Also look for the settings called 'floor' and 'ceiling' (if you are using UltraFractal). They are at the bottom of the drop-down lists of options that start "sin..asin..etc" These tend to produce blocks of color as they 'cut off' the mathematics (something like rounding off an answer to the nearest whole number). They don't always give something workable,...but sometimes the experiment is worth it! And they available in almost every coloring algorithm UF has, these days.

RosemaryR
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"This...this is magnificent!"
"Oh, yeah. Ooooo. Aaaaah. That's how it starts.
Then, later, there's ...running. And....screaming."