Does oblique photo help to improve orthophoto (not thinking any 3d models)

As I find this community super helpful, I’d like to ask some more general questions about using oblique photos in generating orthomosaics. I’ve been going through past posts but most of them were saying how oblique photos would help the 3d model construction (which makes perfect sense!).

However, just in orthophoto alone, would oblique photo help to improve the quality or would it actually introduce noises and weird stuff to the process? I’ve heard from Correlator before saying oblique is not too good for 2d orthophoto. I’m wondering what’s ODM’s or just general opinion about this.

Thx in advance!

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5-10 degrees oblique won’t noticeably affect the texturing step that proceeds orthophotos but significantly improves lens calibration which makes everything work better.

More on that here:
https://docs.opendronemap.org/tutorials/#calibrating-the-camera

Or better yet, the actual paper here:
https://onlinelibrary.wiley.com/doi/full/10.1002/esp.3609

So: full obliques only if you need great 3D models, otherwise, just a little angle goes a long way.

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In other words, would this mean for oblique images that have significant larger angles (e.g. 45) may actually worsen the texturing step?

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Not really, the texturing algo will favor nadir shots over non-nadir shots.

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Apologize for not too familiar with texturing algo. But is this “favor nadir shots over others” only apply to odm, or for other softwares it works similarly? (Like my guess for Correlator is that they may not have that favor over things in their algorithm so that they are quite specific of not having oblique images in a mission.)

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Correlator, for all its merits (and this is testing I did a few years ago, so YMMV) comes from a pretty traditional manned aircraft photogrammetry perspective. So their automated image choices are not as sophisticated. But they give the operator a lot of control, so if the imagery meets their spec, they can produce fine results. But off nadir? No: they wouldn’t handle that well.

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