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HEQ5 Pro / Skyscan HC

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#1 Tel

Tel

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Posted 02 April 2009 - 09:10 AM

Hi Folks,

Perhaps you can please help/ confirm ?

In setting up my HEQ5 Pro, one aspect, which appears on the HC's LCD as I complete entering data prior to conducting the alignment procedure itself, reads as follows for today's date, (04-02-09) and at a (mock) input time of 20:00h UT, :-

Polaris : HA 06:10, Clock 02:54

If I change the month to (say) May (i.e. 05-02-09) the reading changes to:-

Polaris: HA 08:08, Clock 01:05

I'm assuming that "Clock" represents the time of the next transit of Polaris, (judging roughly from Stellarium it should be about 03:00h 4-3-09), but HA (?) -- "something angle" perhaps ?

Secondly, but on the same theme,: I don't use DST preferring to stay with UT all year round, (I'm only ~1^ West of the meridian). However, if I suggest to the HC that I will align using DST, the "Polaris" reading then changes for today's date, to:

HA 05:09, Clock 03:25

Whatever the HA represents it clearly shifts by a factor of one as has the DST hour but why the "Clock" should now be at 03:25, I fail to see the connection !


Many thanks for any explanation you can give me on this one !

Best regards,
Tel

#2 groz

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Posted 02 April 2009 - 10:14 AM

if you look into the polar scope on your heq5, you'll see the outer circle, then a little circle within it. The clock number is where you put the 'little circle'. Now put polaris into that one, and, in theory (assuming the polar scope is correctly aligned with the ra axis), you will be correctly polar aligned.

So for your example:-

Polaris: HA 08:08, Clock 01:05

Rotate the mount so the little circle is at the 1:05 position (how we can set it that accurately is still a mystery, but, we can get really close), then adjust the mount so that polaris is in the little circle.

Voila, polar alignment that's usually 'good enough'.

#3 Tel

Tel

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Posted 02 April 2009 - 11:52 AM

Hi Groz,

Many thanks for the explanation. As a result, all now makes perfect sense and checks out brilliantly ! It's therefore basically a quick way of aligning to the NCP, (as best one can, that is), and thus avoids the need to use the RA setting and longitude /date circles !

Once again, very many thanks for your help,
Best regards,
Tel






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