Close range photogrammetry


#1

Hello! Is it possible to do close range 3d-reconstruction with opendronemap? Are there any experiences? THX for repy


#2

I have done this a bit. The biggest challenge is getting enough images with the appropriate arrangement – “orbiting” the object at a few different latitudes tends to work pretty well. I have reconstructed a few smaller items this way.


#3

I’ve mapped my apartment quite successfully with ODM before, not sure if that qualifies as close range?

I wonder if we should add a note in the website / project about uses of ODM outside of aerial applications. This has been pointed before. https://github.com/OpenDroneMap/ODM/issues/881


#4

I reconstructed a camera at quite close range. It felt very meta. :slight_smile:


#5

I should say-- there are a few challenges to close photogrammetry that are independent of using OpenDroneMap. One challenge is keeping everything in focus. I recommend using a proper camera, increasing the ISO (within reason) and stopping down the aperture as small as possible to increase the depth of field as much as possible.

Another challenge in post-processing will be removing all the background data from the reconstruction. Also, make sure you keep your lighting bright and consistent – don’t get tempted to put the object on a spinning platform, as the lighting will change too much between images.

But, in tests as compared with other photogrammetry packages, OpenDroneMap does quite well. In WebODM, download of the point cloud can be done from the 3D interface. I don’t think it shows up in the list of downloads yet.


#6

Ok thx! For my purpose i need to have markers to calculate reference points for coordinate system, scan-area or scale definition in close range. OpenDroneMap uses Ground Control Points for aerial photogrammetry, i think. Does it work with e.g CCTag markers or coded markers for application in close range photogrammetry, also? Thx again


#7

Sure! GCPs should work fine with hyper local coordinate systems. You might need to fib a bit and tell it is a know epsg coded coordinate system, but it’s no sin to lie to your photogrammetry software.


#8

Thanks for your detailed information. Helped me out big time! :+1: