ArgyllCMS spectra viewer and converter

a*b* diagram

Spectra processed: 1, wavelength range: 360–740 nm.
CSV file | report: https://pozhvanov.com/spectro?view_id=Ambient_light

#	sRGB	R	G	B	H	S	B(V)	L	X	Y	Z	L*	a*	b*	λmin	λmax	Integral
1	#fcffff	252 255	255 255	255 255	180 0	1 0	100 100	99 100	115.5	124.1	129.8	108.7	-6.4	-17.7	377	493	61.5 K

Use ArgyllCMS to acquire spectra:

#   reflectance spectrum
spotread -v -s -H "file_refl.sp"
#   transmission spectrum
spotread -v -s -H -t "file_trans.sp"
#   emission spectrum
spotread -v -s -H -e "file_emiss.sp"
#   flash emission spectrum
spotread -v -s -H -f "file_flash.sp"
#   ambient light spectrum
spotread -v -s -H -a "file_ambnt.sp"
Do not know how to start?
Try viewing ambient light spectrum or compare cloudy sky with flashlight, macro flash and two different lamps.
Found bugs, have suggestions, etc.? You know where to complain.
Application manual is coming later this year.