**5. Conclusions**

The cost of fluorescence sensors is close to ten times that of a hyperspectral or thermal sensor, leading researchers to favour thermal and hyperspectral imaging. However, very few research groups studied the use of a combination of these two sensors in di fferent applications in crop monitoring and sensing. Our results showed that the setup optimisation method for a pushbroom hyperspectral camera, based on maximum signal-to-noise ratio (SNR), tested in wheat can be extrapolated to other crops. However, di fferent set up parameters should be implemented for di fferent crops to allow successful measurement in practice. The optimal set up parameters found in the present study for potatoes and leek are a camera height of 30 cm, a 17◦ camera angle and an exposure time (ET) of 1 ms. In line with camera set up results for wheat, ET was the most important parameter a ffecting SNR, with higher ETs leading to higher SNRs. Measurements in di fferent cropping systems need to be done to determine general applicability of the optimal setup findings. We further concluded that the addition of artificial lights helps counteract the e ffect of cloud cover on reflectance measurements, aiding disease detection. The temperature di fference caused by the additional light appeared to mainly vary with the plant to bare soil ratio. Possible practical applications regarding weed and crop cover assessment with thermal measurements need to be further investigated. Hot spot formation due to artificial light could possibly be used to assess disease stress of certain diseases, due to di fferential heat absorption of healthy versus diseased crops. A comparison between healthy and diseased plants is needed to confirm the hypothesis that disease detection capabilities increase with the addition of artificial light, for both thermal and the hyperspectral sensing.

**Author Contributions:** Conceptualization, S.A., J.P. and A.M.M.; methodology, S.A., A.G., J.P. and A.M.M.; validation, S.A., J.P. and A.M.M.; formal analysis, S.A. and S.N.; investigation, S.A.; resources, A.G.; data curation, S.A.; writing—original draft preparation, S.A.; writing—review and editing, S.A., J.P. and A.M.M.; visualization, S.A.; supervision, J.P. and A.M.M.; project administration, A.M.; funding acquisition, A.M.M. All authors have read and agreed to the published version of the manuscript.

**Funding:** The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Research Foundation - Flanders (FWO) for Odysseus I SiTeMan Project [Nr. G0F9216N].

**Acknowledgments:** Apart from the people listed on this paper, a big thanks to the people at Bottelare experimental farm, UGent mechanical workshop and my colleagues who helped me in the field.

**Conflicts of Interest:** The authors declare no conflict of interest.
