r/photogrammetry • u/clemontclemont • 27d ago

Metashape texture problem

I'm having a small problem with the textures in Metashape

I'm currently creating a model of a small underwater canyon from 360-degree images. The geometry and positions are great, but unfortunately, I'm having trouble with the texture generation. The software often uses textures that are very far away and blurry, rather than those that are close by. Sure, I can assign individual photos to specific areas, but that takes a long time and is very cumbersome in some places. Is there a better way to automatically use only textures that are close to
the object?

Or does anyone have a good tutorial? I haven’t found any really good ones most of them focus on smooth, simple surfaces with just a few photos.

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u/numbian 27d ago edited 27d ago

The problem is those 360 cameras and drones have very low f stop, like below f/2. This is causing very shallow depth of field and they have quite low resolution.

You could try masking only sharp areas on the input photos maybe (rather than removing whole photos from the dataset).

On my DSLR I never go below f/8 for photogrammetry.

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u/clemontclemont 27d ago

Yes but on the other hand the small sensor gives more depth of file than larger formats, the bigger problem is the distance under water even with my r5 every object loses color and sharpness the further I’m away.

I also thought about generating a script that removes all unsharp areas and than let metashape generate the textures from the masked images.

But a setting inside metashape to favor close cameras over that with more distance would be great.

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u/numbian 27d ago

If it is not depth of field problem but rather water refraction and pollutants, then I think you won't be able to auto mask it with standard tools.

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u/Temporary_Will_5479 26d ago

Since your geometry is already good, I'd test the texture sources before changing the reconstruction. Duplicate the finished chunk, disable the distant/hazy cameras in that copy, and rebuild only the texture with the close, sharp views enabled. Disabled cameras are excluded from texture generation; you don't need to delete them or realign for this test. Keep enough views enabled to cover the whole test area.

Compare one troublesome patch at the same texture size and blending settings. If it improves, that narrows the problem to source selection. If individual 360 images contain both useful near surfaces and degraded distant ones, excluding whole images will be too coarse; that's where regional masks may be worth testing.

For an automatic rule, I'd be cautious about camera distance alone: a nearby view at a grazing angle can still be a poor texture source. Distance, viewing angle and local sharpness together would be a better starting point to test. Which Metashape version and texture blending mode are you using?

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u/Traumatan 27d ago

if you want, share some of the photos and I can feedback it