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Limited Number of Alignment Stars

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#1 Dave Mitsky

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Posted 22 May 2019 - 12:04 AM

After a long hiatus, I took my Celestron NexStar Evolution outside for some casual observing.  The transparency wasn't good enough to do any traveling.  I set up the scope and looked at the alignment stars and things came to a complete halt.

Why is the selection so limited and why do some of the stars that are included seem to be rather odd choices?  There wasn't a single late spring or summer star that I could use due to the trees in my front yard.  There are enough winter stars that I was able to use the scope on a couple of occasions early in the year.

 

Why are Antares, Arcturus, Spica, and Vega missing as alignment stars?  Is there a way to add them or other suitable options?

 

Dave Mitsky


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#2 james7ca

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Posted 22 May 2019 - 12:29 AM

Those stars should be in the list. However, it is possible to change the display so that only stars that are east or west of the meridian will appear on the hand controller. This has confused me on a number of nights when I inadvertently pressed the "wrong" key while doing the alignment. Of hand, I can't remember what key makes this switch, but it must be documented somewhere.

 

In any case, this is the list of stars that should be usable (according to Celestron):


...only stars brighter than or equal to magnitude 2.5 can be used for SkyAlign. Even though there are about 250 named stars in the hand control database, only 82 can be used for alignment and related tasks. Here is the list:

Star Mag. Constellation name
Sirius -1.5 Alpha CMa
Canopus -0.7 Alpha Car
Arcturus 0 Alpha Boo
Vega 0 Alpha Lyr
Capella 0.1 Alpha Aur
Rigel 0.1 Beta Ori
Procyon 0.4 Alpha CMi
Achernar 0.5 Alpha Eri
Betelgeuse 0.5 Alpha Ori
Hadar 0.6 Beta Cen
Altair 0.8 Alpha Aql
Aldebaran 0.9 Alpha Tau
Spica 1 Alpha Vir
Antares 1 Alpha Sco
Pollux 1.1 Beta Gem
Fomalhaut 1.2 Alpha Psc
Acrux 1.3 Alpha Cru
Mimosa 1.3 Beta Cru
Alpha Centauri 1.3 Alpha Cen
Deneb 1.3 Alpha Cyg
Regulus 1.4 Alpha Leo
Adhara 1.5 Epsilon CMa
Bellatrix 1.6 Gamma Ori
Gacrux 1.6 Gamma Cru
Shaula 1.6 Lambda Sco
Alnilam 1.7 Epsilon Ori
El Nath 1.7 Beta Tau
Miaplacidus 1.7 Beta Car
Alnair 1.7 Alpha Gru
Mirfak 1.8 Alpha Per
Wezen 1.8 Delta CMa
Regor 1.8 1 Vel
Dubhe 1.8 Alpha UMa
Alioth 1.8 Epsilon UMa
Menkalinan 1.9 Beta Aur
Alhena 1.9 Gamma Gem
Avior 1.9 Epsilon Car
Alkaid 1.9 Eta UMa
Atria 1.9 Alpha TrA
Sargas 1.9 Theta Sco
Kaus Australis 1.9 Epsilon Sgr
Peacock 1.9 Alpha Pav
Diphda 2 Beta Cet
Hamal 2 Alpha Ari
Polaris 2 Alpha UMi
Mirzam 2 Beta CMa
Castor 2 Alpha Gem
Alphard 2 Alpha Hya
Alpheratz 2.1 Alpha And
Mirach 2.1 Beta And
Algol 2.1 Beta Per
Alnitak 2.1 Zeta Ori
Saiph 2.1 Kappa Ori
Denebola 2.1 Beta Leo
Kochab 2.1 Beta UMi
Menkent 2.1 Theta Cen
Rasalhague 2.1 Alpha Oph
Nunki 2.1 Sigma Sgr
Schedar 2.2 Alpha Cas
Mintaka 2.2 Delta Ori
Suhail 2.2 Lambda Vel
Muhlifain 2.2 Gamma Cen
Alphecca 2.2 Alpha CrB
Eltanin 2.2 Gamma Dra
Sadr 2.2 Gamma Cyg
Caph 2.3 Beta Cas
Almach 2.3 Gamma And
Naos 2.3 Zeta Pup
Scutulum 2.3 Iota Car
Mizar 2.3 Zeta UMa
Dschubba 2.3 Delta Sco
Ankaa 2.4 Alpha Phe
Merak 2.4 Beta UMa
Phad 2.4 Gamma UMa
Sabik 2.4 Eta Oph
Alderamin 2.4 Alpha Cep
Enif 2.4 Epsilon Peg
Scheat 2.4 Beta Peg
Tsih 2.5 Gamma Cas
Menkar 2.5 Alpha Cet
Aludra 2.5 Eta CMa
Markab 2.5 Alpha Peg



#3 Dave Mitsky

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Posted 22 May 2019 - 12:45 AM

Thanks!  What's the origin of that list?

I also have trouble reading the display on the hand controller,  


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#4 Michael_Swanson

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Posted 22 May 2019 - 12:49 AM

After a long hiatus, I took my Celestron NexStar Evolution outside for some casual observing.  The transparency wasn't good enough to do any traveling.  I set up the scope and looked at the alignment stars and things came to a complete halt.

Why is the selection so limited and why do some of the stars that are included seem to rather odd choices?  There wasn't a single late spring or summer star that I could use due to the trees in my front yard.  There are enough winter stars that I was able to use the scope on a couple of occasions early in the year.

 

Why are Antares, Arcturus, Spica, and Vega missing as alignment stars?  Is there a way to add them or other suitable options?

 

Dave Mitsky

Hi Dave,

 

This is almost always caused by an incorrect date, time, time zone, daylight savings and/or location setting.  Check the Setup Time-Site option in the hand control menu.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com



#5 Dave Mitsky

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Posted 22 May 2019 - 01:02 AM

I found the list.  Now I have to figure out how to access it on the hand controller.



#6 PHO

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Posted 22 May 2019 - 01:04 AM

I agree with Dave.  Why are there 82 stars for aligning, most of which are obscure, little known names?  There should be ~40 stars, spread in RA with some north and south, and all well known.  I also have trouble reading the display on the hand controller.  There should be button to make the display momentarily brighter.



#7 Dave Mitsky

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Posted 22 May 2019 - 01:07 AM

Hi Dave,

 

This is almost always caused by an incorrect date, time, time zone, daylight savings and/or location setting.  Check the Setup Time-Site option in the hand control menu.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com

I entered the required data three different times during the two star alignment procedure, powering down and up again after each "failure".   

 

Could I have a defective hand pad?  It looks almost like the characters are being written over other characters.



#8 Michael_Swanson

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Posted 22 May 2019 - 01:34 AM

I entered the required data three different times during the two star alignment procedure, powering down and up again after each "failure".   

 

Could I have a defective hand pad?  It looks almost like the characters are being written over other characters.

A couple of things:

- look for the "Factory Settings" option in the hand control (HC) menu and execute (this will then require you reset the location and time zone settings)

- check to be sure the battery on your Evolution is fully charged

- what versions are being reported in the HC menu?

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


Edited by Michael_Swanson, 22 May 2019 - 01:35 AM.


#9 sg6

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Posted 22 May 2019 - 02:49 AM

Skywatcher and so I assume Celestron have a bit of an odd arrangement for alignment stars. There are a lot, but if I recall there is also a date or month associated with them. At sometime I located a list and recall some "date" association.

 

At a guess (really is a guess) Meade did theirs by bright single star selection, and likely patented or trademarked this and so Celestron had to find an alternative or face legal action.

 

Would have expected that you could pick your own - the list is usually for the auto align where the scope says go center this star.

 

I can always recall one night where a Skywatcher/Celestron asked for a star to be centered, never heard of it. By the time I got information it was in Leo. My question was Why not Denebola or Regulus? Same constellation, same area of sky, bright and single = easy alignment stars. But no it want a smaller dimmer lesser know one, Why?



#10 james7ca

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Posted 22 May 2019 - 03:11 AM

Thanks!  What's the origin of that list?

I also have trouble reading the display on the hand controller,  

The list of alignment stars can be found here (it's the same list I posted earlier):

 

  https://www.celestro...d-for-alignment

 

According to the hand controller section of the Celestron User Manual for the AVX mount the east/west calibration star list can be toggle with the MENU key, as stated below (from page #15):


note: east/West Filtering – In order to ensure the best possible full-sky pointing accuracy, your computerized mount automatically filters and chooses its initial alignment stars so that the first two alignment stars are located on one side of the Meridian and any calibration stars are on the opposite side of the Meridian, as indicated by the “W” or “E” displayed in the upper-right corner of the LCD. East/West filtering can be changed simply by pressing the MENU button at any time during the alignment process.

Thus, if you inadvertently press the MENU key during the second phase of the alignment you will see the "wrong" set of alignment stars and wonder why the obvious stars aren't available for the alignment. This is the problem I mentioned earlier. I don't really know whether this has caused the OP's problem, but it's confused me now and then.

 

Also this, from page #17 of the manual (brightness of the LCD display)


The “Hand Control” menu allows you to customize certain features of the NexStar+ hand control To access this menu, press the Menu button (#7 on the keypad) and use the scroll buttons to select “Hand Control” and press ENTER Use the scroll buttons to select from the following options:

• lights control: Independently adjust the brightness of the number keypad and the LCD.



#11 Michael_Swanson

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Posted 22 May 2019 - 05:57 PM

<snip>

 

According to the hand controller section of the Celestron User Manual for the AVX mount the east/west calibration star list can be toggle with the MENU key, as stated below (from page #15):

 

Thus, if you inadvertently press the MENU key during the second phase of the alignment you will see the "wrong" set of alignment stars and wonder why the obvious stars aren't available for the alignment. This is the problem I mentioned earlier. I don't really know whether this has caused the OP's problem, but it's confused me now and then.

 

<snip>

Definitely a good bit of info for this discussion for others who end up here in the future, but the east/west filtering is only applicable/available on the GEM mounts so not the source of Dave's issues on his alt-az Evolution mount.

 

Best regards,
Mike Swanson
Author of "The NexStar Users Guide II"
Author of "The NexStar Users Guide"
Author of "NexStar Observer List"
https://www.nexstarsite.com


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#12 james7ca

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Posted 30 May 2019 - 07:56 PM

Mike is correct and the information I gave about the alignment stars and the meridian only applies to a German Equatorial type mount (or similar). Since the OP was using an alt-az mount there would be no need for a mode to limit the alignment stars to those that are either east or west of the meridian.

 

That said, did the OP ever resolve this issue?




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