Greg Back to the Solar Radiation, UV and Illuminance.
There are indeed debate regarding direct conversion from Radiation to Illumination (as definitely different entities). Although, extrapolation by a multiplier seems to provide close results (Lux ~ 119.*Rad), per related following references: - US Dept of Commerce / National Bureau of Standards, Solar Radiation and Illumination [1981]: https://www.govinfo.gov/content/pkg/GOVPUB-C13-42a9d8afbf69d850c07ab73935aef0ab/pdf/GOVPUB-C13-42a9d8afbf69d850c07ab73935aef0ab.pdf - Watts to Luxes Ratio for Sollar Radiation by TMY Data for Odessa [2017]: https://www.researchgate.net/publication/318260849_Watts_to_Luxes_Ratio_for_Sollar_Radiation_by_TMY_Data_for_Odessa Per your previous posting and statement: "One might even be convinced that the errors are small relative to the claimed accuracy", as building a table of interpolation points. The above references indeed certify your correct comments... therefore, much credits to you. Xant -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-user/153c9e21-3dfc-4884-98b6-7508e607352a%40googlegroups.com.