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You can use a spectrophotometer like the Xrite i1 pro (the one maukka uses) that can be found second hand arround 250~350€, or the Xrite i1 studio which can be found new for 350~400€ (I bought mine 360€).
With ArgyllCMS (free) to capture the spectral data and display tint and color rendition info, then you can load the spectral data in Osram color calculator (free) to get more details and export TM-30 reports, also calculate color mixing which is quite fun (that’s where I got my estimation of mixing this 2200K with 4000K SOL, you’ll also see with it that mixing with 2700K won’t lower the duv enough to get what I want), and other stuff.
there is also Argyllpro (100€) to use the spectrophotometer directly with an android device, which is certainly more user friendly and faster.