Hot Spot to continue for rest of Ashes series
Hot Spot will be used for the remainder of the Investec Ashes series despite tests reportedly showing that silicone tape on bats can disguise faint edges. The ICC's general manager of cricket operations, Geoff Allardice, met with the management of both England and Australia in Durham on Wednesday to discuss concerns with the way DRS was operating and the outcome was that no changes would be made for the rest of this series.
Earlier on Wednesday, the ICC had dismissed a report aired on Channel Nine in Australia that it was investigating the possible use of silicone tape on bats by players from both teams during this series. However, Channel Nine reported on Thursday that Hot Spot inventor Warren Brennan had raised "serious concerns" with the ICC that if tape was used on bats, edges could fail to show up on the technology.
There have been a number of occasions during the Ashes when Hot Spot had failed to detect edges that have otherwise shown up on Snicko. Brennan will not comment publicly on the claims, but Curtin University engineer Dr Masood Khan has been conducting research into thermal infrared processing and has said that silicone tape has the capacity to disguise edges on Hot Spot.
"The chemical composition of silicone tape makes it work as an inhibitor for most radiation," Khan said. "Its physical characteristics also make it insensitive to minor physical impacts. Its chemical and physical features ensure an even conduction and dispersion of heat within its structure, meaning thermal changes caused by the impact of a ball as it hits the edge of a bat may remain unnoticed by a thermal infrared camera such as Hot Spot."
However, the ICC has said that after "very constructive" meetings between Allardice and the management of both teams, it was decided that Hot Spot would continue to be used.
"We acknowledge that the DRS has not performed as effectively during the past three Tests as it has in other series," Allardice said. "The purpose of my visit was to meet with the teams to listen to their feedback, and to identify potential improvements to DRS moving forward. It was very encouraging to hear both teams reiterate their support for the use of DRS. Some of the ideas that were suggested during the meetings could improve the system, and will be considered further by the ICC.
"Hot Spot is an advanced technology that helps us to detect edges. It is conclusive - when there is a mark we know the bat has hit the ball. In working with the operator over several years, we know that the majority of edges are detected by Hot Spot, but there are occasions when a fine edge isn't picked up.
"If there is no mark on Hot Spot, the TV umpire can use replays from different angles to see whether the ball has deflected off the bat, and he can listen to the sound from the stump-microphone to determine whether the batsman has edged the ball. Either deflection or sound can be used by the TV umpire to make his final judgment."
While the ICC did not make any mention of silicone tape in its statement, it said it was looking into a number of ways to improve DRS. One which was trialed during the Old Trafford Test involved the TV umpire accessing replays using a multi-channel monitor system with its own dedicated operator and recording device, rather than relying on the existing TV producers to cue up replays.
"The aim was to get more replay angles to the umpire, faster, so he will be able to make more accurate decisions and minimise delays to the game," Allardice said. "The feedback from this trial has been very positive, and we now need to consider how this technology could be most effectively used as part of the DRS system.
"An ongoing area of focus for the ICC is the training of our TV umpires. Several simulation activities have been conducted over the past 12 months and our elite panel training seminar next month will include several activities aimed at delivering more consistent interpretations of the images and sounds provided to the TV umpire."
Michael Clarke and Alastair Cook both reiterated their support for DRS on Wednesday and flatly dismissed suggestions their players could be using silicone tape, although they said there had clearly been issues during this series. Clarke said one such occurrence was when David Warner survived a review for a caught-behind decision at Old Trafford when he attempted a pull shot and Hot Spot showed no edge.
"I asked Davey when he came off the field if he hit that and he said he did," Clarke said. "I don't know the reason why it's not picking it up. I don't know the answer to that question ... I like DRS being there for the stinkers, the big inside edge, the blatant bat pads where you can see it's a big lbw or big caught behind, I like it for that."
Cook said he was keen for Hot Spot to remain part of the DRS, even though problems had shown up during the series.
"It still gives you more chance of getting the right decision and that's why we are using it in the first place," Cook said. "That's what we've found really strange, some clear nicks that haven't shown up on Hot Spot. It has been strange and we just can't quite work out why it's happening.
"But like all these things there are always big evolutions and hopefully the technology can get it right. At the end of the day we're just trying to get more decisions right so the umpires have less impact on the game. And you're talking about decisions but hundreds and five-fors rather than decisions made by the umpire or the third umpire.
One idea believed to have been discussed at Allardice's meetings that does not concern Hot Spot is the possibility of players not losing a review if an lbw appeal shows "umpire's call". As well as problems with Hot Spot, the series has featured a number of very tight lbw decisions and Shane Watson said this week he believed reviews should give the benefit of the doubt to the batsman rather than to the umpire's call.
Brydon Coverdale is an assistant editor at ESPNcricinfo. He tweets here