EQASCOM for polar aligning - do you use it?

[Bizibilder]

The sequence is this:

Chose your "o'clock" position.  (I'll assume 12 O'clock here).

Centre polaris precisely using the Alt and Azimuth bolts.

Using ONLY the Alt bolts move polaris to the 12 O'clock position.

Then using the controls NOT the bolts move the mount in RA only (ie use the E or W controls only) until the small circle is over Polaris.

Click on Align polar scope - and the mount will warn you then move to the correct position.

Move polaris to the centre of the little circle using the Alt and Azi BOLTS this time.

Job done.

The Save Home position button is so you can select it another time and omit the first two parts.  (ie just click Move polar scope to home and put polaris in the little circle using the bolts.)

Hope this helps.

[Astrosurf]

I forgot all about this! Thanks for bumping it up. It's really useful info.

[Gina]

Can't use the polarscope so I use AstroTortilla as I have good east and south views.  Very easy and pretty quick

[Astrosurf]

All this astro sw is mind-boggling!

[sloz1664]

The sequence is this:

Chose your "o'clock" position.  (I'll assume 12 O'clock here).

Centre polaris precisely using the Alt and Azimuth bolts.

Using ONLY the Alt bolts move polaris to the 12 O'clock position.

Then using the controls NOT the bolts move the mount in RA only (ie use the E or W controls only) until the small circle is over Polaris.

Click on Align polar scope - and the mount will warn you then move to the correct position.

Move polaris to the centre of the little circle using the Alt and Azi BOLTS this time.

Job done.

The Save Home position button is so you can select it another time and omit the first two parts.  (ie just click Move polar scope to home and put polaris in the little circle using the bolts.)

Hope this helps.

Shouldn't that be:-

Choose Home - Wait for mount to finish slewing.

Choose Polaris (shown as a "Right Arrow + Star Symbol) - Wait for mount to finish slewing.

Align Polaris in the circle. 

I actually align Polaris between the centre of the circle & the inner circle circunference ( I think Chris Shillito hints at this in his video).

This gives me pretty good polar alignment, well good enough for 20 min subs.

cheers

Steve

[russellhq]

I think it's all covered in Chris's write-up here:

http://eq-mod.sourceforge.net/docs/PolarScopeAlignment.pdf

1. Set up the mount in the HOME position i.e. counterweight shaft down.

2. Power up and connect to EQMOD.

3. Disable limits (if enabled), UNPARK.

4. Select your Pole Star

5. Click on the Pole Star HA button. To bring up the PolarScope View window

6. Use EQMOD slew controls to move the mount in DEC so the polar scope has a clear

view)

7. You now need to select a “starting position” of either 3, 6, 9 or 12 o'clock using the

dropdown list. These different starting positions are provided so that you can chose

one that doesn’t result in possible mount collsions if your scope is fitted.

8. Now you must move the mount in RA so that the polaris indicator is at the selected

starting position. Lets assume the 6 o’ clock position has been selected. Here’s how

you can accurately move the mount to this position:

First adjust the mounts Alt/Az bolts to get the Pole Star (shown in red) centred in the

reticule.

Now adjust the Altitude bolt until the Pole Star moves downwards to intercept the

inner circle.

Now slew the mount in RA until the Pole Star indicator is superimposed over the

Pole Star

For the 12 o’ clock position the procedure is the identical except that you would

adjust the altitude bolt to move polaris upwards to intercept the inner circel. For the

3 or 9 o’ clock positions adjust the Azimuth bolts to move the star Right or Left until it

intercepts the inner circle.

9. Click on the Set PolarScope Home button to record this position in the

EQMOD parameter file.

10. Click on the Align PolarScope button , which will cause the mount to

slew in RA to correctly position the Pole Star marker.

11. Adjust the mount using the Alt and Az bolts so that the Pole Star is in the little circle.

This completes polar alignment.

12. PARK the mount back to HOME and re-enable limits (if required).

13. Put the OTA, weights etc. onto the mount, UNPARK and carry out goto alignment as

usual.

14. At the end of the session PARK the mount and power down.

Autonm seems to be suggesting that when they get to step 10 and click the button, the position of the pole star marker through the polar scope does not match the position shown on the screen. I.e. screen shows 8 o'clock but the polar scope shows 2 o'clock. I'm not sure why that would be??

Autonm, maybe you can re-try the procedure following the above step by step and see if you get the same results?

[russellhq]

Also, for me, the Alt bolts are the hardest to adjust when the mount is loaded. So I would suggest moving Polaris to the 3 or 6 o'clock position using the Azi bolts to make things easier (if set-up allows without clashing of course).

[autonm]

thanks for the replies all... just waiting for clear skies and then I'll try a mixture of the above and report back.

[russellhq]

With the moon out tonight, I thought I'd give this a go and see how I got on.

I followed the instructions from Chris's PDF but chose the 9 o'clock position.

This worked well and I checked with a drift align facing south. The drift showed I was still a little bit out, so I made a small adjustment to the Azi bolts and ended up spot on.

I then had a play about with the telescope, imaging the moon then returned it to the polar scope home position and then to the polaris position. I took a screen cap of the polar scope to show where Polaris ended up after the drift align adjustment.

You can see that Polaris was moved slight in from the centre of the circle.

Also, here's the PHD graph of 5 mins of DEC drift showing 0.02' (1 second if my math is correct) of polar alignment error.

Very successful test I must say!

[autonm]

With a break in the clouds tonight I managed to set polar alignment.

With 1 exception... after aligned - I pressed HOME POSITION - which should have reset my scope.

However instead of the weight bar being pointing down, it ended with the weights bar pointing up..... ??????

So I manually rotated the RA back to its home position.

However once I started GOTO;s - everything was spot on... so any suggestions on the above would be great.

1. Question I do have though - is with the scope powered up - there is a red light on my Polar scope - does everyone leave this red light turned on whilst aligning? or does it help to turn it off to start with?

Thanks for the help on this thread.

[russellhq]

Did you press the home button in the polar scope window or the park button on the main EQMOD window? If it was on the polar scope window, then the scope would only move to your chosen clock position and not your PARK position.

[autonm]

cant remember

I was following the You Tube video from Chris.... however I'll rewatch it and retry it again.

[autonm]

quick questoin on the PARK-Home Position.

How does EQMOD know the Park-Home position? Is this based on the position of the mount when I first connect it up?

Thanks

[russellhq]

quick questoin on the PARK-Home Position.

How does EQMOD know the Park-Home position? Is this based on the position of the mount when I first connect it up?

Thanks

Yeah, I think that's what it does. I didn't used pay too much attention to this but now, at the end of a session, I always use EQMOD to park the scope and it always puts it back to the position it was in at the beginning of the session. I only do this because it makes the scope easier to pick up and move back inside.

[themos]

Say, which version of PHD are you running to get that Graph window?

[russellhq]

Say, which version of PHD are you running to get that Graph window?

It's from PHD2 beta:

http://www.daddog.com/phd2