Discussion: GPS, Winsplits and RouteGadget discrepancy

So I'm trying to create a routegadget reconstruction of the CCOF Challenge Long with the results off the garmin, a scan of my map, and the winsplits.

I know I started my garmin, and moments later punched the start box.

The map shows fine in routegadget (it's just a map), and the gps pulls in fine from the garmin.

When I separate the route by the winsplits, the circle for the very first split is 14 seconds (or so) too far down the trail.

My split for the first control is 3:35, and that appears to be the length of time that routegadget is taking for the first leg, but that is clearly not what I took for the first leg.

It is as if there is a discrepancy between the start time and the first control time such that it is inflated by those 14 seconds.

I don't particularly care about the time, but I would like to fix the splits so that the circles line up more properly. Since it is a matter of adding time, I can't "cut" from the gps route to fix it.

Any ideas?

Is it possible the SI control boxes were not time synchronized? Does this happen only on the one control? Is there a reversal of it later on another control?

It is "not like" GPS to be off on time. However, it is possible for a heavy canopy or other obstructions to give an incorrect location by up to, say, tens of meters.

Ack - I see I have written routegadget when I meant quickroute... more digging...

Ok, so I "fixed" it, but don't know why it didn't change when I was "fixing" it before...

I edited my start time by making it 15 seconds earlier, and suddenly the split circles seem too be lining up properly.

It is as if the winsplit time is used for the splits, but not the start. I did it "normally" again and noticed that quickroute was saying my first split was 3:20, the same 15 seconds that were missing.

All's well.

(And I probably transpose QR and RG because I edit on QR and then export a file to import to RG...)

If you go into WinSplits, you can select Start Time and see what start time was in the control unit when you started. You can also select Real Times.

Looking at my track times, my start time was 8:31:03, but the control unit Start time is shown as 8:30:46 per WinSplits.

[Edit] QuickRoute seems to have the time starting from the track time, but the first split calculated from the WinSplits Real Time, so they are off, as is the total time in [Edit] QuickRoute.

So, all of the controls could have been synced among themselves, so all times are correct, but since it is off from track start time, the first control is too short, as is the overall time.

Ahh - that makes sense. Different clock syncing...

The overall time should still be correct, as I remember this has to do with the SI-software. Probably all the units are synced between each other but they do not match the read-out computer. If I remember correctly the time difference between the finish unit and the read-out computer is added/subtracted from the split to the first control

Yes, the overall times in SI-software is correct, but it doesn't appear that the overall time in QR is correct under this scenario. It is not correct until I change the start time in my tracks to xx seconds earlier.

I don´t know if this may be the case here - but very often (in Sweden) the Start Triangle on the map and the place where the clock starts are not necessarily the same. This has caused minor problems in the past for me...

your gps is rarely going to match the SI boxes, which can shift a few seconds over the course of a few weeks (hence the reason for syncing them before an event). I've been at an event which had 2 start boxes an hour apart (due to one being fixed for daylight savings and one not) and the same problem at the finish, that was a bit of a nightmare to fix!