NOTE: This image has been changed from the original version. ===================================================== CLASSIC F.O.T.D., October 03, 1997 (Cirrus) Fractal visionaries: Today's unusual fractal is a view of the sky -- nothing solid, just vapor and ice crystals. I was undecided whether to name it "Cirrus" or "Skyscape". I finally decided on "Cirrus", but I could just as easily have given it the other name. There may still be some who doubt that clouds are one of nature's fractals. If so, today's picture should end that doubt. It is a photograph taken from a window of F.C., showing a clear blue sky filled with cirrus streamers. Well, actually it's not a photograph at all, but rather a scene in the Z^2+C Julibrot, sliced in the oblate direction, in the area of the second valley beyond Seahorse valley, the one at -1.368 on the X-axis. One of my fractal projects is to collect fractal representations of all the cloud types. I have had several fine cumulonimbus cloud fractals for quite some time, but today's cirrus fractal is my best cirrus scene to date. That leaves nimbus and stratus fractals yet to be found. And of course I'll also want all the combination clouds, such as cirro-cumulus and alto-cumulus, etc. The formula draws the oblate slices of the Julibrot, which I define as the slices determined by the Mandelbrot Y-axis and the Julia X-axis. The VB in the formula name stands for Variable Bailout. I recently discovered that a very low bailout radius does strange things in some of the odd planes, particularly in that area known as Seahorse Valley, so I altered my formulas to add an easily changed bailout feature. BTW, I wonder what happened to Elephant Valley at the east end of the Mandelbrot set. It has some very good fractal scenes also, and one almost never hears about it. Maybe elephants are simply too clumsy to be associated with fractals. :-) Whatever the case, today's picture of the cirrus clouds has been posted to: http://home.att.net/~Paul.N.Lee/FotD/FotD.html Until tomorrow then, keep looking up. You might see a UFO; you might see a fractal! Jim Muth jamth@mindspring.com jimmuth@aol.com START 19.6 FILE============================================= cirrus { ; 2 minutes at 200mhz, 640x480 reset=1960 type=formula formulafile=cirrus.par formulaname=OblateVB passes=1 center-mag=-1.584890\ 27912513300/+0.01512015871562687/137.8441/1.9206/\ -4.818/3.522 params=0/-1.36818/6/0 float=y maxiter=200000 bailout=100 logmap=yes periodicity=10 colors=000e1Te1Te1Tf1Uf1Uf1Uf1Uf1Vg1Vg1Vg1Vg1Wg1Wh\ 1Wh1Wh1Wh1Xh1Xh1Xi1Xi1Yi1Yi1Yi1Yj1Zj1Zj1Zj1Zk0Yj0Z\ j0_i0_h1`h1ag1bg1bf1ce1de1ed2ec2fc2gb2ha2ha2iZ2jW3\ mT3rQ3wN3zK3zK3zK3zK3zK4zK4zK4zL4zM4zN4zO4zP5zQ5zQ\ 5zP5zO5zN4zN5zN6zO7zO7zO8zO9yOAyOByPCyPCyPDyPEyPFy\ PGyQHyQHyQIxQJxQKxQLxRMxRMxRNxROxRPxRQxSRxSRwSSwST\ wSUwSVwTWwTWwTXwTYwTZwT_wU`vU`vUavUbvUcvUdvVevVevV\ fvVgvVhvViuWjuWjuWkuWluWmuWnuXouXouXpuXquXrtYstZtt\ _tt`utavtbwtcxudxueytfztgzshzsizrjzrkzqlzqmzrnzsoz\ tpzuqzvrzwszxtzyuzzvzzwzzxzzyzzzzzzzzzzzzzzzzzzzzz\ zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz\ zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzlXVlWUlWUlVTmVTmU\ SmUSmTRnTRnSRnSQoRQoRPoQPoQOpPOpPNpONpOMqNMqNLqMLr\ MKrLKrLJrKJsKIsJIsJHsIHtIGtHGtGGuFHtGG`2N`2N`2Na2O\ a2Oa2Oa2Oa2Pa2Pb2Pb2Pb2Pb2Qb2Qc2Qc1Qc1Qc1Rc1Rc1Rd1\ Rd1Sd1Sd1Sd1Sd1Se1Te1Te1T } frm:OblateVB {; Jim Muth z=real(pixel)+flip(real(p1)), c=flip(imag(pixel))+imag(p1), a=sqr(p2): z=sqr(z)+c, |z| <= a } END 19.6 FILE===============================================