I am thinking that it must be referenced from the first waypoint as many people including myself fly to the first waypoint and then start the mission. I just loaded a mission as per the tips from smiller and it looks good and makes sense given the terrain my area.
From Litchi help file:
Thanks for the thread in getting this function to work. I poked around last night and I hadn't noticed the the new icon in the wrench (we call them spanners over here). Loaded up a new mission and it works a treat. Cheers.
Hmmm, that would make sense since the the home point has been recorded prior to take off and the mission would be aware of that when it references the waypoints in relation to any RTH events for example. I guess I'm trying to say that I don't start the mission until I am airborne and near the first waypoint before I start the mission. Intriguing.
I do the same when starting a mission. But if WP1 is not near takeoff location then this distinction matters when programming waypoint altitudes.
Appreciate your comments, but personally I am not able do this when I launch from home as I have to thread it through the trees for take off and landing and then head for the first WP and start the mission. My first and last WP are within 50 metres of my home point which is the RTH in case something goes wrong. I flew with new settings today and no problems. I set the mission height at least 30 mtrs above the highest tree in the forest and looking at the mission before flying gives the relative height at each waypoint which varies according to the terrain and it is pretty close given the known contours of the area where I fly. I think the relative to ground function and batch editing is pretty schmick.
Understood, that's why I assume a clearance of 30 mtrs (which is a bit over the top) above the forest. Before you launch the mission it clearly tells you the elevation at the various WP to make any corrections if necessary. In my case the elevation dropped 12 mtrs over the trip which still left me plenty of wriggle room. If it showed negative I would adjust it before loading it.
