OK, after dropping the amount of coin on the mount, scope, and camera, (my guess in the neighborhood of $40,000 US) a few hundred bucks for a timing solution shouldn't be too bad. Would an external NTP box, perhaps a Soekris Net4501 driven by a Thunderbolt or another GPS receiver with PPS work? My Windows boxes typically track my Soekris NTP server within a few ms, my Macs to about 1 ms, and my FreeBSD boxes to about 30 microseconds.
Ralph On Nov 28, 2010, at 7:50 PM, Brooke Clarke wrote: > Hi Hal: > > FOV is 0.2 min x 0.3 min @0.47arcsec/pixel when using 1x1 binning. The > seeing doesn't often justify 1x1 binning. > > Mount is the Paramount ME. > http://www.bisque.com/help/paramountme/performance_specifications.htm > There's a software package called TPoint where you manually point to known > stars and that data is used to fit a model of the common mount errors and so > correct them. For example if the RA and DEC axis are not at exactly 90 > degrees. After doing many dozens of stars this correction (and the PEC > correction) allow making images without a guide star for say 10 minutes, > something that's impossible on a Meade or Celestron type setup. > > The scope is a Planewave 17": > http://www.planewave.com/index.php?page=1&id0=0&id=1 > > Camera is SBIG STL-11000M > http://www.sbig.com/sbwhtmls/online.htm > > Have Fun, > > Brooke Clarke > http://www.PRC68.com > > > Hal Murray wrote: >> [email protected] said: >> >>> The telescope has around arc second pointing capability so I think he needs >>> a hundredth of a second or slightly better. >>> >> That doesn't sound right. What's the field of view of the telescope? >> >> >> >>> I've found some NMEA software that will set a PC clock, but it expects the >>> data on a COM port. Don't know how it might work with USB data. >>> >> I don't use Windows, but most likely it will magically show up as COMx when >> you plug it in. >> >> >> >>>> It is not clear whether the message is fixed of if it will reply >>>> to queries. >>>> >> Normally, NMEA devices send a clump of "sentences" each second. Usually, you >> can turn off the ones you don't want. >> >> >> >> > <23Apr2010Pauls.jpg>_______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
