Polar Alignment #EXOS2 #polaralignment #ExploreStars


scienceandventure@...
 

Hello there,

I wonder if polar alignment can be assisted in some way by the Explore Stars App.

Celestron equatorial mounts have the All-Star Polar Alignment feature. 

I have an Exos 2 Goto PMC-Eight Equatorial Mount. 

Is there any way to make the Azimuth and latitude axes adjustments with the help of the Explore Stars App?

If so, what steps should I perform to do a precise polar alignment with the help of the Explore Stars App?

I use Explore Stars mostly with my iPad, and I also can use Explore Stars in a Microsoft Surface Laptop with Windows 10.

I really appreciate your help. 

Thank You!!!


Jerry Hubbell - Explore Scientific VP Engineering
 

On Sat, Aug 31, 2019 at 06:57 PM, <scienceandventure@...> wrote:
Is there any way to make the Azimuth and latitude axes adjustments with the help of the Explore Stars App?
Wes and I have been discussing this and we have come up with a way to maybe do this. Wes is currently at the Almost Heaven Star Party (AHSP) ahsp.org in Spruce Knob, WV and is planning on testing this procedure. I am sure if he has any more info he will chime in here.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Joe Izen
 

Jerry, Wes,
Thanks for listening and working to created a polar alignment. I understand you had plate-solving, computer driven astrophotographers in mind and eventually I expect to be one. For now, it would be very helpful to have a polar alignment routine as I work myself up the astrophotography technology ladder.

The main reason I purchased my iExos-100 was to have a mount small enough to throw into a suitcase to chase solar eclipses.  As the polar alignment routine, evolves, please consider a usage example where an iExos-100  is set up in day time for use on the Sun. It would be extremely helpful to be able to do some sort of polar alignment during the daytime when the only object visible is the Sun. It's probably safe to assume that most users have a smartphone or table with an electronic compass.  November 11 is just around the corner, and I suspect the community would make great use of a daytime polar alignment for the Mercury transit.

-Joe


Jerry Hubbell - Explore Scientific VP Engineering
 

Hi Joe,

There are several ways to do a daytime polar alignment, I have used a procedure using a compass and a level, and the mounts native angular positioning precision to get a fairly accurate polar alignment good enough for visual use and for doing lunar, solar, and planetary video imaging. Lunar, solar, and planetary imaging does not require the tracking precision that long exposure deep-sky imaging requires so this is sufficient. I think I have posted the procedure on the forum before, I will have to look for it.
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Wes Mcdonald
 

Up here at AHSP.  Well the weather has been poor sadly.  So I cannot report progress on the alignment idea.  Blah.  Probably running for home tomorrow to prep for Dorian.  Testing to follow after that mess clears.

In any event practice the 2 star alignment procedure as that will be part of what the idea includes.  

Wes


--
Wes, Southport NC
PMC-8, ES ED 127, 10" LX200GPS, Astro-Tech 8" Newt, ETX-90
Polemaster, Orion ST-80 and SAG
Electrical Engineer, Retired


Joe Izen
 

I have a suggestion for those trying to polar align an iExos-100 visually using the bore hole in the right ascension axis that I haven't seen on the group. I had more practice than I care to admit after bumping my tripod. 

1) Adjust the tripod legs so the bubble level shows the mount is level.

2) Set the latitude adjustment to set the latitude on the west (east) side of the mount for northern (southern) hemisphere observers. The bore hole has a 2.5 degree field of view, so your latitude adjustment should be dialed in more precisely. 

3) Rotate the RA axis so that the scope is out of the way. Loosen the azimuth knob and sight over the scope to get close.

4) Return to an approximate home position, then rotate the scope 90 degrees on its declination axis to line up the hole in the declination axis with the RA axis bore tunnel. (Embarrassing how many times I forget this key step and stare down a blocked tunnel!)

5) Crouch and spot the polar star alongside the scope with your dominant eye closer to the mount. Your dominant eye is the one you use to look through an eyepiece. With you eyes fixed on the polar star, slid your dominant eye over to sight through the bore tunnel. Chances are, you won't see the pole star unless you are very lucky. However, if your eyes have held their alignment, you will see an image of where the pole star would be if the mount were transparent, superimposed on the wall of the bore tunnel. If your leveling and latitude entry are good enough, you can rotate the azimuth and spot the pole star at the end of the tunnel. You can test if you've succeeded by closing your non-dominant eye.

6) I am rarely lucky. I usually have to adjust both the latitude/altitude and the azimuth.

7) This two-eye method is a skill that one gets better at with practice. It is tricky to do the first time. It does get easier, but the bore tunnel will never be as easy as a proper polar alignment scope. It requires a bit of patience to do the alignment. If frustration gets the better of you, there was an interesting suggestion in another thread to use a gunsight laser stuck into the bore hole.

8) If you aren't driving your mount with a computer, you will want to go through this visual polar alignment, and something like Wes' home-position finding algorithm (in another thread.) There are some ExploreStars gotchas that cause ExploreStars to switch to RA-only tracking.  The drift is a bigger issue for PMC-8 than with traditional mounts with hand paddles that only do RA tracking. Hand paddles like SynScan offer a polar alignment routine that do much better than visual, bore tunnel alignment, and some of the mounts have polar telescopes which add to cost, but work better than the bore tunnel. In principle, a polar alignment routine could be written for ExploreStars by the ES team or a PMC-8 user who had the skills (I don't). A polar alignment is remains high on my feature list-wish.

Last night, after spotting Polaris and offsetting it as best I could by eye, I read my mount's latitude marker at 31 degrees, even though I was observing at 33.0 degrees. I was more than the 1.25 degree half-width of the bore tunnel off.  Jerry, is the offset due to the intrinsic precision of the level? The latitude marker's calibration precision? The bore tunnel alignment? Operator error?

Joe

 


Jerry Hubbell - Explore Scientific VP Engineering
 

On Sun, May 10, 2020 at 12:26 PM, Joe Izen wrote:
Last night, after spotting Polaris and offsetting it as best I could by eye, I read my mount's latitude marker at 31 degrees, even though I was observing at 33.0 degrees. I was more than the 1.25 degree half-width of the bore tunnel off.  Jerry, is the offset due to the intrinsic precision of the level? The latitude marker's calibration precision? The bore tunnel alignment? Operator error?
Hi Joe,

There are errors in all of these items that combine to cause the overall offset, plus others. Unfortunately even though we can add the precision PMC-Eight electronics and all the software available for it to the mount we are still limited by the price point we are trying to sell them at. The cost to us for manufacturing the mount precludes and limits the time and precision for attaching the latitude marker and the level. That along with how well you set the "Home" position of the iEXOS 100 and the Cone Error limit the typical quick setup precision and result in that offset that you need to "SYNC" out of the mount once you slew to your first target.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!