Date   

Re: RA Mesh adjustment for 2104 model Mach 1 GTO

W Hilmo
 

I like to use this one:

Take a dime and hold it out arm's length, noticing its diameter.  Now imagine pushing the dime 2.5 miles away.  The diameter of the dime at that distance is one arc second.

-Wade

On 10/14/21 12:20 PM, Howard Hedlund wrote:

>>> Remember we're talking widths of a human hair scale of movement, very small <<<

 

I always liked this analogy: 

  • Hold your hand out at arm’s length and stretch out your fingers as far as you can.
  • Now look at your pinkie fingernail.
  • That fingernail is roughly one degree wide.
  • Now imagine that cut into 3600 equal parts.  That’s the scale of an arc-second.

 

Mag. 7 or Better Skies!

 

Howard Hedlund

Astro-Physics, Inc.

AP Phone: 815-282-1513

Direct Phone:  815-315-7015

www.astro-physics.com

Please include this e-mail with your response.

 

P Consider the environment before printing this e-mail.

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Brian Valente
Sent: Thursday, October 14, 2021 14:04
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

 

>>> It is the standard finder bracket included with the Explore Scientific telescope.

 

can you upload a pic?

 

If it's what I think it is, that can be (and often is) a huge source of movement. Remember we're talking widths of a human hair scale of movement, very small

 

On Thu, Oct 14, 2021 at 11:59 AM nicholas via groups.io <chironik=yahoo.com@groups.io> wrote:

thank you I will check I am certain it is not 6 screws. It is the standard finder bracket included with the Explore Scientific telescope.  I have always thought about this setup being subject to movement but I am frequently manually checking  it to feel for movement which I am not able to discern any.  In any case I will follow-up with the images.


 

--

Brian 

 

 

 

Brian Valente



Dec Arc Tracking in APCC in our Wiki #APCC #Guiding

Howard Hedlund
 

Hi Gang,
One of the great new features in APCC v1.9.x is Dec Arc Tracking.  There was some discussion when v. 1.9.x was released, but there were many other subjects for discussion as well.  In the meantime, I prepared this little tome to hopefully explain it all a bit better.  Please have a look and tell me how I can improve the document.
https://ap-gto.groups.io/g/main/wiki/28325  


Updated Wiki Page: Dec Arc Tracking in APCC #wiki-notice

main@ap-gto.groups.io Notification <noreply@...>
 

The wiki page Dec Arc Tracking in APCC has been updated by Howard Hedlund <howard@...>.

Compare Revisions


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

steve.winston@...
 

@Nicolas, to clarify:  The GA run shown here was done through the main scope, not the guide scope?  So the guide scope connection is not the cause of these DEC jumps...?

Of course, guide camera connection to main scope could still be problematic, dragging cables etc etc.

Do these jumps in DEC repeats across multiple GA runs?


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Howard Hedlund
 

>>> Remember we're talking widths of a human hair scale of movement, very small <<<

 

I always liked this analogy: 

  • Hold your hand out at arm’s length and stretch out your fingers as far as you can.
  • Now look at your pinkie fingernail.
  • That fingernail is roughly one degree wide.
  • Now imagine that cut into 3600 equal parts.  That’s the scale of an arc-second.

 

Mag. 7 or Better Skies!

 

Howard Hedlund

Astro-Physics, Inc.

AP Phone: 815-282-1513

Direct Phone:  815-315-7015

www.astro-physics.com

Please include this e-mail with your response.

 

P Consider the environment before printing this e-mail.

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Brian Valente
Sent: Thursday, October 14, 2021 14:04
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

 

>>> It is the standard finder bracket included with the Explore Scientific telescope.

 

can you upload a pic?

 

If it's what I think it is, that can be (and often is) a huge source of movement. Remember we're talking widths of a human hair scale of movement, very small

 

On Thu, Oct 14, 2021 at 11:59 AM nicholas via groups.io <chironik=yahoo.com@groups.io> wrote:

thank you I will check I am certain it is not 6 screws. It is the standard finder bracket included with the Explore Scientific telescope.  I have always thought about this setup being subject to movement but I am frequently manually checking  it to feel for movement which I am not able to discern any.  In any case I will follow-up with the images.


 

--

Brian 

 

 

 

Brian Valente


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

 

>>> It is the standard finder bracket included with the Explore Scientific telescope.

can you upload a pic?

If it's what I think it is, that can be (and often is) a huge source of movement. Remember we're talking widths of a human hair scale of movement, very small

On Thu, Oct 14, 2021 at 11:59 AM nicholas via groups.io <chironik=yahoo.com@groups.io> wrote:
thank you I will check I am certain it is not 6 screws. It is the standard finder bracket included with the Explore Scientific telescope.  I have always thought about this setup being subject to movement but I am frequently manually checking  it to feel for movement which I am not able to discern any.  In any case I will follow-up with the images.



--
Brian 



Brian Valente


Re: APCC and SGPro Meridian Flip Issues #apcc #ascom_v2_driver #APCC #ASCOM_V2_Driver

ap@CaptivePhotons.com
 
Edited

  • I have the same problem, no matter what combination of settings I use, APCC always reaches its meridian limit a couple of minutes before SGP, causing the SGP session to abort.

 

I had a similar issue in NINA.  In that case both NINA and APCC showed a time to meridian and they did not agree (by 2-3 minutes).

 

In my case the issue was a mount sync issue.  I had NINA set to not sync APCC, and APCC had a polar align but I had done nothing in APPM to sync it (was not using a model either).  So it was tracking nicely but was rotationally off a bit in where it thought it was (and a plate solving center on NINA had the object in view so I was clueless).

 

Allowing NINA to send a sync (which ASCOM or APCC reinterprets as a recal I think) fixed it and all match.  I also am getting into the habit (as it might flush other issues) even if not using a model to go into APPM and do a plate solve and recal first thing after polar align in the evening.

 

Since that, the meridian timing is within a second or few, and flips work flawlessly. 

 

Just a thought.  The meridian screen in APPC shows time of meridian, it should match the transit time of the object (if SGP doesn't show it, you can look up in stellerium or others) .  Unfortunately it stops showing it once it hits the meridian so it is tough to debug after it fails.

Note I'm doing this with limits AT the meridian, I do not know how the display shows if you have other limits beyond for CW up tracking.

 

Linwood

 

 


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

nicholas
 

thank you I will check I am certain it is not 6 screws. It is the standard finder bracket included with the Explore Scientific telescope.  I have always thought about this setup being subject to movement but I am frequently manually checking  it to feel for movement which I am not able to discern any.  In any case I will follow-up with the images.


Re: APCC and SGPro Meridian Flip Issues #apcc #ascom_v2_driver #APCC #ASCOM_V2_Driver

Marcelo Figueroa
 

On Thu, Oct 14, 2021 at 07:23 AM, Tom Zepf wrote:
Hi folks, I seem to be having issues with getting SGPro and APCC setup for successful meridian flips. In all cases, the mount stops tracking before the meridian limit is reached. There seem to be two issues.

I have the same problem, no matter what combination of settings I use, APCC always reaches its meridian limit a couple of minutes before SGP, causing the SGP session to abort.
 
If I use send the limits to SGP it is even worse, because for some reason SGP thinks it reached the meridian a couple of hours before the real event.
 
From my ignorant point of view it would be ideal to be able to set in APCC an offset for after the meridian.
 
And just in case, if I totally disable the meridian limits in APCC and let SGP do everything on its own, it works perfect. But I would like to have some safety in case something goes wrong.
 


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Peter Nagy
 

Nicholas, 

Please show us several good pictures of your guide scope setup including how it's mounted to either your main scope or mount. Does your guide scope bracket have 3 or 6 thumbscrews supporting the guide scope?

Peter 


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

 

Hi Nicholas

I'm a little confused/concerned about these large and fairly instant jumps in DEC

I see it happened a couple of times. I don't see it affecting RA, so it looks to me like something is loose in your imaging train for this guiding setup?




image.png



On Thu, Oct 14, 2021 at 9:47 AM Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:
Hello Nicholas,

The good news is that your mount is working fine. Both the RA periodic error curve and the Dec backlash curve are well within reason for this old mount. I don't see any sign of stiction in Dec, so it will guide quite well in that axis. RA is between 8 and 10 arc seconds, which is slightly out but not enough to cause any guiding problems. So, the mount is healthy and will be able to do imaging with a 6" refractor just fine. Your 6" is not too large for the Mach1. The mount can actually handle somewhat bigger scopes and guide well.

I do have some comments about your settings:

First, your high frequency star motion (seeing) is very high, you must be either experiencing some air flows from an east wind over the mountains, or your particular location is just not very steady for seeing (2.66 arc sec star motion as reported in your GA is very high). If it really is that high then your setting of Min Move (0.18 for RA and 0.23 for Dec)  is totally wrong and it shows in your RA Guider graph when you started guiding. Such a low setting of Min Move will cause oscillation back and forth as the guide software tries to chase the seeing. Your GA run recommended 0.39 for RA and 0.6 for Dec. I would start with those settings, but if the guide graph doesn't settle down I would increase RA to 0.5 or 0.6, same as Dec. There is no reason to try keeping the RA axis to such a low threshold as 0.18 arc seconds. When I am guiding even with my largest and longest scopes I rarely ever set the min Move below 0.3 arc seconds.

The other thing I would do is to set the aggressiveness for both axes to 50% when the seeing is not good, and only increase it to 70% under very good seeing conditions. Seeing is NOT transparency! Seeing is high frequency star motion or the back and forth motion that you record in the Dec axis when no guide pulses are being sent.

It is imperative that you Do Not set any backlash compensation in your guide software, and that you always use 1x guide rate. Normally I would guide with 2 to 3 second guide exposures. That will help to smooth out the star motion and minimize chasing the seeing.

You can guide with the present RA periodic error of 8 to 10 arc seconds since that occurs over a 6.4 minute cycle and is slow enough for your guide software to handle. However, if you ever want to really get your mount tracking well, then you might consider using PEMPro to create a PE curve and feed it to your CP controller. Then turn it on and watch the mount's RA tracking improve dramatically. However, it will only work if you do it right. If you mess up the measurement and don't follow the instructions, you can easily make things worse. It's up to you if you are confident that you can do it right. Even if you mess up, you can always turn the PE correction off.

Finally, Some of your previous runs show a very high Dec drift rate which is an indication that your Polar Alignment is quite a ways off. A Dec drift rate of 1 to 2 arc seconds in a 5 minute period would be ideal, in your case it was more than 10 times that amount, and this will limit your ability to get tight guiding and tight sharp stars. You will get all kinds of recommendations but just pick the one that works for you and stick with it. Polar alignment the same way each time will give you consistent results.

Good luck and fair skies.

Roland Christen
Astro-Physics Inc.





-----Original Message-----
From: nicholas via groups.io <chironik=yahoo.com@groups.io>
To: main@ap-gto.groups.io
Sent: Thu, Oct 14, 2021 2:49 am
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

I posted the GA ss above if that is what you mean.

there is this which Andrew generated of the test run n
I have not gotten to PEC yet. 

the attached Phd2 ss is from current guide about 25 minutes thereof.

--
Roland Christen
Astro-Physics



--
Brian 



Brian Valente


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Roland Christen
 

Hello Nicholas,

The good news is that your mount is working fine. Both the RA periodic error curve and the Dec backlash curve are well within reason for this old mount. I don't see any sign of stiction in Dec, so it will guide quite well in that axis. RA is between 8 and 10 arc seconds, which is slightly out but not enough to cause any guiding problems. So, the mount is healthy and will be able to do imaging with a 6" refractor just fine. Your 6" is not too large for the Mach1. The mount can actually handle somewhat bigger scopes and guide well.

I do have some comments about your settings:

First, your high frequency star motion (seeing) is very high, you must be either experiencing some air flows from an east wind over the mountains, or your particular location is just not very steady for seeing (2.66 arc sec star motion as reported in your GA is very high). If it really is that high then your setting of Min Move (0.18 for RA and 0.23 for Dec)  is totally wrong and it shows in your RA Guider graph when you started guiding. Such a low setting of Min Move will cause oscillation back and forth as the guide software tries to chase the seeing. Your GA run recommended 0.39 for RA and 0.6 for Dec. I would start with those settings, but if the guide graph doesn't settle down I would increase RA to 0.5 or 0.6, same as Dec. There is no reason to try keeping the RA axis to such a low threshold as 0.18 arc seconds. When I am guiding even with my largest and longest scopes I rarely ever set the min Move below 0.3 arc seconds.

The other thing I would do is to set the aggressiveness for both axes to 50% when the seeing is not good, and only increase it to 70% under very good seeing conditions. Seeing is NOT transparency! Seeing is high frequency star motion or the back and forth motion that you record in the Dec axis when no guide pulses are being sent.

It is imperative that you Do Not set any backlash compensation in your guide software, and that you always use 1x guide rate. Normally I would guide with 2 to 3 second guide exposures. That will help to smooth out the star motion and minimize chasing the seeing.

You can guide with the present RA periodic error of 8 to 10 arc seconds since that occurs over a 6.4 minute cycle and is slow enough for your guide software to handle. However, if you ever want to really get your mount tracking well, then you might consider using PEMPro to create a PE curve and feed it to your CP controller. Then turn it on and watch the mount's RA tracking improve dramatically. However, it will only work if you do it right. If you mess up the measurement and don't follow the instructions, you can easily make things worse. It's up to you if you are confident that you can do it right. Even if you mess up, you can always turn the PE correction off.

Finally, Some of your previous runs show a very high Dec drift rate which is an indication that your Polar Alignment is quite a ways off. A Dec drift rate of 1 to 2 arc seconds in a 5 minute period would be ideal, in your case it was more than 10 times that amount, and this will limit your ability to get tight guiding and tight sharp stars. You will get all kinds of recommendations but just pick the one that works for you and stick with it. Polar alignment the same way each time will give you consistent results.

Good luck and fair skies.

Roland Christen
Astro-Physics Inc.





-----Original Message-----
From: nicholas via groups.io <chironik@...>
To: main@ap-gto.groups.io
Sent: Thu, Oct 14, 2021 2:49 am
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

I posted the GA ss above if that is what you mean.

there is this which Andrew generated of the test run n
I have not gotten to PEC yet. 

the attached Phd2 ss is from current guide about 25 minutes thereof.

--
Roland Christen
Astro-Physics


Re: GoTos

Jodi McCullough <jmccul@...>
 

When we had this problem, it was one of the handpaddle batteries.  Call George at AP and he can send you the right part.  If I remember correctly, it was the wired battery.
Jodi


On Oct 13, 2021, at 10:24 AM, Michael Hamburg via groups.io <michael_hamburg44@...> wrote:


I truly love my AP900 GTO3 which I bought from the original owner a couple of years ago. However, I cannot get accurate GoTos no matter what I try. I use solely the had controller with the upgraded chip. I have synched, recalibrated, loosened  the clutches, issued GoTo commands, and retightened the clutches. I currently carry a Celestron Edge 11 HD with an Orion 80mm ED refractor piggybacked. The mount easily carries this set-up. So - is it 1) user error? 2) cone error (orthogonality?) 3) software bug? or 4) a nasty gremlin? Please help!

Michael HamburgEmoji


Re: Unexpected mount movement

 

Alex - 

were you guiding during this period, and if so can you provide the guidelog from that night?

I"m wondering if somehow it may have locked on to a different star, or something happened during dithering that caused it to do a major move within the guiding


Brian


Re: GoTos

Scott Cooke
 

Would love to see a picture of the side by side setup.  I have thought of doing something similar with my 900.
Thanks,
Scott

On Thu, Oct 14, 2021 at 1:03 AM <weems@...> wrote:
My 900 carries a C14 and 6” f9 side by side and generally gets within 10’ of the target (closer to 7’ when not into refraction near the horizon).  And it can slew from one side of the meridian to the other then be told to return to the starting object, and will get it within 1’.  The planets are a bit off, probably because of clock drift, as I haven’t set it since the DST change.  But It wasn’t close to that until I did a draft alignment for 30 minutes in each axis, and adjusted cone error to less than 1’. It’s on a 12” concrete pier, with a very short rat cage. I replaced the flexible Celestron dovetail with a Losmandy. Every mechanical connection is also really tightened up.

Chip


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

 

Sorry i'm a bit late to some of these comments

>>>>Another very important thing to know about PHD2:  If you manually rotate the camera after you calibrate PHD2 you need to calibrate it again. If you have an automated ASCOM rotator hooked up to PHD, I believe it can still use the previous calibration (since it knows about the rotation) but I have never relied on that feature, and I always recalibrate PHD even if it was my NiteCrawler that did the rotation for me.


Yes, PHD2 will correct for a rotator provided its connected and configured properly. 

I use it all the time for remote imaging and it works perfectly.



On Wed, Oct 13, 2021 at 9:12 AM Bill Long <bill@...> wrote:
The shift key on a desktop keyboard and the shift key on a laptop keyboard will do the same thing.

Like Roland, I do a fresh calibration every time I use the mount, even if it has been left outside and nothing has changed at all. I guess I can say I kind of cheat on that, as my automation does the PHD calibration for me every time the Voyager DragScript is run -- but the net effect is the same. I also check and tweak my Polar Alignment each night (before the calibration of course) but that just gives me something to do when I am waiting for the sky to darken up. 

Another very important thing to know about PHD2:  If you manually rotate the camera after you calibrate PHD2 you need to calibrate it again. If you have an automated ASCOM rotator hooked up to PHD, I believe it can still use the previous calibration (since it knows about the rotation) but I have never relied on that feature, and I always recalibrate PHD even if it was my NiteCrawler that did the rotation for me.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of nicholas via groups.io <chironik=yahoo.com@groups.io>
Sent: Tuesday, October 12, 2021 7:36 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO
 
I really appreciate the feedback. the entire community is enriched by your participation. 

That being said I do need to clarify something on this thread. As I have looked back at my guide screen, I was not only checking off " auto-restore."   I was  also  checking  "clear mount calibration."  In fact I think in my case auto-restore is always checked and before I begin guiding I check "clear mount calibration." I am quite sure I did so the other night. If this is  a way to calibrate, and I believe  it is, it seems more gratifying because from my perspective I can confirm the operation/command has been initiated. The shift click method, well, I just want to make sure it happens and the intended command is sent to Phd2 .  I have noticed with Windows laptops the functions are different from what they are on desktop keyboards. At least for keystrokes involving function keys.  Actually I am looking at my laptop, it has no function keys, just a top row of number keys. Likely this  has no affect with this shift click operation. But I am looking for the surfeit way to get the command to Phd2. And again I  am looking at my guide screen and auto restore calibration is checked off as a sort of default in my settings atleast. 



--
Brian 



Brian Valente


Re: ISS Tracked using APCC Pro v1.9

David Johnson
 

SkyTrack 1.5.1 is now available with continuous tracking for those mounts capable of it. I am trying it out inside with my Mach2, and it seems to work very well.  Of course, the real test will be under the stars (and satellites), but I’m not sure when the clouds are going to allow that to happen.


Re: GoTos

Michael Hamburg
 

I wish it was that simple.
Michael

Best wishes, Michael


On Wednesday, October 13, 2021, 04:47:53 PM EDT, J. Belden via groups.io <jjb4469@...> wrote:


My main problems with bad gotos with any of my AP mounts has been wrong time, wrong date.
DST Non DST as well

Joe






Re: GoTos

Michael Hamburg
 

Fernando,
Not only did I loosen the clutches, but I then retightened them. This rig never moves out my observatory!
Michael

Best wishes, Michael


On Wednesday, October 13, 2021, 03:01:33 PM EDT, fernandorivera3 via groups.io <fernandorivera3@...> wrote:


You have loosened the clutches? Don't you mean "tightened down" the clutches?
Try checking your location data in the keypad. Is it accurate or way off like maybe you accidentally left it set on coordinates from a distant star party?
What about the clock time? Is it on standard time rather than daylight savings? Maybe it could be incorrect time zone setting. 

Fernando


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

steve.winston@...
 

>in case you are wondering the GA was from the main imaging scope but now guiding is being performed w the small guide scope

For these tests it really is best to keep everything the same (i.e. don't switch between main and guide scope).

After switching back to the guide scope, did you re-do calibration and GA before starting guiding?

I don't see any evidence of a loose RA clutches in the data you uploaded, but just to be safe it's probably best to re-capture new data and this time just use your main imaging scope for the test:  Calibration, GA and then 20 minutes of guiding through the main scope after applying GA recommendations.

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