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Another basic polar alignment question. Help please!

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#1 mpaul73

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Posted 06 December 2019 - 01:16 PM

I am a little confused as the the polar alignment procedure with my new HEQ5 using the polar scope. I understand that using the app I need to have the pole star match up to the position on the clock. My reticule is NOT the one that has the circle position for Polaris or the big dipper. It's the one showing Octans. Assuming my polar scope is calibrated properly, do I just need to turn the scope on its RA axis until the clock reads 12 top and 6 at the bottom (straight up and down) then adjust the mount to match up the Polaris position on the clock circle according to the app? Am I missing a step? Seems too simple.



#2 wtd1114

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Posted 06 December 2019 - 01:57 PM

Actually, the reticle you have is the preferred one.  It is the newer reticle.  The old one was the the one with the Big Dipper and Cassiopeia and the little circle for Polaris.  Personally, I do not think that one was very accurate for recent years.   Yes, it is as you mentioned.  Given the date and time in your location the app or the hand controller will give you a time position to put Polaris on the reticle clock face.  Notice also there are three concentric circles on the clock face.  This is for the year.  Since we are close to 2020, you can use the center circle.  The outside circle is for year 2012 and the inside one is for 2028.  The trick is to get the clock face so that 12 o'clock  is straight up.  Yep, it is that simple.  So get Polaris positioned on the center circle at the given clock position...

 

Best-

 

Willis



#3 mpaul73

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Posted 06 December 2019 - 02:36 PM

Actually, the reticle you have is the preferred one.  It is the newer reticle.  The old one was the the one with the Big Dipper and Cassiopeia and the little circle for Polaris.  Personally, I do not think that one was very accurate for recent years.   Yes, it is as you mentioned.  Given the date and time in your location the app or the hand controller will give you a time position to put Polaris on the reticle clock face.  Notice also there are three concentric circles on the clock face.  This is for the year.  Since we are close to 2020, you can use the center circle.  The outside circle is for year 2012 and the inside one is for 2028.  The trick is to get the clock face so that 12 o'clock  is straight up.  Yep, it is that simple.  So get Polaris positioned on the center circle at the given clock position...

 

Best-

 

Willis

The reason I asked is that on youtube I saw a video were after positioning the 12 and the 6 up and down, he then turn the RA axis to match the time in H.A. that the app showed?

 

Any tips for getting the 12 straight up and 6 straight down? I guess that is critical when it comes to positioning Polaris in the circle.



#4 zxx

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Posted 06 December 2019 - 02:59 PM

The reason I asked is that on youtube I saw a video were after positioning the 12 and the 6 up and down, he then turn the RA axis to match the time in H.A. that the app showed?

 

Any tips for getting the 12 straight up and 6 straight down? I guess that is critical when it comes to positioning Polaris in the circle.

Be sure the app you're using shows Polaris as viewed through a polar scope, everything is reversed .



#5 kathyastro

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Posted 06 December 2019 - 03:23 PM

The reason I asked is that on youtube I saw a video were after positioning the 12 and the 6 up and down, he then turn the RA axis to match the time in H.A. that the app showed?

 

Any tips for getting the 12 straight up and 6 straight down? I guess that is critical when it comes to positioning Polaris in the circle.

First, be sure that the app is giving you a clock position, not an hour angle.  The video you watched may have been for the latter case.

 

Assuming you have a clock position, positioning the reticle with 12 at the top is the correct way.  Here is how to get a fairly precise vertical:

1. Start with the mount level.  It doesn't need to be level to polar align, but it does need to be level for this step.

2. Position Polaris at the dead centre of the reticle.

3. Use the elevation adjustment to move Polaris out to the circle.  Up or down, it doesn't matter.

4. With Polaris out at the circle, either at the top or bottom, rotate the mount in RA until the 12 or 6 o'clock line, respectively, is over Polaris.

The reticle is now aligned, and you can proceed with the alignment.



#6 mpaul73

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Posted 06 December 2019 - 08:34 PM

First, be sure that the app is giving you a clock position, not an hour angle.  The video you watched may have been for the latter case.

 

Assuming you have a clock position, positioning the reticle with 12 at the top is the correct way.  Here is how to get a fairly precise vertical:

1. Start with the mount level.  It doesn't need to be level to polar align, but it does need to be level for this step.

2. Position Polaris at the dead centre of the reticle.

3. Use the elevation adjustment to move Polaris out to the circle.  Up or down, it doesn't matter.

4. With Polaris out at the circle, either at the top or bottom, rotate the mount in RA until the 12 or 6 o'clock line, respectively, is over Polaris.

The reticle is now aligned, and you can proceed with the alignment.

That makes perfect sense. Is that something I need to do every time I polar align?



#7 kathyastro

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Posted 06 December 2019 - 08:42 PM

That makes perfect sense. Is that something I need to do every time I polar align?

Yes you will, since any RA movement, like tracking, will rotate the reticle.



#8 zxx

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Posted 06 December 2019 - 09:32 PM

That makes perfect sense. Is that something I need to do every time I polar align?

No, not really, this video shows how easy it is with a phone app. 

 

https://www.youtube....h?v=J8xKnX8oKfw


Edited by zxx, 06 December 2019 - 09:52 PM.



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