That's the point I was making earlier. Most telescopes have a FOV of at least 15 arc-minutes. You only need to get the guide stars into the field and go from there.
Also, a telescope's pointing can be off in BOTH RA and Dec. Dec has nothing to do with siderial time. -John ============== [snip] - probably more common these > days - use an optical autoguider. > > Jim > > On 1:59 PM, Brooke Clarke wrote: >> Hi Brian: >> >> Why? Do you just want to see the sidereal time on a display or do you >> need a digital output? >> The Spark Fun "serial enabled" displays use what's called a "back >> pack" that has the PIC 16F88 uC and it's used to do serial data to LCD >> parallel data can control lines. I've made some clocks using that chip. >> http://www.prc68.com/I/PIC16F88.shtml >> http://www.prc68.com/I/PRC68COM.shtml#07092006 >> >> A friend is setting up an observatory where the pointing accuracy of >> the telescope mount is specified as " 7 arcseconds or less >> peak-to-peak periodic error before correction". Much better after >> correction. That implies he needs to know what time it is within tens >> of milliseconds. >> http://www.prc68.com/I/StellarTime.shtml#StrMov >> We looked into different ways to get the time into his computer to >> that accuracy and NTP looks like it will fill the bill, so a GPS >> receiver may not be required. >> >> Have Fun, >> >> Brooke Clarke >> http://www.PRC68.com > > > _______________________________________________ > 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.
