Any guidance for large area ortho maps?

I have had some good outcomes with small areas of 2Km x 2Km with around 100 photos.

I am trying to get large areas such as 100km x 100km from a high altitude. Here is an example photos:

3840x2160 ~3MB per photo
The photos have exif data (GPS lat/lon/alt meters).
These are captures from a flight simulator so visually slightly different than real earth images, but lat lons match up and these are real areas on earth.

I use WebODM, I upload the normal 100-200 photos flow in a zig zag pattern at a naidir angle (90 degrees down). I have also flow the route twice, second time offset 90 degrees to get a perpendicular routes. I have also tried flying one route nadir, then another at ~80 degrees.

Majority of the times, WebODM will take 1-2 hours and stuck and fail due to multiple reconstructions found. Other times, the maps appear distorted/incorrect GPS positions.

I have verified all the images have EXIF data, and smaller sets at lower altitudes work a lot better. But I am hoping to cover large spans of area.

Any suggestions for a first time ODM user? I have read the ODM uses Point Cloud Maps, and for more high altitude images there are other applications that use stereo imagery and are more commercial oriented products.


Great job on your application! I noticed that you’re going for old school airborne photogrammetry, which is pretty cool.

Just a friendly suggestion though, for your specific case, it might be better to use higher resolution images if available and make sure there’s some ‘altitude’ to the objects you’re imaging. Otherwise, you might just end up with a flat, ‘patterned’ colored images that can’t be triangulated properly. At best, you’ll only be able to stitch the images together.

I’m not entirely sure, but I think someone else might be better equipped to answer this.

What’s your overlap/sidelap on the sets that are giving you trouble?

~70-80% for side and front. The snippet of 5 photos above are a subset and show the overlap. My guess is unlike a real camera, these photos have such small MP size thus not enough detail in the images for processing

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What settings are you using for your Tasks?

Fast Ortho preset

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Hm, can you please try Default next and attach the full console log?

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