Today's post is a spiral, perhaps not as impressive as Jim Muth's FOTD 06-11-10 but incontestably a spiral. Ready made at http://maxitersfractalfollies.blogspot.com Yet Another Spiral { ; fract502.gif ; blank ; calctime 0:10:07.09 ; created Nov 06, 2010 ; Fractint Version 2004 Patchlevel 10 reset=2004 type=formula formulafile=kerrym.frm formulaname=km_04 center-mag=0.167019/0.535127/24.2564 params=-0.5/-0.5/-0.6354869228186896/-0.3533127842036195/-0.173558763389\ 996/-0.1402325510422071/0.08810693685720389/-0.7196569719534898 initorbit=0.3/-0.6 float=y maxiter=1500 inside=0 decomp=256 periodicity=0 colors=DHVCGUBET9DS8BR7AQ69P57O36N24M13L02K02K13L25M36N47O69P7AQ8CR9DSAE\ TBGUCHVDIWFKXGLYHMZIO_JP`KRaLSbMTcOVePWfQXgRZhS_iTajUbkVclXemYfnZgo_ip`j\ qakrbmscntepufqvgrwhtxiuyjvzjvziuyhsxgrwfqvdoucntblsakr`jq_hpZgoYfnWdmVc\ lUbkT`jS_iRYhQXgPWfNUdMTcLSbKQaJP`IN_HMZGLYEJXDIWCHVBFUAET9DS8BR7AQ58P47\ O36N24M13L02K02K13L25M36N47O69P7AQ8CR9DSAETBGUCHVDIWFKXGLYHMZIO_JP`KRaLS\ bMTcOVePWfQXgRZhS_iTajUbkVclXemYfnZgo_ip`jqakrbmscntepufqvgrwhtxiuyjvzjv\ ziuyhsxgrwfqvdoucntblsakr`jq_hpZgoYfnWdmVclUbkT`jS_iRYhQXgPWfNUdMTcLSbKQ\ aJP`IN_HMZGLYEJXDIWCHVBFUAET9DS8BR7AQ58P47O36N24M13L02K02K13L25M36N47O69\ P7AQ8CR9DSAETBGUCHVDIWFKXGLYHNZIO_JP`KRaLSbMTcOVePWfQYgRZhS_iTajUbkVclXe\ mYfnZho_ip`jqalrbmscntepufqvgswhtxhtxiuyhtxgrwfqveoucntbmsakr`jq_ipZgoYf\ nXdmWclVbkT`iS_hRZgQXfPWeOUdNTcMSbLQaKP`IO_HMZGLYFJXEIW } frm:km_04{; Kerry Mitchell 26aug98 ; tweaked by rjr so user can input julia parameters ; See the end of the formula general_man-2circ for ; Kerry Mitchell's explanation of the "2 circles ; coloring method". ;originally general_jul_test ; "2 general circles" coloring method for Julia sets ; c = Julia parameter, hardcoded originally to (0.65,0.33) ; p1 = x-circle center ; p2 = y-circle center ; real(p3) = x-circle radius ; imag(p3) = y-circle radius ; bailout hardcoded to 10^12 ; use "decomp=256" coloring ; zc=pixel, c=p4, bailout=1e12, iter=1, rmin=1e12 cenx=p1, radx=real(p3), rad2x=radx*radx ceny=p2, rady=imag(p3), rad2y=rady*rady: iter=iter+1, zc=sqr(zc)+c tempx=|zc-cenx|-rad2x tempy=|zc-ceny|-rad2y temp=tempx+flip(tempy), r=|temp| IF (r<rmin) rmin=r, z=temp ENDIF IF ((|zc|>bailout)||(iter==maxit)) iter=-1 ENDIF iter>0 ;SOURCE: 98msg.frm } Roger Alexander