Return to Home Page
Mrac Bos wrote: > Normally I don't follow the discussions on VSnet but your comments about > AIP4Win were forwarded to me . I have also found problems with this > software and therefor don't use it . I prefer DAOPHOT II in the form of > Munipack 2 by Rudolf Novac and his collaborators. When comparing the > output of both these packages I find that the scatter in the comparison > data is consistently higher for AIP4Win by about 40% . Part of the > problem could be that AIW4Win dose not allow one to set a value for the > inner sky annulus, so effectively you could be including some of the > stars light in the sky back ground subtraction. Also, how dose the > software deal with fractions of pixels, hot pixels and stars in the sky > annulus .I know that DAOPHOT dose it very well. Just some thoughts on > the matter. I'll keep using DAOPHOT untill something better comes along > but I can't see that happening in a hurry. I caution anyone complaining about any software package to be sure that they are discussing the latest version, and that they are proficient users of that package. I have seen, by far, more errors caused by incorrect parameter setting and usage than I have by actual algorithm problems. I have seen much good photometry out of almost any software package, most certainly including AIP4WIN. Taichi Kato wrote: > I know how complex DAOPHOT is, and I even >read the "extremely complex" source code of DAOPHOT -- a modern >software engineering would have resulted a much simpler solution...). > The American saying goes: "If it ain't broke, don't fix it." Once you produce a software package that does better and is available in full source code and in public domain, you may have a right to say this, but not before. There is no software package that I know of, including my own, that does not have problems when you are dealing with low signal/noise situations. This is a very tricky regime and I am willing to bet that what works for one case will not work for another. You should avoid low signal/noise regimes until you are experienced. If it is important to use the low signal/noise data, then it is best to have an expert, such as Kato-san, reduce all of the original CCD frames rather than using results from many different observers and reduction procedures. Arne
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
