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Re: [vsnet-chat 6074] Re: Request for AIP4WIN and other CCD photometry software > The result is a list of positions and magnitudes for all the stars > detected on all the frames. No human intervention is required. I understand the process. I presume that most of professional photometrists have their own ways of doing the more-or-less similar process, but the application is usually limited, or the software would assume some extra skills for operation. This is why I requested to popular/commercial software writers. Usually there is no necessity for human intervention to get raw magnitudes, but there is usually necessity for extracting magnitudes of specific variables (either with additional software operation or with script writing) -- this process could be more facilitated with the current advent of the software technology. The other (more important?) thing is that there is undoubtedly prevailing tendency that "the modes of software operation regulate human modalities". [Do humans use software, or software uses human?] When there are many varieties of software that enable different modes of operation, this would not be a serious problem. But in actuality, automatic photometric software is getting more confined to a single-mode operation, which, in my words, stems from an old fashion established decades ago (this mode is a "CCD synthetic aperture" extension of photoelectric photometry). Although this method is proven to be efficient to some special applications (which are also a fashion among professional astronomers in some 20-30 years ago) to precision photometry of low-amplitude, short-period stars, this is not the sole application of CCD photometry, neither this application illustrates the full potentiality of (amateur) activities with CCDs. For example, this method is suitable for low-amplitude objects, such as novalike variables, short-period pulsators and eclipsing binaries. The amateur applications of CCDs are getting more and more restricted to these objects (see recent IBVS issues), while once the object deviates from this category, there are only few applications. Think how different classes of objects (e.g. from the AAVSO targets) have been continuously observed with CCDs. There are only few exceptions; even the most peculiar object V838 Mon was observed so infrequently that amateur CCD observations were not as efficient as visual observations to fully describe the object's behavior, let alone novae (think how many telescope tracked U Sco or CI Aql outbursts during which CCD time-resolved observations of low-amplitude objects were plenty). The same is true for (more fashionable?) dwarf nova observations. Once the object becomes undetectable with certain software, the obsrervation is usually discontinued even if the original images have extractable information. The result is that there is very restricted coverge of a particular phase of the full development of the dwarf nova behavior. Think how many people stopped observing, or even encouraged to stop observing, after EG Cnc once faded from the 1996 outburst, and the star experienced unexpected series of post-outburst rebrightenings once CCD observers turned their eyes to different objects. If the object had been tracked even after the object faded, there must have been full CCD coverage of at least some of rebrightenings. It was as if the main cause of the rebeightenings was from an instability between the encouraging and discouraging forces after the initial fading ;-) [I leave to readers identifications which were encouraging/discouraging forces; just look back the web/e-mail log]. Such a sad cosequence may be avoided, if the coming software enables meaningful photometry (not simple non-detection) of faint objects, and if the discouraging force is removed. Back to other objects, the lack of observations does not mean the less degree of expected scientific return for the objects which are outside the scope of low-amplitude objects. My experience and suggestion are the rather contrary. The regime of low-amplitude, short-period objects has been so well established in the past decades that research on these objects has been generally confined to (of course, there are exceptions) aim at fine analysis, longer baseline observation, or statistics -- all of them are concepts established dacades ago, and what one can do is an incremental refinement requiring progressively more observing time. If the same amount of telescope time were devoted to different classes of objects, there would have been much more scientific return (of course, there is necessity of different science to interpret the data). I have encountered such classes novelties almost every time I turned the telescope to a different class of object, or an object of timely interest (usually a transient object), since the early 1990's, and would like share the coming wonders with more generalized CCD observers. From my experience, I would warn against the current prevailing fashion of too specialized (and not sufficiently novel) application of CCD photometry. Regards, Taichi Kato
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