Dense cloud below the ground surface

[Stefano]

Hi everyone,
more than once I bumped into the following problem: after a good alignment and low marker errors, the dense cloud results inhomogeneous with lots of points below the surface level. The object is a 6 m quadrat covered by snow. I did not use camera references and I masked the background (sky and mountains). Could this be due to the high reflection of snow? Is there a way to remedy the problem?
Thank you very much and have a great day!
Stefano

[Stefano]

I am sorry,
did I give too few details to receive a reply? It is very important...
Thank you,
Stefano

[ManishSahu]

This is due to texture less surface of Snow. Because of that a lot of points which  are matched are incorrect hence you are getting points below ground.
Try running denseCloud with aggressive filtering. This might remove outlier a lot

[Alexey Pasumansky]

Hello Stefano,

Such noise may be a result of both reflections and lack of the texture on the snowy terrain and also of the oblique angle of the camera orientation.

To eliminate noise after the dense cloud is reconstructed you can try to run Classify Ground Points operation, as it also assigns "low points" class to the similar noise points. Even if it wouldn't be able to detect all those points, but at least a major part of them.
Additionally I can suggest to reduce the area of reconstruction from the bottom side.

[Stefano]

Thank you ManishSahu and Alexey!
Just a curiosity, is it possible to at least improve the reflections by adjusting the white balance or contrast in Lightroom/Photoshop?
Stefano