Searched the Forum but didn’t really find an Answer in the last year or so. In the Internet People state everything on Overlapping from 60/60 to 85/90
In order to save Mission time i would like to reduce overlapping for mapping Forests. Right now I’m always flying 80/80 (fron/side). I would like to reduce it to 75/70 or maybe 70/70, or even lower if that would make sense. I only need an Ortho, no 3D Modell or other stuff for those Jobs. Those Jobs also are not so much about Accuracy, only about a fast overview Ortho. Is there any experience on what would be just sufficient overlap for an Ortho of a forest ? If not i will have to try many diffrent Settngs.
I have no experience mapping forests. But keep in mind that 75/67 well run shows each point in 12 images, which should be enough to reconstruct it, so you can start testing setups from there.
Push your frontal overlap as high as you can. 90% or more. This only costs you storage space and a tiny bit of processing time.
Sidelap is difficult to predict and is what costs you survey/air time. I would not start any lower than 75% if you want to be fairly assured you won’t need a refly.
Since the drone stops for every Photo front overlap also costs quite a lot Missiontime. At least with Litchie Waypoints and considering ground elevation profile.
I didn’t find any App for my air2s which would give me elevation profil flights without stop and shoot. Since I’m flying in hilly or mountainius terrain (often between 400 and 800m above sea lvl) quite often i do need the drone to follow the elevtion for saftey and overlapping reasons. Do yo have any App recomondation for no Stop and shoot ?
DJIFlightplanner to produce a flight plan, then Litchi is what I use for mapping flights. Pre-flight it is possible to manually adjust your waypoint heights AGL in Litchi, and still have continuous flying.
Okay, but then you then use Seconds or meters for Litchie to know when to take a photo and not Waypoints right ? Which means you only adjust the AGL on the waypoints and take your Photos between them no matter how the Ground surface between those Waypoints is ? Or am I wrong ? havn’t used DJI Planer yet only Litchie Waypoint Mission tools.
And it seems to me in litchie i can either say take a photo every xy second/meters but it will just be at the height of the last or next waypoint (or maybe between but not following terrain) or you can set the Waypoints (like i do, picture attached) so the drone follows the terrain and takes a Photo at every waypoint but you can’t properly follow the terrain without waypoints can you ?
You input height AGL, front and side overlap in DJIFP, it tells you what speed you need to fly to achieve that front overlap at your time interval, then export .csv file for Litchi.
I look at Google Earth to check ground elevations and adjust waypoints to suit. If there is a ridge in between lower waypoint, I add a waypoint to maintain clearance. Honestly, you don’t need to maintain the height above ground precisely, but it’s best to err on the high side to maintain your overlaps. If you are flying at say 60m AGL, an extra 10m at in some areas wont be noticeable.
The waypoints are at the ends of the flight lines and if you set the end point 100metres higher than the start, the drone rises throughout, not suddenly at the end.
I also generally fly across slopes, rather than up and down them.
