How can I get more accurate GPS coordinates?

[Danessz]

Hi Everyone!

I am new in WebODM, i just shoot pictures with a Mavic Air 2 and do 3D modeling. I noticed that when displaying the map, the GPS coordinates differ from reality. I display the map, click on a point, then insert the resulting GPS coordinates into Google and notice a large discrepancy. My goal would be that, in the case of surveying an area, by marking a point, another person can find it exactly on the spot. So the question is, how can I achieve all this? What type of settings and configuration do I need to be able to evaluate 300-500 images and collect accurate GPS coordinates?
I like to use drones and I wanted to use an open source software to analyze the images taken in this way. On my laptop I use the free version available from GitHub and Docker, however on my PC I purchased the use of the software to support the developers.
If anyone knows the solution to my problem or can recommend another program that might be suitable for me, please don’t keep it to yourself.

Thanks,

Máté

[Saijin_Naib]

Welcome!

Google Maps is not truth data, so do not rely upon it to decide where things are in reality. The offset in Google Maps from real locations is typically on the order of 3-10m in X/Y, and can be far more severe in Z.

If you must be absolutely certain of the reconstructions location, you should be taking high-quality GCPs using a good survey-grade or mapping-grade GPS (1m or better accuracy, so PPK/RTK/Multi-band).

[APOS80]

Emlid RS2 is a really good and affordable gnss receiver, I got one even though I have gear at work.

With NTRIP correction service it gives you around 2cm accuracy.