Hi, I have been trying to geotag images using the data flash logs downloaded from the APM, but I have not been able to get the correct locations to be tagged in the pictures. I suspect that I need to change the Log Offsets line? but I do not know the values. Can anyone tell me how this should be done? Thanks!
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+1,
Just adding to #3, the georef tool uses the time the picture was taken at and the time for each point in the log file to match the picture to the coordinates. You have to change the estimated offset time to match the offset time of the GPS time vs the Camera time in order to get a correct geotag. If your camera has GPS you can set the camera clock to the GPS time and this will reduce the error in this process.
Jaime
What I like to do also is to take a picture of my GPS showing the GPS UTC time. Then I know the precise offset by comparing the photographed time of the GPS with the time in the exif of the picture (exif viewers are available free online).
I think you can detect large errors easily, once the geotagging is done there is a KML file generated, you can open that in google earth and when you put your mouse over one of the pictures, you can see if it matches the location. But for small errors, I am not sure how you can detect an error. Maybe some one else has an idea.
Hi,
Starting too to georef my pictures. I have the same question as yours. How did you find out the right Log offsets? Do you know their meaning?
The log offsets shown tell Mission Planner the position of each item in the log file. So the time is the second item, latitude the 6th item and so on.
Currently on the new version of mission planner I had not had to modify these anymore. The default work, this problem was fixed in later versions than the one mentioned above.
thx, it is clear now.
Well, after a little experimenting and looking at the output files and log files, I found the correct log offsets.
This is with logs from Arducopter 3.1 and Mission Planner 1.2.93.6.
Putting them here for reference.
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