Mike,
Could there be some difference in the color mapping (like forcing logmap or something) that is forced when tdis is in effect?
There is this section of code in calcfrac.c: /* eliminate negative colors & wrap arounds */ if ((coloriter <= 0 || coloriter > maxit) && outside!=FMOD) { if (save_release < 1961) coloriter = 0; else coloriter = 1; } Then further manipulations occur at plot_pixel: I don't see how any of this could cause what you are seeing. Changes in the iteration count are dependent upon when the bailout occurs for outside pixels. So, if the bailout is occurring in the correct place based upon other outside= options, then there must be an error in how totaldist is being calculated. Is new getting set before the bailout is detected or after? When is old getting set? Jonathan