- Joined
- Nov 19, 2017
From more formal point of view - from preparation phase when the skater goes to entry position. Because there are special clause in the rules about jump attempts - which can spend jump slot even if skater does not leave the ice. From more practical point of view - to determine number of rotations and for toe jumps - when picking foot touches the ice. It represents the beginning of takeoff phase - which consists of picking step, prerotation step, leaving the ice step. Degree of rotation is determined by position of foot on the landing in relation to direction of a jump. Direction of a jump is not determined by any foot or body position during takeoff phase - because it has nothing to do with direction of a jump - i.e. in what direction body will fly in air. And only air trajectory matters because in the end meaning of number of rotations count is to determine number of revolutions in air (which can be counted only in relation to body fly trajectory) plus number of rotations on ice in prerotation phase (since prerotation is not judged). Therefore direction of a jump should be determined postfactum - after the jump was landed. Then we can determine two points on ice - point where foot left the ice and point where foot touches the ice on landing - and draw between them a line. That will be air trajectory of a body - i.e. direction of a jump. And angle between this line and direction of the foot in landing moment when it first touches the ice - will show was there UR or not.
This method allows to determine real degree of rotation very clear - despite falls, twizzle entries and exits from/to jump etc. It doesn't depend on ice tracks, snow eruptions, turns on landing and so on - which are very unreliable ways of making calls some times resulting in wrong calls. Because it's very common occurence when skater makes more turns on ice before jump and after jump - then what contributes to actual jump's number of rotations. In other words - when only part of on-ice rotations can be attributed to rotations in the jump itself and other part - to entry transition or turn after landing. And where that border lies can be determined only with proper direction of a jump - i.e. body fly trajectory.
Considering the above - IMO the way some callers likes to make calls by zooming up the camera on foot in slo-mo - is not very right because this method doesn't allow to see the direction of a jump properly. The most reliable way - from top-down or almost top-down view.
