Minimum altitude + photo interval?
Hi. I would've looked this up myself if there was a free trial but now there isn't so I have to ask. I'm looking for a drone automation app that allows me to make a mapping flight of sorts with inspire 2 where the altitude should be about 2-3 meters and snapping a picture straight down every 30-40cm covering a whole are of maybe 20x20 meters. Can drone link do this? Was testing drone harmony first but it won't let me go lower than 5m altitude and did not support that short distances between photos. Thank you.
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7 comments
The 5M height floor is caused by the DJI SDK and I don't think DL can do anything with it.
Other autonomous flight apps have the same limitation.
I have flown missions with a mavic mini at altitudes lower than 5m. I routinely test at less than 3. As regards the original post, I have difficulty understanding why at an altitude of 2-3 metres one would need to shoot every 30-40 cm. Is some sort of telephoto lens involved in the Inspire 2? I don't think any current drones or apps could accurately position at 30-40 cm intervals even if the software allowed you to specify such a small increment. I suppose one could attempt it with dronelink coupled with a business plan allowing inspection missions, but someone more knowledgeable would need to conform this.
less than 5m is certainly possible - 3 meters is about the lowest I have seen, but it could be lower.
I agree with Ken though. An Inspire 2 does not have a GPS accurate enough for 30-40cm - generally, standard GPS is accurate to within 16ft. You could, perhaps, do this with a Phantom 4 Pro RTK.
I don't really know what the use case is but I would suggest creating some sort of tripod or frame on wheels, attaching a regular camera to it, and pushing it backwards and forward - you could probably mark the wheels to show when you had completed a 30cm movement.
Ultimately, it sounds like you are using the wrong tool for this job to me.
Interesting. How many batteries do you have? 20M/30CM = 66, 66x66=4400 frames. Whew. More than I took (times about 10) doing a 20 acre field. Now take that times some huge factor to stitch those... if that is a goal, but you might just want individual frames. IDK
I am not sure of minimum focal length, but I think 2 meters is getting close, especially for this level of detail? Maybe depends on drone.
I also think the minimum move distance is like .6 meters (?) or the drone doesn't know what to do. (I've run into this trying to "stack" photos from the same location. Have to move away a couple of feet and come back.)
Good Luck!!
Thank you so much for your replies, super helpful!
For the 30-40 cm range, I imagine I wouldn't need GPS. All I want is for the drone to travel in X direction in like 0,4 meters per second while grabbing a picture every second. It doesn't need to be perfectly accurate as the software will align all the images afterward. The important thing is that I get good overlap. In the worst-case scenario, I could film the ground in 4k while the drone is flying its pattern, and render out still images from the movie later on, but I want to avoid compression. Grabbing the frames from a video would be an awful waste of the x7 sensor.
Maybe that's not how the drone flight planning apps works, and instead require to fly solely by GPS?
In reply to Ken, yes indeed telephoto. The idea is to capture high res images close to the ground, using photogrammetry processing to create textures and depth maps of the ground. I could do it handheld with a DSLR, 35mm lens, and walking in a zig-zag pattern shooting images manually, or like Barry said manufacturing a tripod with wheels, or even add motors to it to make it autonomous, but I figured using a drone would be an easier solution and I could drink coffee while it's doing its job :)
Currently, I don't have an Inspire but I would buy as many batteries as necessary.
George K Yeah 4000 images is what I would expect, but depending on the FOV I get from the camera and lens, I might as well be able to increase the distance. The important thing is to have at least 50% overlap, preferably more.
And yes it takes a huge amount of processing, RAM and days processing the data, but it works :-)
Hello,
Interesting use case!
For flying that low, you will likely need to use adaptive flight offsets to manage barometer drift.
https://support.dronelink.com/hc/en-us/articles/4416141457171
Also you'll want to use Distance spacing.
https://support.dronelink.com/hc/en-us/articles/4418765878931-Camera-Overlaps-or-Distance-Image-Spacing-for-Maps-and-Facades
Best thing to do is sign up for an account to see if it works for you, and if it doesn't we can refund you the money if you cancel within 30 days of purchase.
Best,
Jacob
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