In David's recent post: ------ My soon-to-be son-in-law sent me this: http://homepages.slingshot.co.nz/~alpersj/mandelbrot/ -David W. Jones gnome@??? authenticity, honesty, community http://dancingtreefrog.com ------ I missed the page's instructions at upper left (they disappear) the 1st time I viewed it: "Use the arrow keys to pan, A and Z keys to zoom, S and X keys to change the threshold." The web page is "live" -- Javascript in your browser calculates the fractal essentially instantaneously -- and you can pan and zoom ("A") into it in real time... I discovered that if you hold down the threshold "S" key for long enough, the image does a kind of "inside out" transformation and eventually becomes an M-set with a white "lake." I'm not sure what the threshold feature is doing -- but, it's not a simple color map rotation. - Hal Lane ######################## # hallane@earthlink.net ######################## --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus