Re: Need advice with new Mach1GTO: Polar Alignment and drifting


Bruce Donzanti
 

You do not have that problem on the iPhone app. The app on the iPhone only stays open for a few seconds and then you have to open it again - every time you open it, it automatically refreshes

Bruce

On Dec 15, 2017, at 9:01 PM, pnagy@sbcglobal.net [ap-gto] <ap-gto@yahoogroups.com> wrote:

That's not what I meant. Does the app continually refresh the screen while the app open? For example, you could start the app, then setup the mount and scope and that could take 30 minutes and by the time you start polar aligning with RAPAS and if you didn't manually refresh the app, then Polaris position on the screen is 30 minutes behind. I did that once when I didn't refresh Android app about 20 minutes after starting the app and polar alignment was off by a mile.

Peter

---In ap-gto@yahoogroups.com, <donza2735@...> wrote :


Yes- the iOS does always refresh when you open the app

Sent from my iPhone

On Dec 15, 2017, at 7:19 PM, pnagy@... [ap-gto] <ap-gto@yahoogroups.com> wrote:


I have both Android and Windows apps and noticed Windows app ALWAYS refresh the screen continuously to keep showing current Polaris position on the screen but Android app NEVER refresh the screen so Polaris position may be far behind than the current Polaris position. So if you never refresh the Android app and adjusted RAPAS according to old Polaris position (never refresh the screen), then you will have a problem.

I wonder if iOS app always refresh the screen like Windows app does?

Peter


---In ap-gto@yahoogroups.com, <christopher.k.erickson@...> wrote :


Something else has occurred to me.

I have now seen two people having roughly the same problem with the RAPAS and apparently both of them are using the iPhone app to determine Polaris position.

Could it be that there is a bug in the current version of the iOS app?

I am an Android user so I don't have access to the iOS app to check it out. I wonder if there are people here with both the iOS app and APCC (or the Android app) who can compare the two programs to see if they are giving the same answers?


-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com


From: Christopher Erickson [mailto:christopher.k.erickson@...]
Sent: Friday, December 15, 2017 12:20 PM
To: 'ap-gto@yahoogroups.com'
Subject: RE: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting

Double-check your saved Lat/Lon/time/TZ info in the hand controller is correct.

And double-check the stars you are calibrating on.


-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com


From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Friday, December 15, 2017 7:59 AM
To: ap-gto@yahoogroups.com
Subject: Re: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting

Ok- I will try this next time out

I did lock the mirror on the C11 with the two clutch knobs but I did not notice any difference.

And as I told George, I am really confused as to why the RAPAS out of the box and after aligning it with the app has my GOTOs way off and most not even in the FOV despite going to a bright star and doing a recalibrate prior to slewing. Polaris is in clear view of the PA opening in the mount (rough PA) before placing the RAPAS in. I double checked the keypad time and coordinate entries and the scope is balanced and leveled. Is that normal?

So I am out of ideas at this point but I'll do the AZ test you recommend and see if that helps..

Thx

On Fri, Dec 15, 2017 at 9:40 AM, chris1011@... [ap-gto] <ap-gto@yahoogroups.com> wrote:



I am unable to get a star near the meridian and just above the celestial equator to not drift for more than 3 mins when performing an AZ adjustment.
I assume that you mean drift in Declination, is that correct? If the star is drifting in declination you may be adjusting the azimuth in the wrong direction each time.

You can also do another easy test of azimuth this way:
First go to a star overhead near the zenith on one side of the meridian (example: star on the east side of the meridian, scope on the west side). Center the star, using the NSEW buttons, exactly on your chip or use a crosshair eyepiece to center and press Recal.
Next, go to a star further east but not too close to the horizon. Ignore any pointing error in RA, but now bring the star to the Dec center line by turning the Azimuth axis. Now send the mount back to the first star overhead and it should be very near the crosshair. You can move it to the crosshair again via the NSEW buttons and do another Recal.
Finally send the mount back again to the star in the east and it should be very close to the Dec center-line (ignore any offset in RA). You can then do a final touch-up of the azimuth to bring the star to the Dec center-line.

This method of setting the azimuth axis results in the same performance as the azimuth adjustment in the classic drift method. You can check the drift at the celestial equator near the meridian. I would expect zero drift using the above method. I have done this adjustment many times and always got excellent results (it is part of my Quick Drift method).

If you still have any drift in 3 minutes, then something else is wrong - perhaps the mirror in your scope is shifting slightly.

Rolando


-----Original Message-----
From: Bruce Donzanti donza2735@... [ap-gto] <ap-gto@yahoogroups.com>
To: ap-gto <ap-gto@yahoogroups.com>
Sent: Fri, Dec 15, 2017 9:15 am
Subject: Re: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting



Hi George

Yes- completely flush- no separation

To recap the scenario......

After balancing and being level, I do a rough PA and then attach the RAPAS and adjust the ALT and AZ to match the app. I then slew to a bright star, center it, and do a re-calibrate. When I slew to any DSO, none are centered and many are out of the FoV completely even though the scope is in the general area. So, I have been assuming that I need to check the accuracy of the RAPAS and perhaps re-align it slightly. This is when I was trying the drift method which I am having trouble doing - meaning, I am unable to get a star near the meridian and just above the celestial equator to not drift for more than 3 mins when performing an AZ adjustment. I then checked the ALT with a star low in the east near the celestial equator and that was no problem as the star did not drift for the 10 mins after a small Alt adjustment. I then went back to check AZ but drifting keeps occurring regardless as to what adjustments I make, even up to the point where I make such dramatic shifts in AZ that Polaris is almost off the scale when I look at it through the RAPAS. This is confirmed when I removed it and looked through the PA scope hole as Polaris was way off center.

I hope this makes sense as I cannot think how else to explain the problem.

Bruce



On Fri, Dec 15, 2017 at 6:42 AM, George george@... [ap-gto] <ap-gto@yahoogroups.com> wrote:

Is the RAPAS flange flush with the mount’s rear plate, or can you see a little separation?

Regards,

George

George Whitney
Astro-Physics, Inc.
Phone: 815-282-1513
Email: george@...

From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com ]
Sent: Thursday, December 14, 2017 10:53 PM
To: ap-gto@yahoogroups.com
Subject: Re: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting


"I adjust it and to the point where Polaris almost goes off of the RAPAS screen."

Dude, that is a problem. :)

From: ap-gto@yahoogroups.com <ap-gto@yahoogroups..com> on behalf of Bruce Donzanti donza2735@... [ap-gto] <ap-gto@yahoogroups.com>
Sent: Thursday, December 14, 2017 8:43 PM
To: ap-gto@yahoogroups.com
Subject: Re: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting


No!! You are not understanding- enough with the dude! I am in the southern sky.
Sent from my iPhone

On Dec 14, 2017, at 8:34 PM, Bill Long bill@... [ap-gto] <ap-gto@yahoogroups.com> wrote:

Polaris? Dude move the scope to the south sky. Do not attempt to do this in the northern pole. The results will be poor.

From: ap-gto@yahoogroups.com <ap-gto@yahoogroups..com> on behalf of Bruce Donzanti donza2735@... [ap-gto] <ap-gto@yahoogroups.com>
Sent: Thursday, December 14, 2017 8:32 PM
To: ap-gto@yahoogroups.com
Subject: Re: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting


well, I am obviously not doing something right

For AZ adjustment, I have a star near the meridian and just above the celestial equator and have it sitting on the crosshairs of the CCD camera software so that it moves E/W on the horizontal lines and N/S on the vertical lines. When the star drifts up (N) I use the AZ knobs to move it right and then re-center to see if the drift is less. At best, I can only get 3 minutes regardless as to how many times I adjust it and to the point where Polaris almost goes off of the RAPAS screen.

So, no idea what I a doing wrong and not even sure what to try next. So, I hope someone can tell me what to try next. I do not see software helping if the star keeps drifting anyway.

Bruce

On Thu, Dec 14, 2017 at 12:38 PM, chris1011@... [ap-gto] <ap-gto@yahoogroups.com> wrote:


horizontal crosshairs are parallel to east-west motion and the vertical crosshairs are parallel to north-south motion- correct?
Yes, that would simplify your task when doing drift alignment.

Always do azimuth drift align for zero Dec motion first.

Rolando


-----Original Message-----
From: Bruce Donzanti donza2735@... [ap-gto] <ap-gto@yahoogroups.com>
To: ap-gto <ap-gto@yahoogroups.com>
Sent: Thu, Dec 14, 2017 11:33 am
Subject: Re: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting

Roland

Got it - Leveling and balance just the usual setup routine

I need to be careful to confirm my N/S/E/W directions (understand up and down means nothing) so that horizontal crosshairs are parallel to east-west motion and the vertical crosshairs are parallel to north-south motion- correct?

Bruce



On Thu, Dec 14, 2017 at 9:12 AM, chris1011@... [ap-gto] <ap-gto@yahoogroups.com> wrote:

Level and balance does not affect drift. need to know direction of drift, RA or Dec. Up/down/left/right has no meaning.

Rolando



-----Original Message-----
From: Bruce Donzanti donza2735@... [ap-gto] <ap-gto@yahoogroups.com>
To: ap-gto <ap-gto@yahoogroups.com>
Sent: Thu, Dec 14, 2017 11:10 am
Subject: Re: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting

yes and well balanced

On Thu, Dec 14, 2017 at 9:03 AM, Dale Ghent daleg@... [ap-gto] <ap-gto@yahoogroups.com> wrote:


Are you certain that your entire mount is level?

On Dec 14, 2017, at 11:31 AM, Bruce Donzanti donza2735@... [ap-gto] <ap-gto@yahoogroups.com> wrote:



Thanks Roland

I tried last night but could never get Capella, near Zenith, to stop drifting upward regardless as to how far I adjusted with the altitude adjustment knob. I'll try again tonight but it is not obvious at this point what I am doing wrong. I was able to first adjust azimuth from drifting.

On Wed, Dec 13, 2017 at 8:35 AM, chris1011@... [ap-gto] <ap-gto@yahoogroups.com> wrote:


I did an initial rough PA and then used the RAPAS and the app to complete the fine alignment. Using my UltraStar camera at f/5, I did a drift test on Sirius as it was low in the southeastern sky and it remained centered for 5 mins before I noticed any drift. Then I did the same with Menkar just off the meridian and near the celestial equator and it only stayed centered for about 1 and a half minutes.
Start by adjusting the azimuth axis until a star at the meridian near the celestial equator does not drift in Dec. Once that is done, you have half of your alignment finished and won't need to adjust the azimuth any further.

Now all you need to do is adjust the altitude axis. Choose a star near the zenith and raise or lower your altitude axis until that star does not drift in RA. Your mount is now polar aligned and drift is zeroed out over a large portion of the sky.

Now you can adjust the RAPAS alignment so that it puts Polaris at the right point on the scale. From then on you won't have to do the drift align procedure, just use the RAPAs and you should be very close to the pole each time.

Rolando


-----Original Message-----
From: donza2735@... [ap-gto] <ap-gto@yahoogroups.com>
To: ap-gto <ap-gto@yahoogroups.com>
Sent: Wed, Dec 13, 2017 7:58 am
Subject: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting



I just bought a Mach1GTO for my de-forked C11" and am still feeling out how the mount works. I also bought the RAPAS for PA. The scope is balanced and it is leveled in the E/W direction.

I did an initial rough PA and then used the RAPAS and the app to complete the fine alignment. Using my UltraStar camera at f/5, I did a drift test on Sirius as it was low in the southeastern sky and it remained centered for 5 mins before I noticed any drift. Then I did the same with Menkar just off the meridian and near the celestial equator and it only stayed centered for about 1 and a half minutes. I then looked once again on the RAPAS and Polaris seemed spot on compared to the app. So, I am concluding from this that the RAPAS needs to be realigned as AP suggests could be the case.. My question: What is the simplest and best way to do the drift alignment which I have never done?
I am a Mac user and I am aware that AP highly recommends PemPro which is a Windows program vs. doing the drift alignment manually. I also realize that the simplest and best ways may not be the same. I do have an Intel compute stick with Windows 10 if folks think PemPro is the way to go.

Thanks in advance,
Bruce























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