Spectra extraction using Cubert X20: Found zig-zag pattern in the high reflectance region. Is it normal?

[JobinFrancisGithub]

I am currently working with the Cubert Ultris X20 hyperspectral camera. Earlier, I encountered issues related to spatial misalignment, but after applying distance correction, the spatial artifacts have significantly reduced.

However, while analyzing the spectral plots, I observed the following:

In the visible region, the spectra appear smooth and consistent.

Beyond 700 nm (in the non-visible/NIR region), the spectra show noticeable dips and bumps. While I do observe an absorption feature around 900 nm—which I assume corresponds to water absorption bands—the overall zig-zag pattern in the high reflectance region is quite unexpected. Most of the literature I’ve referred to shows smooth spectral signatures in this region.

Is this behavior considered normal for the Ultris X20? Could these fluctuations be related to sensor sensitivity, calibration issues, or environmental noise? I’d appreciate any guidance or references on how to interpret or mitigate these spectral irregularities.

[birkholz-cubert]

Hello,
from what you've described, this doesn't seem to be a software-related issue but rather something specific to the camera hardware. So I recommend opening a request through the Service Portal to get further assistance.