Bearing in mind, in the UK, we can only ascend to 120m Max. If the whole desired area cannot be captured in one photo, should you move the drone to the next capture area, or angle the camera from the same position?
I have tried moving the drone, but can’t get images to line up (stitch).
Also what what program (free program) do you recommend to stitch images?
I’d like to capture a large area, of mainly roads and office buildings, to use as a map, any help would be most appreciated
Moving the drone laterally and angling will give you different results and probably require different solutions for stitching.
Staying in one place and taking a bunch of photos by panning left, right, up and down will give you a panorama like Wayne’s above.
I’ve used Microsoft ICE (free if you can find it and are on Windows) for stitching images like this and it does quite a good job.
If you’re wanting to do mapping, then top-down, vertical scanning is probably the way to go and I believe there are different programs for dealing with that sort of thing but I couldn’t tell you off the top of my head what they are.
If you’re having trouble lining up the images have you tried switching the gridlines on? Overlap all the images by a third and microsoft ICE should be able to stitch them together. I normally use ptgui to stictch (not free) but I had some panos that it really struggled with. I decided to give ICE a go before having to add the manual control points. It managed on the problem panos no problem.
For panoramas, use the inbuilt mode but turn on save original images so you can choose to make the pano in photoshop instead.
For orthophotos, fly a regular survey grid then I’d recommend WebODM to make the orthophoto (will also do 3d reconstructions), takes a chunk of computer power and has a bit of a learning curve but produces good results, you can turn off all the 3d stuff and just output an orthophoto if you want to save some time.
WebODM is free (non commerical) if you compile it (dead easy on Linux, a bit harder on Windows) or about £45 for an installer, a relatively easy shortcut is to run it on AWS which on a spot instance will cost you £2-3 per dataset if you dont have a PC to run it on. I own an installer, but have recently switched to having an extra SSD in my PC running linux which I can compile it on a lot easier.
As you can see in my example, you will get some artifacts if there are moving subjects, just to be aware of.