Pitstone windmill

Ok this is my first real attempt at this, so any help or tips appreciated, dataset consisted of 592 photos taken with a mini2, drone settings in a circular facade mission from Dronelink gimbal -5deg, horizontal & vertical overlap 80%

Dronelink settings

Processing Node: node-odm-1 (auto)
Options: auto-boundary: true, mesh-octree-depth: 12, use-3dmesh: true, pc-quality: high, mesh-size: 300000
Average GSD: 1.38 cm
Area: 6,715.58 m²
Reconstructed Points: 3,931,067

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Nice! Enabling --sky-removal as an option to the task should help clean the blades further.

Thanks for sharing.

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Many thanks, I’ll give that a try, as yes the Blades seem to be the major problem

Edit:

I went to do this but couldn’t see it in the option list for the task

see nothing like that here

Sky removal is in the latest native Windows build.

Hi Gordon

Cheers trying to update the desktop the latest build but having problems as described here

https://community.opendronemap.org/t/cant-update-to-build-68/12820/2

Got it on laptop so no idea of what’s going on

Right here’s the latest version, having applied sky removal, below are all the settings

Created on: 23/08/2022, 14:57:21
Processing Node: node-odm-1 (auto)
Options: auto-boundary: true, feature-quality: ultra, mesh-octree-depth: 12, min-num-features: 10000, pc-quality: ultra, rolling-shutter: true, rolling-shutter-readout: 20, sky-removal: true, use-3dmesh: true
Average GSD: 1.43 cm
Area: 6,726.07 m²
Reconstructed Points: 23,536,795

It’s definitely getting there, I’m wondering if i was to take another set of photos as a normal straight line facade of the front of the mill, with 0 deg gimble , , these are the existing cameras

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Your windmill has the same problem as a stack of wood I recently made a 3D model of, and that is the wrong axis is ‘up’. It makes it impossible to view the object of interest from the side, unless it is sideways, with the ground vertical instead of horizontal.

It seems that when all the images are taken from the side, the assumption in the software is that the up axis pokes straight out the front (of the screen), so you can rotate it about that axis, but not about the axis vertically up the screen.

I think that if you fly a lawnmower pattern over the top of the windmill with the camera at -75° and say 85% overlap, then the real up should actually be up in the model, and not sideways, and the rendering of the blades should also improve, assuming they haven’t moved!

cheers Gordon, I’ll give that a go, what type of height would you suggest i fly that at the existing photos go up to 60ft AGL, and no the blades wont have moved as the mill is no longer in use, and just opens for internal tours at the weekend

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I think around 2X the height of the windmill or a bit more, making sure flight speed/ shutter speed doesn’t lead to motion blur.

So if i go to between 120-150 feet, that should do the trick?

Cheers for your help :+1:

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:+1:
.

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Consider taking photos from at least two distances, e.g. inner and outer circles. What I personally do, is take pictures more closely, and from the top as well.

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Cheers, will try that next time I get a chance to get over there

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