An interesting topic for the community, I’d love to hear your answers!
I recently attended a 2 day training course on Multispectral imaging and got onto the topic of survey altitudes. Depending on what I’m after, I’ve been flying as low as 30m and as high as 90m. However the course instructor, a man of many years experience, said that it was largely pointless flying the M3M much below 70m due to the lens parallax and starting to get poor data.
So what are your thoughts? Nonsense? True?
The parallax is only a problem if the stitching is not done properly and the offset between the lenses is not taken into account. At Pix4D, we are correctly taking into account both the different position and orientation of the different lenses, which means that in principle you can fly as low as you want. Several years back we have tested reconstructing a scene in a few metres distance with PIX4Dmapper with a Sequoia and verified with GCPs that it worked correctly in all bands.
1 Like