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Project Noise in flat surfaces versus GSD

I have noticed that on my latest capture I few at 90’ (I don’t remember exactly) but I know I was getting an average GSD of 0.3" which was okay for the height and my camera (DJI inspire 1).

However, I noticed that this data set had more noise on the roads and flat surfaces that previous captures done much closer. Also this latest data set was done in Nadir and not oblique.

The reason I ask this questions - If there is a relationship between sensor and height / distance) is because back in January I acquired data with a Parrot Bebop which has a “lesser” sensor and I was getting a lot of noise throughout the project.

In all instances, calibration is good / acceptable.

hey!

there is a relation between the sensor, the focal length, the flight height and the gsd. Check here: https://support.pix4d.com/hc/en-us/articles/202557469

The gsd will affect the accuracy of your projects. For some cases it is better to fly higher and get big gsd, while for other case it is better to fly lower and get small gsd (higher spatial resolution)

From my experience, for flat areas, it is better to fly lower. In this case, you can see more details on your images, and the reconstruction gets better. 
Now, if your road is totally grey and has no features, flying higher could also help.

I would recommend you to make a test. Fly over a road twice at different flight heights and check the reconstruction. 
Please share the results if you make the test :wink:

Best,