a hoof would require the judge to decide which hoof and at what stage of the stride; using the rider would make the result depend on how far forward a jockey was pushing. Neither would be repeatable.

The nod

A galloping horse's head goes up and down with its stride. At full stretch the head and neck reach forward and down; as the legs gather, the head comes up and back. In a close finish, this rhythm decides races. Two horses that are stride for stride across the final furlong may finish with one at full stretch and the other at the top of its stride, and the horse at full stretch wins by a nose or a short head. Jockeys talk about "getting the nod". It is partly timing and partly luck. A good jockey tries to time the final push so the horse is reaching at the line, but in a desperate finish no rider controls exactly where in the stride the line falls.

How other sports draw their line

Comparing racing with other sports shows how much the choice of point matters. Track athletics decides a sprint by the torso, the trunk of the body, deliberately excluding the head, arms, hands and legs, which is why sprinters dip their chests at the line rather than lunging with an outstretched arm. Greyhound racing, much closer to horse racing in its logic, also reads the nose. Cycling uses the leading edge of the front wheel, which is why sprinters throw their bikes forward in the last metre.

Each of those rules picks a point that is always present and always at the front, and each produces its own finishing technique. The racehorse equivalent of the sprinter's dip or the cyclist's bike throw is the jockey's final push, trying to keep the head down and stretching at the moment the line arrives. The rule shapes the riding.

A hidden horse

The nose rule creates one practical problem. In a close finish, a horse on the far side of the track can be masked by the horse on the near side, so the judge cannot see the far-side horse's nose directly. That problem is what the mirror solves, as the following sections explain.

How the camera builds a picture from time

The photo-finish camera is not taking a photograph in the ordinary sense. It is recording a very narrow vertical slice of the winning line, many times a second, and stacking those slices side by side. The image that results has the line itself running across it, and the horizontal axis is time, not space.

1. 1AimThe camera is fixed on the exact line of the winning post, looking across the track
2. 2SliceIt records a narrow vertical strip of that line only, nothing either side of it
3. 3RepeatThe strip is recorded many hundreds of times a second as the horses cross
4. 4StackSuccessive strips are placed side by side, so the image shows time running across it
5. 5ReadEach horse appears at the moment its body crossed the line, nose first

The general principle of the line-scan camera used for finish recording; the equipment and frame rates used at British courses have changed over time.

Why everything looks strange

Because the camera only ever sees the line itself, anything that is not moving through the line appears as a smear or stripe. The background, the rail, the grass, the far side of the track: none of them pass through the line, so each one is recorded as the same thin slice repeated over and over, and stretches across the picture as a band. Horses do cross the line, so they appear as recognisable shapes. Their legs, however, are moving at different speeds from their bodies, so a leg that was moving forward while the body crossed may look stretched, bent or impossibly long.

Alignment before racing

All of this depends on the camera looking along exactly the right line. If it were angled even slightly away from the winning post, it would record a slice of track a little before or after the true finish, and in a race decided by a nose that error could change the result. The equipment is therefore set up and checked against the line before racing, and the mirror on the far side is aligned with it as well. The photo-finish system at British courses is supplied and operated by RaceTech, whose staff run the camera on the day, while the judge remains the official who reads the result. A misaligned camera is the kind of fault nobody would notice until a close finish exposed it, which is why the checks are routine rather than occasional.

Why the image is a record of time

The practical consequence is that each point along the image corresponds to a moment. The first nose to appear on the image is the first to cross the line. A horse that appears a little further along crossed a fraction of a second later. That is exactly what a judge needs. The image is not a picture of where the horses were at a single instant; it is a record of when each one reached the line, which is why it can separate horses that were never actually photographed together at the same moment.

The mirror on the far side and the vertical line

Opposite the camera, on the far side of the track, sits a mirror aligned with the winning line. The camera sees two images in one: the horses directly, from the stands side, and their reflection from the far side. A horse hidden behind another from the camera's angle is visible in the reflection.

That reflected view is what lets the judge see the nose of a horse on the far rail when a horse on the near side is masking it. The judge reads both views and checks that they agree. They always should, since it is the same moment seen from two sides, but the mirror is what makes the reading possible when horses are spread across the track.

Placing the line

To read the result, the operator or the judge places a vertical line on the image at the tip of the leading horse's nose. Anything behind that line has not yet reached the winning post at that moment. Moving the line to the nose of the next horse shows how far behind it was. In a close finish, the line is moved and checked repeatedly, and the image is magnified to see the exact point where each nose begins.

When the nose is hard to see

The photograph is not always clean. Rain, low light, mud on a horse's face, a white blaze against a pale background or a horse with its head turned can make the tip of the nose difficult to fix. The judge then reads the image with care, using both views and magnification. That is the honest reason some photographs take longer than others: not because the horses were closer, but because the image was harder to read.

The judge in the box above the line

The judge is a racing official employed by the BHA, sitting in a raised box on the winning line, usually on the stands side. The judge watches the race and, in the final furlong, concentrates on the line. When the finish is clear, the judge calls the placings by eye and confirms them with the image. When it is not, the judge calls for a photograph.

Announcing a photograph

The public address then announces a photograph, usually naming the horses involved: "Photograph between the second and fourth" or "photograph for first and second, also for third". The official result waits until the judge declares, and racegoers watch the big screen in the meantime.

How long a close one takes

A straightforward photograph is usually called within a minute or two. A very close one, or one where a horse's nose is hard to see, may take a few minutes more. The judge does not hurry. There is no time limit, and a result announced too early that has to be corrected is far worse than one announced a few minutes late.

What the judge declares

The judge declares the full result: the placings and the distances between each horse. The distances come from the image for close margins and from timing for wider ones. Once the judge has declared, the result can still be changed only in limited ways: by the stewards after an enquiry into interference or a breach of the rules, or by correction of a judge's error under the Rules of Racing. Stewards' enquiries are a separate process, set out in our guide to stewards' enquiries and how results are changed.

From "photograph" to "weighed in"

The judge's declaration is not quite the end. Before a result becomes official, the riders of the placed horses return to the weighing room and are weighed again by the clerk of the scales, to confirm they carried the weight allotted. If a rider is found to be significantly light, or fails to weigh in at all, the horse can be disqualified. Only when weighing in is complete, and no enquiry or objection is pending, is "weighed in" announced. At that moment the result is final for most purposes. A close photograph, a stewards' enquiry and weighing in can therefore all sit between the horses passing the post and the result standing, and on a busy afternoon a racegoer may wait several minutes for all three.

The order matters. The judge fixes the placings first; the stewards may then alter them; the clerk of the scales confirms the riders carried their weights; and the result is declared official.

Official	Role at the finish
Judge	Declares the order across the line and the distances between horses
Photo-finish operator	Runs the camera system and produces the image for the judge
Stewards	Hold enquiries into interference or rule breaches and may amend the placings
Clerk of the scales	Weighs riders in after the race before the result is made official

Nose, short head, head and neck: the margins a judge can return

The margins have a fixed vocabulary in British racing. The smallest is a nose, then a short head, then a head, then a short neck and a neck. Beyond the neck, margins are expressed as fractions of a length, starting at half a length, then three-quarters, then a length, then one and a quarter lengths and upwards.

Margin	What it means	How it is judged
Nose	The smallest distance the judge can separate	Read from the photo-finish image
Short head	Less than the length of a horse's head	Read from the image
Head	Roughly the length of a horse's head	Read from the image
Short neck	More than a head, less than a full neck	Read from the image
Neck	Roughly the length of a horse's neck	Read from the image
Half a length and beyond	Fractions and multiples of a horse's length	Converted from the time gap between horses

Those margins are anatomical: a judge looking at the photo-finish image can see whether the gap between noses is less than a horse's head, about a head or about a neck. They are not exact measurements. They are categories, and the judge places a gap in the category it most closely fits.

How the bigger margins are worked out

Above a neck, the margins come from time rather than from the image. The time gap between each horse crossing the line is converted into lengths using a scale set by the BHA, which takes account of whether the race is on the Flat or over jumps and of the going. On fast ground horses are covering more distance per second, so the same time gap converts to more lengths. What a length actually represents, and why it is not a fixed number of feet, is covered in our guide to the furlong and the racing length.

The shortest winning margin

The nose is the shortest winning margin in British racing. It is not a measurement but a declaration that the horses were separated by the smallest gap the judge could see. Below that, the only possible result is a dead heat. A winner by a nose has won as clearly, in the record books, as a winner by twenty lengths.

Dead heats, for first place or any other

A dead heat is declared when the judge cannot separate horses on the photo-finish image. It does not mean the horses were mathematically identical; it means no difference was visible on the best evidence available. The rule applies to any placing, which surprises some racegoers who assume only a winner can tie.

1. 1Photograph calledThe judge cannot separate the horses by eye and examines the image
2. 2No separationThe image shows no difference between the noses
3. 3Dead heat declaredThe horses share the placing, for example both are declared first
4. 4Next horseThe following horse takes the placing after the shared ones
5. 5Prize money pooledThe prize money for the shared places is added together
6. 6Equal divisionThe pooled sum is divided equally between the connections of the tied horses

The sequence under the BHA Rules of Racing for a tie on the line. Bets are settled under separate rules not covered here.

Ties for minor places

A dead heat for second, third or fourth is more common than one for first, because there are more places at which to tie and because a judge is looking at a crowded image when the minor placings are close. A dead heat for second means both horses are second, the next horse is fourth, and the prize money for second and third is pooled and divided equally between the two.

Three or more horses together

Triple dead heats are rare but possible. The principle is the same: all three horses share the placing, the prize money for the three positions they occupy is pooled and split three ways, and the next horse takes the placing after them. A four-way dead heat would follow the same arithmetic. These are once-in-a-generation events at most, and when one happens it tends to be written about for years.

Why dead heats are rarer than they were

The better the image, the fewer the dead heats. Every improvement in the camera's resolution and recording rate has narrowed the gap a judge can see, which means finishes that once produced a tie are now split by a nose. A judge working from a modern digital image, magnified on a screen, can separate horses that a judge squinting at a developed strip of film in the 1950s could not. Dead heats still happen. They are simply reserved for finishes so close that the best equipment shows nothing between the noses, and that is a smaller set of races than it once was.

That has a quiet consequence for the record books. Historic dead heats and modern ones are not quite equivalent results: an older tie may have been a finish a modern camera would split. Statistics on how often races end in dead heats are therefore not comparable across eras, for much the same reason that hand-timed and electronic race times are not.

How the prize money is split

The arithmetic is straightforward. In a hypothetical race where first pays £10,000 and second pays £4,000, a dead heat for first gives each of the two winners half of £14,000, that is £7,000 each. Neither gets the full first prize; neither drops to second prize. The figures are an illustration, not a quotation of any real race.

A dead heat in the record books: wins, trophies and totals

In the record books, a dead heat counts as a win for both horses. Each is credited with a victory in its record and in its pedigree, and both are listed as winners of the race in the history of that event.

Jockeys and trainers

The same applies to the people involved. Both jockeys are credited with a winner in their seasonal totals, and both trainers with a winner in theirs. For a jockey chasing a championship this can matter: a dead heat in the final weeks of a title race is as good as a win. It also means a single race can produce two "winning jockeys" on the same day, both of whom may well feel they should have had the race to themselves.

Ratings and handicap marks

For handicap purposes both horses have won. The official handicappers treat each as a winner of the race when assessing their marks, with the margin to the next horse home used in the usual way.

What happens to the trophy

The trophy is a practical problem. A racecourse with one cup for one winner must decide what to do. In practice racecourses often provide a second trophy or a replica, or the owners agree an arrangement between themselves. There is no single rule covering it. This page deals with the racing result; how bets on a dead heat are settled is a separate matter covered by betting rules and not discussed here.

When the judge, or the line, was wrong

Mistakes are rare, but they happen. The system has three main weak points: the wrong winning post, a misread image and an error in recording the result.

Courses with more than one winning post

Some British courses, particularly jumps courses where the chase and hurdle tracks finish at different points, have more than one winning post. The judge, the camera and the riders must all be working to the correct one for that race. There have been documented occasions in British racing when riders misjudged which post applied and eased off too early, or kept riding past the line they should have stopped at. Courses mark the correct post clearly and riders are expected to know the layout, but on an unfamiliar track in poor visibility the mistake has been made.

Misread images and corrected results

A judge can misread a close photograph, place the line at the wrong point on a nose obscured by mud or weather, or confuse two horses with similar colours. Silks help, but horses wearing similar colours in a crowded finish can be hard to tell apart on a monochrome or low-light image. When the error is caught, results have been corrected after the race, sometimes after the day's racing had ended.

The power to amend

The Rules of Racing give the BHA a mechanism for correcting a judge's error, even after the result has been declared. It is used sparingly, because the integrity of the result depends on its being final in almost every case, and a correction after "weighed in" is uncommon enough to make news. The arrangements have been refined over the years, and the current wording sits in the Rules of Racing rather than in custom.

Before the camera: placings called by eye

Before 1947, every British result was called by the judge's eye alone. The judge sat in the box on the line and watched. When two horses crossed together, the judge made a call, and the call stood.

The angle problem

The judge sat on the stands side, so the far-side horse in a close finish was always at a disadvantage in the judge's view. A horse on the far rail, a few feet behind a horse on the near side in perspective, could appear to have finished second when it had actually won. Experienced judges knew this and tried to correct for it, but they could not do it reliably, and disputed results were part of racing for two centuries.

Dead heats called by eye

Judges also declared dead heats more often than they do now. Without a camera to separate horses, a close finish that the judge could not split was simply called a dead heat. Some of those dead heats would have been separated by a photograph.

The deciding heat

Before the modern rule of sharing the placing, a dead heat for a big race could be settled by a run-off between the tied horses. The 1828 Derby, a dead heat between Cadland and The Colonel, was decided by a second race over the same course later that day, which Cadland won. By the time of the 1884 Derby, when St Gatien and Harvester could not be separated, the owners agreed to divide the stakes and no run-off took place. The history of the race itself is in our guide to the Epsom Derby.

Year	Event	Significance
1828	Derby dead heat between Cadland and The Colonel	Settled by a run-off later the same day
1884	Derby dead heat between St Gatien and Harvester	Stakes divided, no run-off
1947	Photo-finish camera first used in Britain, at Epsom in April	The judge's eye supported by an image
1949	Derby won by Nimbus in a photograph	Usually cited as the first Derby decided by the camera

Timing races from the same line

The same line that the camera watches is where race times are taken. A modern race time is recorded electronically, with the clock started at the start and stopped as the leading horse crosses the line. On the Flat, the start is the opening of the stalls; over jumps, where races begin from a tape, it is the moment the starter releases the field.

Hand timing and electronic timing

Before electronic timing, times were taken by hand, with officials pressing stopwatches as the field started and as the winner crossed the line. Hand timing introduces small errors at both ends: reaction time when the field starts and when the winner finishes, and uncertainty about the exact moment of the start on a course where the timekeeper was a long way from it. Comparing a hand-timed record with an electronic one is therefore unreliable. A hand-timed course record from decades ago cannot be compared directly with a modern electronic one, and a sensible analyst treats them as different kinds of number.

The time returned for a dead heat

A race time belongs to the winner, so a dead heat for first produces one time shared by both horses. Since the judge could not separate them at the line, they cannot be given different finishing times either; the clock and the camera are reading the same moment. Horses further back are not given individual times in the official result at all. Their performances are expressed through the margins, the lengths behind the winner, which the time gap has already been converted into.

Sectional timing

Sectional timing adds detail between the start and the finish. Tracking systems record the time each horse takes to cover each part of the race, often in furlong segments, which shows where a race was won: a horse that quickened in the final two furlongs, or one that set a strong pace and held on. These figures add to the result rather than replacing it; the finish is still decided by the nose at the line. The ground itself shapes those sectionals, and our guide to how the going is declared at British courses explains how.

• 1828Derby dead heat settled by run-off
• 1884Last Derby dead heat
• 1947Photo-finish camera first used in Britain
• 1949First Derby decided by photograph

Years of events described on this page. 1949 is the year usually cited for the first Derby decided by a photograph.

The camera arrives in Britain, and goes digital

The photo-finish camera was first used on a British racecourse at Epsom on 22 April 1947, on the Grand Metropolitan Handicap. It was introduced to support the judge, not replace them: the judge still declared the result, but could now examine an image before doing so. Within a few years it was standard at British courses.

The first Classics decided by photograph

The 1949 season gave the camera its most famous early test. The 2,000 Guineas at Newmarket that spring was the first Classic settled by a photograph, and Nimbus won it in a very close finish; he then took the Derby at Epsom that June in another photograph, the race usually cited as the first Derby decided by the camera. Results that previously would have rested on a judge's eye were now backed by a picture, and the idea that a Classic could be decided by a nose became normal. The Newmarket Classics that opened that season are covered in our guide to the 2,000 and 1,000 Guineas.

From film to digital

Early photo-finish images were recorded on strips of film that had to be developed before the judge could examine them. That took time, and there was always a gap between the finish and the result. The move to digital cameras removed the developing stage entirely. A modern image is available on screen in the judge's box almost immediately after the horses cross the line, and in recent years racecourses have shown the image on the big screen within seconds of the result being declared.

What has not changed

The judge still declares the result. The camera has made the evidence clearer and faster, but the decision remains a person's. That continuity is deliberate. A camera can record when each nose crossed the line; it takes a racing official to say what the image shows and to stand behind the call, which is why the job still exists at every British meeting. Further reading on the sport and the rest of the site's coverage starts at our England sports guides.