Topics

Slew Errors #EXOS2 #ExploreStars


Bob
 

1. I polar align the scope with the mount off using sharpcap.  I settle for 'Good' alignment (1 arc min or less) because I don't want to spend the night getting perfection.
2. I then close sharpcap, open settings to find out what serial port is being used (Com Port) after powering up the mount.
3. I go to the ascom control panel, select the exos2 mount (it defaults to G11) and connect using the proper com port.
4. Then I test the connection by trying to slew the mount with the ascom control.
5. Now it is time to hook up APT connecting to the mount and the guide camera.
6. I test the camera and plate solve the result, making sure to hit sync both on the plate solve and in the mount control on APT.
7. I see if the point location for the solution and photo outline match in stellarium.
 
We should be set now to observe.  I ask the mount to slew to M31 (as I am pointing at polaris, it should swing the telescope to the right).
The mount swings the telescope to the left and down.
I direct the mount to park, unpark it once it gets there (the arrows line up on the mount RA/Dec Axis) and plate solve again.
I repeat the sync process and tell the scope to slew to M31.  
It turns left and down again, to the same spot.
 
Then I spend the next few hours restarting the computer, rechecking everything, looking at my new refractor and wishing the damn mount would properly point.  Finally at 3am I tear it all down and put it away.  This has been going on for weeks.  I've considered just putting away the exos2, but I have 700 bucks invested and I want it to perform as expected, ie WORK.
 
Before you ask, the time and location are properly set.
 
Do you have a suggestion short of sending it back?
 
Bob
 
 
 
--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Lloyd Simons
 

Bob,

Can you clarify where you are platesolving? Is at at the North Celestial Pole? If so that can confuse the mount. After polar alignment try slewing to a target (ie M31). If your alignment is decent it should get close. Then platesolve and sync.
--
Lloyd Simons
Mattawan, MI
Telescopes: Astrotech AT72ED II, Orion 8" Dobsonian, Tectron 15" Dobsonian, Celestron Super Polaris C8
Imaging Camera: Canon T3i
Guide Camera: QHY5L-IIM on a 60mm F4 Guidescope
Mounts: iExos-100 PMC-8, Vixen Super Polaris
Mount Control: KODLIX gn41 mini PC, Explorestars on a Lenovo Tab 2 A10-70F Android 6.0
Software: N.I.N.A. for imaging, PHD2 for guiding, Sharpcap for PA, Cartes du Ciel, PixInsight


Tyler Bowman - Explore Scientific Customer Service
 

So one thing i would make sure is the time zone is correct to your current time slot that you are currently in and that means "DAYLIGHT SAVINGS TIME".

Also making sure the latitude is at 44 degrees. 

If you could also make sure that you are pointing at Polaris, some beginners make the mistake of not being on polaris. 

Please don't hesitant to reach out with any more concerns.


Bob
 
Edited

That is interesting, so you suggest rather than plate solving at the park position, I should go to M31 and plate solve there.  But why does the mount swing to the left instead of the right, would the error be that great?

As it is raining now, I'll set it up in the house.  I'll put it in the park position and tell it to slew to M31 and see if it goes the right way.
--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Bob
 

yes, I am pointing at the NCP, I use sharpcap to be sure of that within one min of angle.
--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Tyler Bowman - Explore Scientific Customer Service
 

once i polar align and do a two or three star alignment i sync it to the mount and it should go to the said object that i choose and then i plate solve to make sure that's its where its supposed to be.

Then i use what ever program i use to recenter said object and away i go if that makes sense.


From: MAIN@ESPMC-Eight.groups.io <MAIN@ESPMC-Eight.groups.io> on behalf of Bob via groups.io <drrtownsend@...>
Sent: Thursday, September 3, 2020 2:13 PM
To: MAIN@ESPMC-Eight.groups.io <MAIN@ESPMC-Eight.groups.io>
Subject: Re: [ESPMC-Eight] Slew Errors #EXOS2 #ExploreStars
 

[Edited Message Follows]

That is interesting, so you suggest rather than plate solving at the park position, I should go to M31 and plate solve there.  But why does the mount swing to the left instead of the right, would the error be that great?

As it is raining now, I'll set it up in the house.  I'll put it in the park position and tell it to slew to M31 and see if it goes the right way.
--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Bob
 

Well Tyler here is the problem I have.  Ok, let's say the error is with plate solving at the NCP.  I still slew 'somewhere' and plate solve there, so now the scope should know where it is.  Given that it now knows where it is it should be a simple matter to go where it is told.  Yet it continues to go somewhere else.  I plate solve there, so now the scope again knows where it is pointing, and tell it to go somewhere to a known target, yet it moves in a completely different direction.  Can I reset the mount?  Maybe it starts with bad data and no matter what I tell it to do it is still lost?

--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Tyler Bowman - Explore Scientific Customer Service
 

Lets simplify things and do the basics, manually do a polar alignment or use sharpcap and get a good polar alignment. 
then slew to a object and lets see how far off you are. 

Can i ask what kind programs are you running?

1. Power supply voltage is => 12Vdc
2. Longitude, Latitude, Time, and Time Zone are correct for your location
3. The mount is placed in the Home position according to the index pointers on each axis.
4. The mount is balanced (slight imbalances are okay)
5. The gear mesh is good based on no noticeable excessive motor/drive noise indicative of motor skipping steps.


From: MAIN@ESPMC-Eight.groups.io <MAIN@ESPMC-Eight.groups.io> on behalf of Bob via groups.io <drrtownsend@...>
Sent: Thursday, September 3, 2020 2:28 PM
To: MAIN@ESPMC-Eight.groups.io <MAIN@ESPMC-Eight.groups.io>
Subject: Re: [ESPMC-Eight] Slew Errors #EXOS2 #ExploreStars
 
Well Tyler here is the problem I have.  Ok, let's say the error is with plate solving at the NCP.  I still slew 'somewhere' and plate solve there, so now the scope should know where it is.  Given that it now knows where it is it should be a simple matter to go where it is told.  Yet it continues to go somewhere else.  I plate solve there, so now the scope again knows where it is pointing, and tell it to go somewhere to a known target, yet it moves in a completely different direction.  Can I reset the mount?  Maybe it starts with bad data and no matter what I tell it to do it is still lost?

--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Lloyd Simons
 

Bob, 

If you plate solve and sync at the ncp you can confuse the mount. I think it can break the pointing model. Syncs at the ncp routinely give issues. By omitting this solve and sync you should be fine.
1. Polar align.
2. Turn on mount and connect to software.
3. Slew to Target.
4. Plate solve and sync.
This works well for me.

Looks like we are going to have a couple clear nights here in Michigan for you to try it out. Good luck.


--
Lloyd Simons
Mattawan, MI
Telescopes: Astrotech AT72ED II, Orion 8" Dobsonian, Tectron 15" Dobsonian, Celestron Super Polaris C8
Imaging Camera: Canon T3i
Guide Camera: QHY5L-IIM on a 60mm F4 Guidescope
Mounts: iExos-100 PMC-8, Vixen Super Polaris
Mount Control: KODLIX gn41 mini PC, Explorestars on a Lenovo Tab 2 A10-70F Android 6.0
Software: N.I.N.A. for imaging, PHD2 for guiding, Sharpcap for PA, Cartes du Ciel, PixInsight


Rick Hughes
 

Make sure the mount is at Home position when you power up PMC-8 and don't release clutches. There aren't any encoders so it only knows where it is by counting from Home.
--
Mount: EXPLORE SCIENTIFIC EXOS2-GT EQUATORIAL MOUNT WITH PMC-EIGHT GOTO SYSTEM
Scope: ED115 FPL53 115MM F/5.5 AIR-SPACED TRIPLET ED APO REFRACTOR IN CARBON FIBER


Bob
 
Edited

Of course, and it isn't battery powered, it is line powered to a 110 outlet.

Programs:
Stellarium
Ascom 6.5
APT
Sharpcap
PHD2
--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Bob
 

Yes, right now that is the best suggestion I got and I'll give it a try.  BTW I'm from Gobles and have an office in Kalamazoo.  
--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Bob Trepiccione
 

I would try uninstalling ascom 6.5 and installing v6.4 instead.

I had issues with 6.5 that were resolved when I went to 6.4.

My issues were unrelated to yours, as they were device hub related,  but ya never know...



Sent from my T-Mobile 4G LTE Device


-------- Original message --------
From: Bob <drrtownsend@...>
Date: 9/3/20 5:07 PM (GMT-05:00)
To: MAIN@ESPMC-Eight.groups.io
Subject: Re: [ESPMC-Eight] Slew Errors #EXOS2 #ExploreStars

Of course, and it isn't battery powered, it is line powered to a 110 outlet.
--
Bob T
Mt. Pleasant, MI

EON 110
Meade LX 10
Exos2-PMC


Mike Leemhuis
 

Hi Bob,

I was reading that your scope goes in the wrong direction and I have to ask the obvious question:  Do you have your longitude set correctly?  I am at about the same longitude as you here in Kentucky and I have mine set to 84 degrees WEST longitude.  Is it possible that you have yours set to EAST?  Just want to rule out the easy things first.

Mike

--
Location: Nicholasville, KY
Mount: Explore Scientific Exos-2
Scope: Explore Scientific ED102CF, Orion 60mm guidescope
Camera: QHY163C and QHY5L-ii
Filter: Optolong L-eNhance 2"
Software: ASCOM, PHD2, CDC, Stellarium, Sharpcap Pro, NINA, Deep Sky Stacker, Affinity Photo, Lightroom
Computer:  ASRock X570 Steel Legend, AMD Ryzen 7 3700X 8-Core Processor, 3600Mhz
Extras:  Lots of 3D printed parts I designed for improved usability


Bob
 

Well good news everyone, I think I have it.  There were indeed two problems.

1/ Although it worked fine when I mounted my camera, ATP seems to have changed Long from West to East.  I put it back.  
2/ I avoided doing a plate solve at the NCP.  I did one at Navi about 30 degrees away.  Then I slewed to M31, had to plate solve again and re slewed, Andromeda was in the tracking scope and in the main scope.  Just fined tuned it and was dead on. 

Finally have it working and was able to enjoy an evening of observing thanks to all of you.  Here is the result of 30 stacked and cleaned 60 second exposures...  Now I can fine tune my photoshop skills without struggling with the mount!


--
Bob T
Mt. Pleasant, MI

Orion EON 110//Exos2-PMC8
Meade LX 10" SCT (Pride of the 90's) with LX Drive/Alt-Az Push To
25 x 100 Astronomy Binoculars with Stand
ZWO 110 and 294

APT
Sharpcap
Stellarium


Tyler Bowman - Explore Scientific Customer Service
 

Great news and go enjoy that mount and have fun, 

It's Exciting to hear  a successful story from another customer.