I am relly keen to learn more about he ‘science’ behind capturing data for photogrammetry purposes.
I was hoping if people could recommend the best ground sampling distance (GSD) values or value range when capturing drone data/handheld shots? and whether this changes depending on the context of the job.
Not only this but if people could please point me in the right direction with other key pieces of info to look into (GSD values are important for photogrammetry so the equivalent of something with similar importance when capturing data).
It’s hard to recommend “the best gsd values”. In my professional work we aim for 1 pixel = 1mm due to it being survey work for heritage sites in the UK.
Depending on how much detail you require will determine what GSD to aim for. Do some tests at various distances and see what you like - you can use a GSD calculator to see what distances will give you what spec.
The most important thing to remember for photogrammetry is “garbage in, garbage out”; i.e. poor images will lead to poor results, so make sure you know how to expose your images correctly first.
If there’s anything else you want to know just ask!
I really appreciate the honest and clear reply Mister Joshua!
I am really keen to learn and, since this post, I have started to learn more about GSD and other important factors regarding photogrammetry and UAV surveys.
There is still a lot I don’t know, however, I will come to understand in time.
Again, I appreciate you offering your support and I will check out the resources you linked!
