On Wed, Aug 18, 2021 at 10:53 PM, Roland Christen wrote:

Dec arc tracking is an independent model, not relying on the all-sky model. neither relies on the other to work.

 

By the way, for those who are keypad users, we also have similar model building in the latest keypad version. It does not use APCC, but can also create an accurate Dec arc model as well as an all-sky pointing/tracking model. It's more labor intensive, of course.

 

Rolando

Ah. very cool.  So it looks like this is just an additional step to do while waiting for astronomical night to get better tracking performance. 

I'm sure this will all become clear once I update and start exploring, but if imaging two objects in a given night, would you create two dec arc tracking models and so-on?

Seems like a really great feature!  Especially for those of us who do not have encoders.  I'm already reliably guiding below 0.4" RMS (0.3" RMS many nights) reliably, but why not eek out a little more precision.  Amazing stuff you are continuing to do. 

Hi,
After understanding the new payment method for the acquisition of new useful options (Purchase with 365 days latency rather than subscription), I am trying to understand how this option works. According to the manual (& 2.2) this is simple, because it corresponds to another method of calculating tracking correction which, with an active All-Sky model, allows better tracking on a declination arc. All you have to do is check the Enable ArcDec Tracking option.
The manual says:
"Enabling Dec-Arc tracking is as simple as setting a check box in APCC Pro. It can be enabled / disabled at any time which allows you to easily compare its tracking rate quality with that of the all-sky model."
There is therefore no new specific model to build.
So when Ray explains:
"Some notes about this:

1) Dec-Arc Tracking is only used for tracking rate calculations. The all-sky model, which is also calculated by APCC, still handles pointing.

2) Tracking rate correction only works within the area in which sky points are measured. When outside that area APCC uses the all-sky tracking rate model. The All-Sky model will also extrapolate outside of the sky data points that were collected. "

Does this mean that when the option is checked, a specific tracking model is calculated on the points of the declination arc closest to the active All-Sky model if one is used and to which the mount, unless the assertion "Tracking rate correction only works within the area in which sky points are measured" means something else which is not explained but as RAy also said "You do not need to collect new sky data to use the dec-arc tracking model. In fact you can switch between the all-sky tracking model and dec-arc tracking model by simply checking / unchecking a single checkbox while tracking. This allows you to compare the two models if you desire "je think the answer is yes?
Logic would dictate that unchecking, going to another Declination Arc, and re-checking would have the same effect for this new Arc. Is it correct?

Dominique

Thanks Ray.  The first post in this thread is an example of what I have been doing for a while.  So I am up to speed with you as far as getting APPM set up as per your example.  What derailed me was Roland’s statement that the new feature doesn’t use the “all sky model” and I was under the impression that your example is still technically an all sky model… but just an abbreviated all sky model.  Your example is appreciated.
--
Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/

I have pretty much been doing this for the last year as is shown in the first post in this thread. So I must not
understand some of the terminology or something. I’ll just keep on doing what I have been doing and then check the
Dec-Arc box too. :-)

Yes, the new dec-arc tracking feature is really that simple to use! :-)

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Dean Jacobsen
Sent: Wednesday, August 18, 2021 10:36 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Dec-Arc Tracking in APCC Pro v1.9 - an explainer please?

On Wed, Aug 18, 2021 at 10:20 PM, Ray Gralak wrote:


Typically you should have at least 5 points along each declination arc.

Since APPM collects data points along declination arcs, you only need to define a minimum and maximum
declination with at least two arcs that encompass the target(s) that you want to image.

BTW, collecting data along declination arcs like APPM has always done is no coincidence. It was done in
anticipation of APCC having the Dec-Arc tracking rate modeling scheme.

I have pretty much been doing this for the last year as is shown in the first post in this thread. So I must not
understand some of the terminology or something. I’ll just keep on doing what I have been doing and then check the
Dec-Arc box too. :-)

--
Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/
<https://www.astrobin.com/users/deanjacobsen/>

After upgrading does a new model need to be created to best take advantage of dec arc tracking, or will the old model
be sufficient? (Obsy mounted).

You do not need to collect new sky data to use the dec-arc tracking model. In fact you can switch between the all-sky tracking model and dec-arc tracking model by simply checking/unchecking a single checkbox while tracking. This allows you to compare the two models if you desire.

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Chris White
Sent: Wednesday, August 18, 2021 7:33 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Dec-Arc Tracking in APCC Pro v1.9 - an explainer please?

After upgrading does a new model need to be created to best take advantage of dec arc tracking, or will the old model
be sufficient? (Obsy mounted).

Also when uninstalling the previous version (I assume through windows control panel) do any steps need to be taken
to ensure setting are not lost? Should Profile and model be saved outside of their native folders prior to uninstall?

Thanks!

Hi Nick,

I have version 1.8 and I would like to demo the new features in 1.9. So will a 1.9 demo licence play fair with my 1.8
licence? Especially when the demo licence expires?

Yes, a trial license will work okay with 1.8.

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Nick Iversen
Sent: Wednesday, August 18, 2021 6:01 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] APCC v1.9 and one-year renewal subscriptions

I have version 1.8 and I would like to demo the new features in 1.9. So will a 1.9 demo licence play fair with my 1.8
licence? Especially when the demo licence expires?

On Wed, Aug 18, 2021 at 10:20 PM, Ray Gralak wrote:

Typically you should have at least 5 points along each declination arc.

Since APPM collects data points along declination arcs, you only need to define a minimum and maximum declination with at least two arcs that encompass the target(s) that you want to image.

BTW, collecting data along declination arcs like APPM has always done is no coincidence. It was done in anticipation of APCC having the Dec-Arc tracking rate modeling scheme.

I have pretty much been doing this for the last year as is shown in the first post in this thread.  So I must not understand some of the terminology or something.  I’ll just keep on doing what I have been doing and then check the Dec-Arc box too.   :-)
 
--
Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/

OK, I didn’t see Roland’s reply.  

Set up APPM to do one line, including both sides of the meridian.

My recollection is that when the data collection is finished, then APPM will ask me if I want to apply the data as an APCC model, which I always say “yes” to.

Do we also reply “yes” for the Dec-Arc tracking?

And then we have the Dec-Arc tracking box checked to enable the feature.

Simple.

I’ll read about it in the manual.  

--
Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/

Hi Mike,

I got my AP1100 at the start of April. I initially updated without uninstalling the previous version and everything looked
good until I checked the ELTIMA driver which indicated an older version. I uninstalled APCC Pro and reinstalled the
new version and again everything looks fine except for the ELTIMA driver.

That should have worked. What is the driver version shown in the properties window for an Eltima Virtual Port?

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of mikela via groups.io
Sent: Wednesday, August 18, 2021 3:09 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] APCC v1.9 and one-year renewal subscriptions #APCC

Hi Ray,

I got my AP1100 at the start of April. I initially updated without uninstalling the previous version and everything looked
good until I checked the ELTIMA driver which indicated an older version. I uninstalled APCC Pro and reinstalled the
new version and again everything looks fine except for the ELTIMA driver. Should I try to update the driver in the
properties window?

Mike

Typically you should have at least 5 points along each declination arc.

Since APPM collects data points along declination arcs, you only need to define a minimum and maximum declination with at least two arcs that encompass the target(s) that you want to image.

BTW, collecting data along declination arcs like APPM has always done is no coincidence. It was done in anticipation of APCC having the Dec-Arc tracking rate modeling scheme.

-Ray

--

Dominique,

Thank you very much by removing the protection I was able to install.

Perfect! I'm glad you got it installed!

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Dominique
Sent: Wednesday, August 18, 2021 1:51 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] APCC Pro 1.9.0.1 installation bug.

Hi Ray,
Thank you very much by removing the protection I was able to install.
I had never had this type of problem with this dll., Probably an evolution of the protection on my antivirus. I put the Dll
in the control exclusions so that it works without problems on the next version.
Regards
Dominique

Sébastien ,

You wrote:

Ray wote:

You found a subtle bug. :-) Try renaming the filename's extension from ".fits" to ".fit".

Yep, that did it.

Great! Thanks for confirming!

BTW, is there a place (other than through this forum) to report issues re APPC/APPM (or even enhancement
requests) that we could come across or is this the correct place to ask ?

This is the best place to post issues you encounter with APCC, APPM, Horizons, and the AP V2 ASCOM driver.

I'm asking because e.g. I also have some issues with the 3D viewer in APCC (mount position when parked is
"drifting") but maybe it is only specific to my system (or my bad understanding of what is "calibration with the
night sky"). Obviously, this isn't a show stopper either, but it would indeed be nice to have that feature working
as expected for me.

I'm going to need more details and perhaps log files to understand what you are observing.

-Ray

Use APPM to collect the data for your dec arc.

OK, I’m convinced it will work good.  But are you using the keypad or are you using it via APCC?  And if you are using via APCC, then what is involved in getting everything set up?  Do you need to collect data points via APPM?  Roland said the feature does not use the all sky model.  What data does the feature rely upon?
--
Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/

Dean

As an example I do 900sec subs unguided with just Dec Arc tracking @ 480mm on the ASI6200

https://www.brianvalentephotography.com/astrophotography/i-DwvmwzK/A

The tracking is so good that when i'm pixel peeping all i see is the slight backfocus issue that elongates my stars in the corners. 

Brian