Re: No Escape

[Oscar Saa <osaa@ctio.noao.edu>]

. . . and in any case, all observers should always make sure
they are working their equipment well synch to "good time"
What will be the precision required in this case ?
One thing to do with every PC is to monitor/check them
against a "good time source" (GPS or WWV) daily, as part of
the regular start up procedure. (?)
Oscar


aah@nofs.navy.mil wrote:

> Gary,
>   Not all of the installations will be running Linux.
> Those that do and those that are on the internet on a
> semipermanent basis will most likely be running some
> flavor of NTP (I know ours will; right now it is outside
> the firewall and so we have things like NTP turned off).
> So I think the policy should be that you use the best
> possible time source that you can, whether it be a
> manual synch to GPS or WWV or an automated update.
> Perhaps an extra fits header entry that indicates the
> time source would be helpful?  Something like:
>   TIMEBASE= 'Manual GPS'
>   TIMEBASE= 'NTP'
>   TIMEBASE= 'SNTP'
> or somesuch.  I know that ARNE's PC gains about 6 seconds
> per night, about the error that I know the shutter open/close
> times to, so I reset the clock once/day right now while
> the system is outside the firewall.
>   Things like satellite internet are painful; they are
> expensive, require a telephone line for uplink, and usually
> you are not a permanent node.  I think in the future the
> cell-phone-based internet will be the logical choice for
> remote observatories.
> Arne