I wanted to do a simple seagrass survey at the beach and to collect geoaccurate coordinates of the quadrats. Ideally the coordinates would be to the centimeter grade accuracy because I want to use the field data to validate the drone orthomosiac after.
(I had initially wanted to collected coordinates of points using a GNSS receiver connected to a base station but it ran out of battery so I tried to make do with the DJI 3M and Drtk2.)
I used the DJI 3M connected to the drtk2 base station to collect geo-coordinates of 50x50cm quadrats by taking an image of the quadrat. I tried to position the drone at the centre of the quadrat each time.
When I export the coordinates of images, the points don't seem to have centimeter+ accuracy... for example, points where I knew were at the rocks closer to the coastline where loaded as closer to sand bank. the error margin was wider than 50cm and the error does not seem to be systematic.
Was it a complete waste to have tried collecting centimetre grade accurate points using the 3M connected to the drtk2 base? Is it just not possible to have expected centimeter plus accuracy this way?
Appreciate your help and time.
Thanks.
Of course you would not have cm accuracy. The DRTK should be at least connected over NTRIP for correction OR put above known coordinate. If you neither do that, the accuracy would be as stated on spec, 1.5 - 2 metre.