"gets rid of all the other parts at the bottom and leaves only full bars top to bottom"
does not sound like keyed rainbow to me.
Sounds like primary and secondary bars (like SMPTE bars):
white, yellow, cyan, green, magenta, red, blue, black.
Is this what you had before "getting rid of the parts on the bottom?"
https://en.wikipedia.org/wiki/SMPTE_...Color_Bars.svg