boardsurfr said..PhilUK said..
On my laptop I use GPS-Results software which has a filter, the same as the main GPS-Speedsurfing website which gets rid of irregularities. Uncheck the filter box and you can see the difference.
You know that the unfiltered data are 4 knots too high, but you believe that the filtered data are accurate? That's
very optimistic. Filters at the default settings only remove the worst artifacts.
The top speed you show is 7 knots faster than the previous second, and the next second is 5 knots slower. Such acceleration/deceleration does not even happen on a windsurf board. On a foil, the actual speed differences from second to second are typically much lower, and a 5 knot deceleration without a crash is pretty much inconceivable. Basically, the per-point error of the watch is in the range of several knots - about 10-fold higher than what the units approved for the GPS Team Challenge show. With such poor quality data, even 10-second runs will have a typical error somewhere around 1 knot - which is worse than typical single-point max errors for a Motion or similar high-accuracy unit.
Yes, my GPS isnt that accurate, but it cost me 35 GBP secondhand. On the GPS Speedsailing site, you have to use an approved device for records. They allow other devices for fun, as the cost of GPS devices is getting very expensive.
Unfiltered the average 10s is 23.55 average of best 5 max 29.9
4 knots its 23.25 & 26.19
3 knots its 23.14 & 25.66
2 knots its 22.98 & 25.08
1.5 knots its 22.62 & 24.98
1 knots its 19.58 & 24.22
I think it ignores any run with a trackpoint out of tolerance.
The point was just using max speed as a measure is even less accurate, unless you have a high quality device. Even then I've seen some large differences between the GW60 and the new Chrono device.
)
Good job on the ext.
