They're not obvious visually when they switch from the white emitter, which has "some blue" to the RGB emitters, which have "lots of blue" as you head out in the red/orange spectrum, but your body's "blue sensors" certainly notice.
Unfortunately, our visual system isn't sensitive to the same things our melatonin inhibiting system is sensitive to, so without a spectrometer, you can't really tell what you're seeing.
