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APPM Basic questions

ap@CaptivePhotons.com
 

Could someone give me a sanity check.

I image with a tear down and set up nightly.  I do it from fixed pavers that gives me a fairly good polar alignment but not precise (tonight I was unusually close about 6' off in each direction once assembled).  I then do a polar alignment with other software to get it good. 

Last time out I built a model.  I think I'm not supposed to do that when not in a permanent setup, right?   And unliked tPoint there's no "recalibrate" model run, you build from scratch. So if I cannot (or do not want) to build a model tonight, I should turn off the model corrections, right?   (If they don't default to off). 

Now tonight it's partly cloudy.  I'm building a model but I think probably 1/3 or more of the sky I will get failures.  It's still running.  

Let's assume I have a good polar alignment and have done a plate solve and recal from another program (probably a sync that became a recal). 

At what point is it better to use the model as opposed to dispose of it entirely, if clouds are the issue (i.e. and I am not going to get a better one)?  Am I better with nothing, or pretty much anything I can get?

OK... while writing this it finished.  12 failed, 28 good solves, most of the failures in the SE.  So... I'm going to load it just because, but... should I?  How good or bad (relative to how much of the sky) is needed before the model does more good than harm?  Or is the answer it ALWAYS does more good than harm to pointing and tracking accuracy? 

Linwood

PS. I image, I guide, I realize that the model is less relevant to me, but I'm trying to learn good practices for using it, who knows, might do some unguided imaging at some point.
ap@CaptivePhotons.com
 

Apologies, there’s a misleading sentence my fingers failed to translate right from my brain:

 

>> Last time out I built a model.  I think I'm not supposed to use that model tonight when not in a permanent setup, right?   

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of ap@... via groups.io
Sent: Saturday, August 7, 2021 9:29 PM
To: main@ap-gto.groups.io
Subject: [ap-gto] APPM Basic questions

 

Could someone give me a sanity check.

I image with a tear down and set up nightly.  I do it from fixed pavers that gives me a fairly good polar alignment but not precise (tonight I was unusually close about 6' off in each direction once assembled).  I then do a polar alignment with other software to get it good. 

Last time out I built a model.  I think I'm not supposed to do that when not in a permanent setup, right?   And unliked tPoint there's no "recalibrate" model run, you build from scratch. So if I cannot (or do not want) to build a model tonight, I should turn off the model corrections, right?   (If they don't default to off). 

Now tonight it's partly cloudy.  I'm building a model but I think probably 1/3 or more of the sky I will get failures.  It's still running.  

Let's assume I have a good polar alignment and have done a plate solve and recal from another program (probably a sync that became a recal). 

At what point is it better to use the model as opposed to dispose of it entirely, if clouds are the issue (i.e. and I am not going to get a better one)?  Am I better with nothing, or pretty much anything I can get?

OK... while writing this it finished.  12 failed, 28 good solves, most of the failures in the SE.  So... I'm going to load it just because, but... should I?  How good or bad (relative to how much of the sky) is needed before the model does more good than harm?  Or is the answer it ALWAYS does more good than harm to pointing and tracking accuracy? 

Linwood

PS. I image, I guide, I realize that the model is less relevant to me, but I'm trying to learn good practices for using it, who knows, might do some unguided imaging at some point.

Bill Long
 

I always use a model if I'll have the gear out for more than one night. When I'm doing a single night only, that's usually me testing some gear out working out some kinks and the model wouldn't be useful anyhow. They don't take long to make though and I can usually get them done before it's dark enough to start getting data anyhow.

From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of ap@... <ap@...>
Sent: Saturday, August 7, 2021 6:30 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] APPM Basic questions
 

Apologies, there’s a misleading sentence my fingers failed to translate right from my brain:

 

>> Last time out I built a model.  I think I'm not supposed to use that model tonight when not in a permanent setup, right?   

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of ap@... via groups.io
Sent: Saturday, August 7, 2021 9:29 PM
To: main@ap-gto.groups.io
Subject: [ap-gto] APPM Basic questions

 

Could someone give me a sanity check.

I image with a tear down and set up nightly.  I do it from fixed pavers that gives me a fairly good polar alignment but not precise (tonight I was unusually close about 6' off in each direction once assembled).  I then do a polar alignment with other software to get it good. 

Last time out I built a model.  I think I'm not supposed to do that when not in a permanent setup, right?   And unliked tPoint there's no "recalibrate" model run, you build from scratch. So if I cannot (or do not want) to build a model tonight, I should turn off the model corrections, right?   (If they don't default to off). 

Now tonight it's partly cloudy.  I'm building a model but I think probably 1/3 or more of the sky I will get failures.  It's still running.  

Let's assume I have a good polar alignment and have done a plate solve and recal from another program (probably a sync that became a recal). 

At what point is it better to use the model as opposed to dispose of it entirely, if clouds are the issue (i.e. and I am not going to get a better one)?  Am I better with nothing, or pretty much anything I can get?

OK... while writing this it finished.  12 failed, 28 good solves, most of the failures in the SE.  So... I'm going to load it just because, but... should I?  How good or bad (relative to how much of the sky) is needed before the model does more good than harm?  Or is the answer it ALWAYS does more good than harm to pointing and tracking accuracy? 

Linwood

PS. I image, I guide, I realize that the model is less relevant to me, but I'm trying to learn good practices for using it, who knows, might do some unguided imaging at some point.

Ray Gralak
 

Hi Linwood,

Have you already read the APCC help section for APPM? There's lots of information in there that can get you started.

If you don’t tear down or significantly change your setup, you can usually use the same model for many nights. However, if the model starts to become inaccurate, then you may need to redo it. For example, if the polar alignment changes because of mount settling, or the temperature change is significant enough to measurably change equipment flexure.

BTW, if it is just shifting polar alignment causing an issue, you might try tweaking polar alignment outside of APCC (e.g. via PEMPro, SharpCap, PHD2, polar alignment scope, etc.). Then do a RECAL in APPM, and the model should work well again.

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of ap@...
Sent: Saturday, August 7, 2021 6:29 PM
To: main@ap-gto.groups.io
Subject: [ap-gto] APPM Basic questions

Could someone give me a sanity check.

I image with a tear down and set up nightly. I do it from fixed pavers that gives me a fairly good polar alignment
but not precise (tonight I was unusually close about 6' off in each direction once assembled). I then do a polar
alignment with other software to get it good.

Last time out I built a model. I think I'm not supposed to do that when not in a permanent setup, right? And
unliked tPoint there's no "recalibrate" model run, you build from scratch. So if I cannot (or do not want) to build a
model tonight, I should turn off the model corrections, right? (If they don't default to off).

Now tonight it's partly cloudy. I'm building a model but I think probably 1/3 or more of the sky I will get failures. It's
still running.

Let's assume I have a good polar alignment and have done a plate solve and recal from another program
(probably a sync that became a recal).

At what point is it better to use the model as opposed to dispose of it entirely, if clouds are the issue (i.e. and I am
not going to get a better one)? Am I better with nothing, or pretty much anything I can get?

OK... while writing this it finished. 12 failed, 28 good solves, most of the failures in the SE. So... I'm going to load it
just because, but... should I? How good or bad (relative to how much of the sky) is needed before the model does
more good than harm? Or is the answer it ALWAYS does more good than harm to pointing and tracking
accuracy?

Linwood

PS. I image, I guide, I realize that the model is less relevant to me, but I'm trying to learn good practices for using it,
who knows, might do some unguided imaging at some point.
ap@CaptivePhotons.com
 

Ray wrote:

 

  • Have you already read the APCC help section for APPM? There's lots of information in there that can get you started.

 

I read the manual (twice), but probably not the help file, I take it that’s different than the manual.  Tomorrow...

 

My main question, as related to this night, was I could only model 2/3rds of the sky, and was wondering if using that model was helpful, or pointless.  I’ll hopefully find guidance in the help file tomorrow.  Pulled it all in tonight, it got “clear” but so hazy there was no point in imaging.

 

  • If you don’t tear down or significantly change your setup, you can usually use the same model for many nights. However, if the model starts to become inaccurate, then you may need to redo it. For example, if the polar alignment changes because of mount settling, or the temperature change is significant enough to measurably change equipment flexure.

 

I do tear down completely.  I try to reproduce the same setup by setting the tripod legs into drilled holes, but there’s always some slop from wheeling it in and out, removing and reinstalling the OTA, etc.   I have no faith a prior model would be valid.  Maybe I can do some on consecutive nights and see how they vary.

 

  • BTW, if it is just shifting polar alignment causing an issue, you might try tweaking polar alignment outside of APCC (e.g. via PEMPro, SharpCap, PHD2, polar alignment scope, etc.). Then do a RECAL in APPM, and the model should work well again.

 

I do a polar alignment first thing, either Sharpcap or NINA (they do agree).

 

Thanks for the response.

 

Linwood

 
Ray Gralak
 

My main question, as related to this night, was I could only model 2/3rds of the sky, and was wondering if using
that model was helpful, or pointless. I’ll hopefully find guidance in the help file tomorrow. Pulled it all in tonight, it
got “clear” but so hazy there was no point in imaging.
No one can tell you that because every setup is different. However, you can try using the model afterwards to see how it performs.

I do tear down completely. I try to reproduce the same setup by setting the tripod legs into drilled holes, but there’s
always some slop from wheeling it in and out, removing and reinstalling the OTA, etc. I have no faith a prior
model would be valid. Maybe I can do some on consecutive nights and see how they vary.
If you can reproduce the position of everything, especially polar alignment, then the model should be re-usable. Only be actually trying this will you know.

-Ray


-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of ap@...
Sent: Saturday, August 7, 2021 9:55 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] APPM Basic questions

Ray wrote:



* Have you already read the APCC help section for APPM? There's lots of information in there that can get
you started.



I read the manual (twice), but probably not the help file, I take it that’s different than the manual. Tomorrow...



My main question, as related to this night, was I could only model 2/3rds of the sky, and was wondering if using
that model was helpful, or pointless. I’ll hopefully find guidance in the help file tomorrow. Pulled it all in tonight, it
got “clear” but so hazy there was no point in imaging.



* If you don’t tear down or significantly change your setup, you can usually use the same model for many
nights. However, if the model starts to become inaccurate, then you may need to redo it. For example, if the polar
alignment changes because of mount settling, or the temperature change is significant enough to measurably
change equipment flexure.



I do tear down completely. I try to reproduce the same setup by setting the tripod legs into drilled holes, but there’s
always some slop from wheeling it in and out, removing and reinstalling the OTA, etc. I have no faith a prior
model would be valid. Maybe I can do some on consecutive nights and see how they vary.



* BTW, if it is just shifting polar alignment causing an issue, you might try tweaking polar alignment outside of
APCC (e.g. via PEMPro, SharpCap, PHD2, polar alignment scope, etc.). Then do a RECAL in APPM, and the
model should work well again.



I do a polar alignment first thing, either Sharpcap or NINA (they do agree).



Thanks for the response.



Linwood
ap@CaptivePhotons.com
 

Ray/Linwood Wrote:

 

  • Have you already read the APCC help section for APPM? There's lots of information in there that can get you started.

 

  • I read the manual (twice), but probably not the help file, I take it that’s different than the manual.  Tomorrow...

 

Excellent pointer.  I found all sorts of tidbits in there I had to discover otherwise.  I thought I had prepared by reading the manual (usually the help file is just portions of a manual).  Lesson learned. Read all of APPM, now going back to APCC.

 

Thank you.

 

  • My main question, as related to this night, was I could only model  2/3rds of the sky, and was wondering if using that model was helpful, or pointless.  I’ll hopefully find guidance in the help file tomorrow.  Pulled it all in tonight, it got “clear” but so hazy there was no point in imaging.

 

  • No one can tell you that because every setup is different. However, you can try using the model afterwards to see how it performs.

 

Fair enough.  In reading the help file I also see how you can test a model by running shorter pointing runs to see the accuracy.  Nice.

 

I also compared my small model to an even smaller (due to clouds) and max error was almost double on the cloudy one.  So at least intuitively that makes sense.  (Still pretty small though).

 

One last question (ok, probably never such a thing)… is there a document that explains more about the meaning of the various model properties.  Or maybe what I am asking is whether any of those values are actionable for a user – if my Tube Flexure quadrupled (for example) with the same gear, does that tell me to DO anything?   Or are these more essentially constants in a very complex curve fit designed to minimize pointing errors, and despite real world derivation may not individually mean anything?

 

Linwood

 

PS. If the clouds would abate I would be less interested in theory.  😊   Last night I waited about 3.5 hours and it stayed high hazy clouds, so I pulled everything in early.  But at least I got to practice.  Despite the clouds guiding around 0.3” steadily.  Goto landed the target right in the center (at least to the eye). Darn fine hardware/software!
ap@CaptivePhotons.com
 

Linwood wrote:

 

  • One last question (ok, probably never such a thing)… is there a document that explains more about the meaning of the various model properties.  Or maybe what I am asking is whether any of those values are actionable for a user – if my Tube Flexure quadrupled (for example) with the same gear, does that tell me to DO anything?   Or are these more essentially constants in a very complex curve fit designed to minimize pointing errors, and despite real world derivation may not individually mean anything?

 

So I started reading the APCC help file and found definitions of these values.  I really need a 30 minute delay on emails.  😊

 

READ THE HELP FILES NOT JUST THE MANUALS.  I’ll have that printed large somewhere near my monitor. 

 

Sigh… sorry for the interruptions.

 
Joe Zeglinski
 

Hi Linwood,
 
    I keep wondering why you haven’t yet printed the actual HELP file. It is very well written and a pleasant read.  You can do that with most help files, as I have done. Prints as a PDF document.
 
    I prefer reading printed documents rather than boob-tube screens, unless I am in a hurry and need to enter a search word for faster “specific”  references - much like referencing the Index volume of a set of Encyclopaedias  :-)
 
   But then,  I’m “old school”.  Check into it.
 
Joe
 

From: ap@...
Sent: Sunday, August 8, 2021 1:54 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] APPM Basic questions
 

Linwood wrote:

 

  • One last question (ok, probably never such a thing)… is there a document that explains more about the meaning of the various model properties.  Or maybe what I am asking is whether any of those values are actionable for a user – if my Tube Flexure quadrupled (for example) with the same gear, does that tell me to DO anything?   Or are these more essentially constants in a very complex curve fit designed to minimize pointing errors, and despite real world derivation may not individually mean anything?

 

So I started reading the APCC help file and found definitions of these values.  I really need a 30 minute delay on emails.  😊

 

READ THE HELP FILES NOT JUST THE MANUALS.  I’ll have that printed large somewhere near my monitor. 

 

Sigh… sorry for the interruptions.

 
ap@CaptivePhotons.com
 

Joe Zeglinski said:

 

  •     I keep wondering why you haven’t yet printed the actual HELP file. It is very well written and a pleasant read.  You can do that with most help files, as I have done. Prints as a PDF document.

 

  •     I prefer reading printed documents rather than boob-tube screens, unless I am in a hurry and need to enter a search word for faster “specific”  references - much like referencing the Index volume of a set of Encyclopaedias  :-)

 

We are somewhat the opposite.  By far I prefer to read on line, especially since something will trigger a thought, and I can do a text search in seconds rather than paging through … well, pages.

 

In this case my issue was I did not realize the help file was useful.  Most software I get the help file is somewhere from empty to a copy of the manual – if there even is a manual.  All too often it is a “just run it, it will be obvious” attitude.

 

I do have a printer.  Have to print UPS labels on something.  😊

 

  •    But then,  I’m “old school”.  Check into it.

 

I’m old.  And I went to school.  😊

 

Sometimes I even went to class. Though I confess to taking Astronomy 101 as a General Educational Elective (as opposed to say, Art History, in which I might have committed suicide).

 

I really do like reading manuals.  My earliest professional computer work was with DEC VMS, and it had a huge Orange Wall of binders of manuals (yes, paper, but who imagined Kindles then).  Now you get most products with a “quick start guide”, often in bad translations and obsolete by when you get it.

 

Glad to see AP actually HAS manuals.  Well, and Help Files.  Mea Culpa.

 

A big problem I have with manuals is they often are bad at “why”.  They frequently tell you “what”, sometimes “how”, but rarely explain the rationale behind it.  Got to give AP credit – their manuals (and help) come much closer to injecting  “Why” in there (you could always add a bit more, of course).

 

Linwood

 
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