Processing time: perfectly aligned photos vs taken with different yaw/bearing?

My question is mainly about orthomaps, single grid, I can’t prevent unaligned photos to be shot at the extremities of the strips (taken while the drone is turning).

Do they slow the mapping process? Is there any ‘official’ recommendation here, or someone has experimented with that? I wonder if it’s better to manually delete them before processing the set with ODM, or change some ODM settings?

I know it’s recommended to use 2 grids at a different angle for 3D, and even with a single grid you already have 2 different directions - although with a quadricopter you might configure the whole flight with a fixed yaw, if this would make a difference in processing time… Any advice for better performances?

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I use all my ‘taken while turning’ images when mapping, the software has no problem with them, and they may actually help with reconstructed image ( at least around the edges) since they provide a bit more 3D information, having been taken from different bearings to the rest of the images.
Given the relatively small number of them vs the rest of the flight plan, I doubt they have a substantial impact on the time taken to complete a task.

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Thank you. I was looking at flight plans over a slope where a flight path parallel to the isolines seems more appropriate, if that’s also the shorter length of the area of interest, the percentage of unaligned images may be more important… but I can’t find any mention of this being an issue, so I suppose distinct features on the ground is the key, rotation or not…

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Images taken from directions other than the regular flight path are generally beneficial, there is nothing magical about taking images when flying in straight lines, it is really just a method of ensuring you get the coverage and overlap you need.
I almost always attempt to align my flight paths with the contours, so that drone height AGL only needs adjusting during the turns, rather than along the straight runs, although that is sometimes necessary too. Flying up and down a slope will use more energy from your battery due to the extra elevation gain required to cover the area.

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