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Re: [vsnet-chat 6020] Naked-eye limits > But, as far as taking scientifically useful data for variable stars goes, > what is the point of these extraordinary cases? The vast majority of > observers who will submit their observations to VSNET or AAVSO will have a > NELM around 7.6 at 50% detection. I dont think it is a good idea to > suggest observers should strive to make estimates at 5% detection just to > go deeper. Although it will not be very meaningful to suggest naked-eye observers to strive for this, it will be meaningful to observers who are working with the largest possible instrument. > In fact, at this low detection > rate, I commonly see a fainter comp star appear brighter than a brighter > comp star! You just cannot make a reliable comparison based on these > "pops" or flashes of view you get. If you feel insufficient statistics, you probably need to increase the watching time to make a better time-average. An instantanenous watch at such faint stars can be misleading. People have been inventing a method (although it is difficult to explain by words) to more meaningfully treat with these low frequency detections. As I showed yesterday, the statitical limiting accuracy at this detection rate is not so poor as expected. Such a method is comparable to an effort by Sebastian to get accurate V estimates with human eyes. Someone would not want to believe an accurate estimate can be made in Sebastian's method, too. But the reality is not. A slight difference between Sebastian's and Hasegawa-san's methods is that the latter apparently needs more mental concentration. Hasegawa-san sometimes expressed an extreme degree of exhaustion. > The error on the estimate is probably > going to be worse than 0.5 mag at these low detection rates. Why corrupt > the database with such poor values? Should we not report observations whose errors may exceed 0.5 mag? There seem to be a comparable or larger scatter at least in some objects. Regards, Taichi Kato
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
