EQ6 & HEQ5 with Skyscan (Star Alignment)

EzyStyles (Eric) · #1 19-04-2006, 04:23 PM

Hi,

To all EQ6/HEQ5 with Skyscan owners, what 3 stars do you guys normally align which gives you a good accuracy for the goto? I don't do 3 stars but find that 2 stars is more accurate than 3. Maybe I'm selecting the wrong stars? I presume 3 stars is more accurate than 2 but which 3 stars?

Thanks,

Eric.

OneOfOne (Trevor) · #2 20-04-2006, 08:54 AM

The alignment on my Celestron is probably very similar, but I can only use 3 stars not 2. I don't pick any particular star because sometimes the neighbours trees may be covering some and not others. Usually I try to pick stars that are a fair distance apart. I avoid using a star near the meridian, I did that once and the software got stuck in a loop and I had to turn it off and start again. I think by the time I had finished aligning the other 2 stars, the first one had gone from one side of the meridian to the other...damn it! Try to avoid stars too close to the horizon as the atmosphere will "move them" slightly. I would expect 2 stars would be good enough to find bright, large, easy targets, but 3 would be better if you are looking for something small and obscure. Usually I find the slew to the third star is pretty well spot on. The first is often a handspan out.

allan gould · #3 20-04-2006, 01:50 PM

have a look at this thread.
http://groups.yahoo.com/group/EQ6/message/11938
It explains pretty much all.
I used Spica and Antraes last night for a 2 star alignment and all gotos thereafter were spot on. Prior to this 2 or 3 star alignments were way off and it really was pi#@$ing me off. It all depends on the stars you use. My planet alignments are still way off with version 2.05a but I used ECU with RS232 cord and everything was spot on with all gotos.

matt · #4 20-04-2006, 06:47 PM

Hey Allan

What's ECU?

EzyStyles (Eric) · #5 20-04-2006, 07:06 PM

thanks for the reply. yep just got my answer from the yahoo group. cheers

matt · #6 21-04-2006, 04:25 AM

Hey Ezy

Care to share your info with the rest of us?

EzyStyles (Eric) · #7 21-04-2006, 03:19 PM

hi matt,

the info i got is from:

http://groups.yahoo.com/group/EQ6/message/11938

doing another search, the 3 star alignment which some ppl finds it most accurate in the southern hemisphere are:

1) Achernar
2) Alderbaran
3) Becrux, Mimosa

3 - depends on the time/date . I haven't gave it a shot at those stars yet, but will let you know how accurate the goto is matt. if it is, i'll be staying indoors this winter to do all my imaging in the house

got myself 30 meter cables for the eq6/skyscan with usb repeaters etc.

cheers

allan gould · #8 21-04-2006, 06:56 PM

Sorry, ECU means Earth Centered Universe a planetarium and telescope control program.
Also for what it may be worth I am now controlling my scope with a bluetooth connection through a palm device and an Aircable bluetooth receiver in RS232 port. Works excellently

Rob H · #9 05-05-2007, 12:27 AM

I noticed your comment Allan, about controlling a scope through bluetooth. I've just purchased a AIRcable serial connector myself and I hope to make my Palm TX talk to my EQ6 using Astromist - under suggestions or correspondence would help - e.g. a basic question - does the AIRcable plug into the scope directly or into a serial cable from the base of the Skyscan hand unit - I'm a newbie and still as yet untested in this area!!

ving (David) · #10 05-05-2007, 06:00 PM

i generally try for 2-3 stars that arent too close to eachother.... but my goto is pretty bad sometimes. i am guessing its more my alignment thats out cause i spend little time on it.

Sgtfretsurfer · #11 08-05-2007, 05:55 PM

The guy at the store i bought my setup from told me not to bother with 3 star alignment. According to him, 3 star alignment is only beneficial with 3 stars that exist in an almost perfect equilateral triangle.... dont know how accurate that is but thats what i heard. If its true, good luck finding them!
Matt

ballaratdragons (Ken) · #12 08-05-2007, 09:40 PM

At the moment (coz stars move around as the seasons change) I use Achernar, Betelguese and Acrux. Gives me a sort of good triangle, and seems to give me pretty good accuracy.

Terry B · #13 09-05-2007, 11:57 AM

I don't know about the EQ6 but my skysensor2000 also works on 1, 2 or 3 star alignment. As far as I can remember the difference between 2 and 3 stars is not much in accuracy. What can happen though is that the algorithm that is used to compute the position of the celestial sphere from the 2 stars can occasionally get it completely wrong and the scope will slew in the wrong direction. This is expecially true if you deliberately don't aim the scope at the pole but aim it east or west. I have never done this but it can be done if you want to track satellites and don't want it to deceide to reverse direction as it crosses the meridian. This is eliminated with 3 stars alignment.

As an aside I use acrux, canopus and spica as my 3 star alignment at the moment. It obviously changes as the seasons progress.

matt · #14 09-05-2007, 12:01 PM

Hmmm.

I wonder if anyone has already made a seasonal list of the best stars to use for 2 and 3 star alignments???

Sort of a Winter-Spring-Summer-Autumn line-up (perhaps in chart form) of the best stars to choose from depending on the time of year for the Southern Hemisphere?

Would be a very welcome piece of work if someone could be bothered.

ballaratdragons (Ken) · #15 09-05-2007, 12:07 PM

Quote:

Originally Posted by Terry B

I don't know about the EQ6 but my skysensor2000 also works on 1, 2 or 3 star alignment.

Yep, the EQ6 has 1, 2, and 3 star alignment.

Tamtarn · #16 07-08-2007, 08:42 AM

Quote:

Originally Posted by matt

Hmmm.

I wonder if anyone has already made a seasonal list of the best stars to use for 2 and 3 star alignments???

Sort of a Winter-Spring-Summer-Autumn line-up (perhaps in chart form) of the best stars to choose from depending on the time of year for the Southern Hemisphere?

Would be a very welcome piece of work if someone could be bothered.

We're looking at getting a HEQ5 Pro with Skyscan in the next few weeks and thought this was a good suggestion from an old thread

Has anyone got the time to do it ???

Terry B · #17 07-08-2007, 02:48 PM

Quote:

Originally Posted by Tamtarn

We're looking at getting a HEQ5 Pro with Skyscan in the next few weeks and thought this was a good suggestion from an old thread

Has anyone got the time to do it ???

I agree.
My current ones are acrux, antares and peacock. Good southern winter choices and easy to remember.