No it won’t rise with the land as it has no downward obstacle avoidance. It will just crash into the ground. But that wouldn’t work how you want even if it had it.
You can keep a slight pressure on the down stick but it’s some thing you would havecto keep an eyevon as too much it will crash into the ground, too little and the gap between the drone and the ground will get greater.
Basically you will just need to practice, getting faster as you get better. It’s probably ( I’m no expert as I don’t do it yet) the very basic of fpv maneuvers i.e. learn to fly fast , straight and level. Then the same with a slight increase or decrease in altitude.
Hmm, it definitely does have downward sensors, as it stops descending at about 1m if you’re manually landing it, and if you try an descend below that it just goes into landing mode. And I’m sure if I move my hand under it, it increases altitude.
Weren’t there some reports of them crashing over water when the reflection confused the downward sensors?
You’re right of course , but they pretty much don’t work as obstacle avoidance more a check to see if there is something solid to land on and then turn the motors off, in fast forward flight even in normal mode, due to the angle of travel of the drone, it’s more forward sensors which would stop you crashing into the ground in this scenario.
The downward sensors are not so much to stop you crashing down but to make sure there is something for it to land on. If you watch a drone with forward obstacle avoidance as it approaches a wall it will stop, it doesn’t matter how long you push forward for it still won’t go forward, unlike the downward sensors keep pulling down it will move down and land.
you could achieve the “fast” by filming slow and then increasing the playback speed in post, as long as you don’t have any moving objects in the footage that will give the game away e.g. Benny Hill walking
Yes, that is what Litchi does. Using the mission, it ensures that your specified altitude is maintained above the ground whilst flying at the speed you set throughout the entire mission. I believe it does by using Google Earth elevation data for your planned mission. It then adds your desired altitude to this to ensure it flies at a fixed height above the ground at all times.
I used this approach when searching for my downed Mini 2, many kms, in a grid formation over sloping fields.
Given that sensors, Litchi, on board barometer and VPS all have tolerances and given that Google Earth height data is probably not sampled very 25 cm or so along and across a surface the likelihood of various factors combining to give a resultant negative height above ground on a fast minimum altitude run is fairly high.
Stevesb’s answer, practice doing it manually and slowly, building up speed as it become more familiar is, IMHO, the sensible way to do it.