Thanks very much. That certainly explains the difference in times.
I should have thought of that myself.

--- In guide-user@yahoogroups.com, Jan Manek <jan.manek@w...> wrote:
> At 00:46 24.5.2004 +0000, toadatrix wrote:
> >I am trying to understand the reason(s) for the slight
differences
> >in occultation times as calculated by Guide8b and Occult3 (latest
> >version). For example, my latitude is N43 2' 7.8" and my
longitude
> >is W88 25' 5.2" with an elevation of 280m. I am looking at the
> >December 7, 2004 occultation of Jupiter by the Moon. Occult3
lists
> >the time of first contact for my location as being 8:49:56 UTC
while
> >Guide8b shows the time of this event to be 8:49:22, a difference
of
> >34 seconds.
>
> Hi,
>
> (Win)Occult doesn't list contact times, only time for center of
disk together with duration of partial stage. You are comparing
different things.
>
> Jan
>
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> Jan Manek
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