Hi Dave,
no need to check the algorithms, you are totally right of course. The difference is just some tenths of an arc second. Which is what I originaly wanted to type but somehow I screwed it up.
I've just checked the values again using todays position of SIRIUS. Here is the result:
Position of SIRIUS for February 27th 2012 at 00:00:00.NavPack Result:
GHA 258.5747° = 258° 34.48'
Dec -16.7372° = 16° 44.23' SAlmanach Result:
GHA 258° 34.5'
Dec 16° 44,0' S
So all well to within a quarter of an arcsecond...
Sorry for causing the confusion. Regards,
Timo