Hello,

I have something like 150-200 logfiles.
Many of theese tracks is in the same area.

It took me a year to realise that water hight, tide depth correction was important to make the maps clean. Because now I have many tracks in the same place but the depths can vary ±20cm
This makes the maps ugly. And it is nearly impossible to adjust this depth manually afterwards.

Is there at way to let the program calculate the tide depth. Does the GPS log x,y,z or only x,y ?
If it logs z would it not be possible to automatically adjust tide depth from a avarage z value from all the logging spots in one fishing trip?
Even if the resulution or accuracy from a single spot is not good enougt.
Would not an avarage valu from all thousands of spots in one trip be accurate enough?

If this is possible, only the distans from waterlevel to GPS sensor would be required to be set manually

Regards
David

With WXtide connected to RM this is done automatically. Unfortunately WXtide does not support tidal data from the entire Globe, so you need to check that it supports a tidalstation near you and shows the data correct. I use it myself and it works pretty good.

The GPS from Your unit cannot reproduce a correct respectively sufficient high Position.
The EPE (x/y accuracy) mostly accuracy about 3 m. A height measurement is much less exactly.

The only way (if wxtide is not available) would be dGPS in a cm range of accuracy for height.

Ok thanks

The logfiles are from lakes. so I guess the WXtide you are speaking of is some sort of database for sea. So that will not work for me.

Guess I will have to do it the time consuming way if I want to clean my maps.

Thanks anyway

Here in Norway we have online data from all the major lakes including waterlevel. I use this to correct all sonalogs. If there is no such data available, making a mark at a pier or something similar and adjusting your data accordingly will do the same.

A good way I have found is to create a calibration track using a known good waterlevel. The track needs to encompass as much of the lake as possible so that as many of your subsequent tracks cross it a couple of times. You can then use this to adjust tracks until the coincident points until are equal, thereby adjusting the whole track to the datum waterlevel.
Alternatively decide on one specific track that represents known good data and adjust all the crossing tracks up or down to it, then use those as datum tracks for the rest until you have the whole area adjusted.

T