The Eye don't lie

It's the first ball of the 2003 World Cup clash between India and Australia. Glenn McGrath races in and bowls a near-perfect in-dipper which beats Sachin Tendulkar's defences and thuds onto his pad. The Australians go up in a full-throated appeal. Umpire Steve Bucknor pauses, takes out a small pocket-sized gadget, looks at it, and rules the batsman not out.

Far-fetched? Not really.

Enter Hawk-Eye, the latest technological innovation to hit the game. Hawk-Eye uses six cameras placed around the ground to track the ball's speed, trajectory and deviation. These 3D images are processed by a central computer, which then predicts, within a couple of seconds of the action, the exact point where the ball would have passed the stumps, or hit them. Best of all, this information can be relayed directly to the on-field umpire through a pocket-sized gadget.

Used purely as a TV tool by Channel 4 during their Ashes coverage, Hawk-Eye came up with some revealing results. Out of 20 lbws given when Hawk-Eye was in operation, eight were found to be wrong; this gives the umpires a success rate of a mere 60 per cent.

As with any innovation, questions have been raised about Hawk-Eye:

Is the machine accurate and reliable?
Tests were conducted where thousands of deliveries were bowled by a bowling machine and filmed by Hawk-Eye. Camera feeds were cut about two metres from the stumps - approximately the point where the batsman would normally intercept the ball. Hawk-Eye proved astonishingly accurate in determining the point of impact, with the maximum deviation observed being a mere 5mm.

Will Hawk-Eye further undermine the importance of the on-field umpire?
It won't. If anything, it will enhance his stature, as he will be empowered to take decisions on the field of play itself. Hawk-Eye will enable him to achieve greater accuracy in his decisions.

Will it will slow down the game further?
No. The gadget takes a mere two seconds to hand its verdict to the on-field umpire. That's as much time as it would take the umpire to respond without an aid.

The umpires are in the best position to judge lbws. Can cameras ever be positioned well enough to eliminate the error of parallax?
Hawk-Eye uses stereo imaging to trace the path of the ball at every point. The technology used does not require a camera to be placed right behind the stumps - six cameras placed around the ground ensure greater accuracy than what a single camera, with only one vantage point, can provide. In fact, tests revealed that umpires themselves suffered an error of parallax: balls going over the top of the stumps were often ruled to be hitting, since the umpires viewed the action from a standing position, not from stump-level.

What happens to the benefit of the doubt? Matches might finish in two days.
Early evidence refutes the claim - during the Ashes series, the umpires ruled wrongly against the batsmen eight times out of 20. The marginal decisions might go in favour of the bowler more often, but Hawk-Eye will still ensure consistency.

Can Hawkeye detect the inside edge to the pad?
It can't in its current version. But enough progress has been made to suggest that a future version will have a solution to that problem as well.

New technology is always frowned upon initially and welcomed later once it becomes apparent that instead of making humans redundant, it enables people to do their jobs better. The concept of using television replays and third umpires once seemed sacrilegious, but the game has benefited vastly from them. Hawk-Eye might well become an invaluable tool for umpires over time - though it certainly won't happen overnight. Once it does, McGrath won't bother to ask twice. He'll just glare at Sachin, and walk back to bowl the next ball.