I am about to do some stockpile mapping in a remote location where i can’t go back and do it again if it doesn’t work out. Any tips on getting accurate image for volumetric stockpile measurement? How critical is good light? I’ll be using both a fixed wing with an S100 and a Phantom 3 Pro. Area is about 100 acres.
Shadows will mess with it so either flown at mid day or cloudy days will net best results. Otherwise you may have to re-fly small sections that were in shade in the morning that are light during the afternoon and vice versa
So overcast won’t be too much of an issue? I’ll be flying this site in the middle of the tropical wet season! Overcast could be quite heavy. I can fly between 11AM-1PM to get the sun at its most vertical.
For dim light the mission should be slowed to compensate… Most mapping programs have this as an option. Also, not sure how you will mix and match the two cameras as accuracy depends on uniformity. Same altitude/overlap/shutter type etc.
Review your pics before you leave the site to help ensure you have what you need.
Shadows shouldn’t be too much of an issue at all. Just make sure you use the elevation toolbox when selecting the boundaries of the stockpile. This will eliminate the shadow issue but you don’t have to worry about that when actually flying. Cloudy shouldn’t be a problem either. Just make sure while you are there that you take a manual sample of the density of the material as DD doesn’t take density into account when calculating volume.
Some tips because you can’t go back, fly the same plan twice but from different directions to increase accuracy and to ensure you got backup images and increase overlap slightly if the area you are covering is not that big.
Good idea on taking two drones. It will be great to hear how they compare. If it works out, our marketing team would likely love to share your story of how the two drones compared.
Better light is good. I’d also recommend using the phantom to take some obliques. It will help likely make a more accurate 3d model.