Date   

Re: Crescent Nebula

Stuart <stuart.j.heggie@...>
 

Nicely done Michael!


On Wed, 22 Jul 2020 at 13:26, Michael Dolenga via groups.io <giroditalia=yahoo.com@groups.io> wrote:


--

Stuart
http://www.astrofoto.ca/stuartheggie/


Re: Crescent Nebula

Karen Christen
 

I like that, Mike.  It has an ephemeral quality. 

 

I still think it should be called the Brain Nebula.  :-D

Karen

AP

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Michael Dolenga via groups.io
Sent: Wednesday, July 22, 2020 12:26 PM
To: main@ap-gto.groups.io
Subject: [ap-gto] Crescent Nebula

 

Taken from my backyard in the Seattle area over the past two weeks: Crescent Nebula HOO bicolor

 

 


Crescent Nebula HOO bicolor

14 hours O3 (30 minute subs) 11 hours HA (30 minute subs) DSI RC10C telescope AP 900GTO mount FLI ML8300 camera...

 

 

Michael

 

 

 

 


--
Karen Christen
Astro-Physics


Crescent Nebula

Michael Dolenga
 


Re: More unguided images with the Mach2 and APCC Pro #APCC #Mach2GTO

Dean Jacobsen
 

Thanks for taking a look gentlemen.
--
Dean Jacobsen
http://astrophoto.net/wp/
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Re: FITS Image Header Issues Using APPM-Help!

Worsel
 


Re: More unguided images with the Mach2 and APCC Pro #APCC #Mach2GTO

lmbrabec@...
 

Really impressive Dean!  All the best, Scott


Re: FITS Image Header Issues Using APPM-Help!

lmbrabec@...
 

So I tried a couple of things today to try and figure out this puzzle of plate solve failures:

1) I tried using the ASCOM V2 simulator camera in APPM.  I did a Plate Solve in APPM on the Run tab, it showed an image (FITS file), and then plate solving failed with same error message.  The FITS image header looks the same as past failed images.  No luck here.  I'm running ASCOM version 6.4.1.2695.  I also noticed that there was an update on the ASCOM  app on my computer on 5/9/2020.

2) I uninstalled the ZWO ASCOM camera driver (I'm using a ZWO ASI294MC Pro camera), then re-installed it (ZWO latest camera ASCOM driver version 1.0.4.3) and restarted my computer.  I did a Plate Solve in APPM on the Run tab, it show and image (FITS file), and then plate solving failed with same error message.  The FITS image header looks the same as past failed images.  No luck here.

3) I had run the NASA Skyview (Internet) camera option in APPM and ran a small model (38 pts).  This plate solved like a champ.  No issues, except I wish I could use the data to run a model!  The FITS file image header is full of information and in proper format as it plate solved great.  I'm using the latest version of PinPoint for plate solving.

I'm not sure what to try next but I'm starting to get suspicious of the ASCOM software but I could be barking up the wrong tree.  Sounds like Ray is recommending to hold of on going to the latest release (6.5) from what I gather at this point.  I thought about uninstalling my present version of ASCOM and reloading it but I'm not having any luck finding it on the ASCOM website (version 6.4.1.2695).

Any thoughts or ideas?  Thanks in advance for any help, Scott


Re: NGC6960

Michael Hamburg
 

Great shot!


On Tue, Jul 21, 2020 at 2:46 PM, Stuart
<stuart.j.heggie@...> wrote:
Nice work Mike! Big target - you did well to squeeze it in!


On Tue, 21 Jul 2020 at 13:45, Mike Dodd <mike@...> wrote:
I've long been attracted to the Veil Nebula, but never could image
NGC6960, The Witch's Broom, because my old ST-8 CCD camera bloomed the
bright star. But my current ASI1600MCP one-shot color CMOS camera
doesn't bloom, so now this target is in play.

Recently I managed to acquire nearly 5 hours of data over three rare
clear nights, and hope to get another 3-4 hours when the sky clears
again. Here's what I have so far:
<http://astronomy.mdodd.com/nebulae-17.html>

I rotated the camera to capture as much of the "broom" as possible on
the sensor, corner-to-corner. I never knew there was so much faint H-a
nebulosity close-by. Maybe additional data will reveal more.

Comments and suggestions welcome.

TMB-130SS APO @ f/7 on an AP1200.

--- Mike
http://astronomy.mdodd.com





--

Stuart
http://www.astrofoto.ca/stuartheggie/


Re: Can't connect to mount

Woody Schlom
 

Spares are a good thing.  I highly recommend them.

 

I’m holding off on the CP4.  So far, I’m more than fine with the CP3 on my Mach1.  And I sure can’t afford a Mach2 at the moment.

 

Woody

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of CurtisC via groups.io
Sent: Tuesday, July 21, 2020 2:19 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Can't connect to mount

 

Well, Woody, this issue would be a motivation to spring for CP4.  Funny thing, my Keyspan appeared to crash back in January, and I bought the FTDI in desparation to replace it.  So now the FTDI doesn't work, and the Keyspan has saved me.


Re: Can't connect to mount

CurtisC
 
Edited

Well, Woody, this issue would be a motivation to spring for CP4.  Funny thing, my Keyspan appeared to crash back in January, and I bought the FTDI in desperation to replace it.  So now the FTDI doesn't work, and the Keyspan has saved me.


Re: C11HD on Mach2 #Mach2GTO

Michael Dolenga
 

Nice shots Dominique. I especially like M13, always a favorite of mine. Your photo reminds me of the time I looked at it through at 20+ inch Dobsonian, really amazing.

Michael



On Tuesday, July 21, 2020, 01:25:54 PM PDT, Dominique Durand via groups.io <dom33.durand@...> wrote:


[Edited Message Follows]

Hi,
Here is a little feedback on the use of my Mach2.
The modeling goes pretty well with SGP / Platesolve2.
After photoshoots with the AP130GT, I switched to the C11HD with still use without autoguiding. With 1960 focal length with the reducer or 2800 focal length without the reducer, the quality of monitoring must be up to par.
Here are 2 clusters M13 and M92 made with exposures of 60 seconds and a galaxy NGC6384 made with exposures of 180 seconds.
The problems to be solved are more at the level of C11 than Mach2.
M13
https://astrob.in/full/h1sgqo/0/

M92
https://astrob.in/full/vfeboh/0/

NGC6384
https://astrob.in/full/5c5wt2/F/

Happy amateur astronut
Dominique


Re: Mount coordinates change while autoguiding

Michael Dolenga
 

DOH! I completely forgot about the collimation screws. I installed it in the mount ages ago and it's been there ever since. 

That said, given that I usually shoot from either my lumpy, mole infested backyard or remotely, guaranteeing good levelling isn't always the case. The extra validation from Sharpcap is helpful.

Michael


On Tuesday, July 21, 2020, 11:49:57 AM PDT, uncarollo2 <chris1011@...> wrote:



Back in RAPAS, Polaris was noticeably out of place.
Yes, and then you adjust the RAPAS via the 3 collimation screws to put Polaris where it should be, and then you have a RAPAS that can recreate that perfect polar alignment in about 10 seconds next time you set up. That's the whole idea about the collimation screws on the RAPAS.

Rolando


-----Original Message-----
From: Michael Dolenga via groups.io <giroditalia@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 21, 2020 1:44 pm
Subject: Re: [ap-gto] Mount coordinates change while autoguiding

I got the Polemaster camera, and used it with SharpCap. After careful alignment with the RAPAS, sharpcap reported an error of about 5 arcminutes, which it categorizes as "poor." A few minutes with the app and it was down to 11 arc seconds error. Back in RAPAS, Polaris was noticeably out of place. The imaging session I did last night showed at most 5 arc seconds of drift per hour over a 4 hour period, so clearly there was an improvement, although that's anecdotal at best. And I don't see any improvement on the images, I think we're seeing limited here in Seattle. Actually, cloud limited. :)

Michael



On Saturday, July 18, 2020, 09:39:18 AM PDT, uncarollo2 <chris1011@...> wrote:



Btw, is a 1 minute DEC drift over 1 hour at a declination of about 40 degrees good/bad?
The mount itself doesn't move in Dec, so all drift is due to external errors (atmospheric refraction, differential flexure, polar misalignment). Most Dec drift is simple polar misalignment in azimuth when pointing overhead and altitude misalignment when pointing towards the east or west.

Is 1 minute drift good/bad - I think that's bordering on excessive and can be easily fixed using PEMPro drift alignment. Good alignment back in the "good ol' days" was 1 arc sec drift per 5 minutes. That's back in my day when we used to walk uphill to school thru 5 foot snow drifts, and uphill again home.

Rolando


-----Original Message-----
From: Michael Dolenga via groups.io <giroditalia@...>
To: main@ap-gto.groups.io
Sent: Sat, Jul 18, 2020 11:27 am
Subject: Re: [ap-gto] Mount coordinates change while autoguiding

You do need to recalibrate after flipping to account for orthogonality errors. And you'd have to slew to the same coordinates reported by the mount just before you flip, which differ from the target. It's not really an issue once you understand what is happening, and luckily the software I'm using, NINA, does a plate solve after flipping and re-slews, if necessary, to your original target coordinates which it has preserved. I raise the question because until I understood how NINA worked, I thought the drift on the mount was problematic.

When I was doing flips manually, I would calibrate before flipping to reset the mount's coordinates to match my target, as Ray suggested.

Btw, is a 1 minute DEC drift over 1 hour at a declination of about 40 degrees good/bad? 1850 mm scope. Polar aligned using RAPAS.


Michael



On Saturday, July 18, 2020, 09:06:43 AM PDT, uncarollo2 <chris1011@...> via groups.io <chris1011@...> wrote:



The meridian flip automation i use includes a re-centering of the target via plate solve, which I think is pretty common
When you are autoguiding the target is always centered so no plate solve is needed. Because of the guide commands, the internal co-ordinates slowly drift, so at the end of the session you simply do a recal which brings the actual and commanded co-ordinates back together.

Rolando


-----Original Message-----
From: Brian Valente <bvalente@...>
To: main@ap-gto.groups.io
Sent: Sat, Jul 18, 2020 10:52 am
Subject: Re: [ap-gto] Mount coordinates change while autoguiding

>>> If I leave the mount running with no autoguider connected at all, RA and DEC remain constant, as I would expect. 

But likely the fov would have change significantly, so your target would have drifted out of frame

 >>>This confounds automated meridian flips because the mount "thinks" it is pointed somewhere other than where it actually is. Often, the difference is too slight to be significance, but sometimes not. 

The meridian flip automation i use includes a re-centering of the target via plate solve, which I think is pretty common


Brian


On Sat, Jul 18, 2020 at 8:48 AM uncarollo2 <chris1011@...> via groups.io <chris1011=aol.com@groups.io> wrote:

It seems as though the autoguider commands are being interpreted as user initiated slews.
Yes, autoguider commands are essentially user initiated moves which cause the mount to go to a new coordinate every time a move command is issued. This is universal and applies to every mount ever made, whether AP mount or other brands. They will all do the same.

Rolando


-----Original Message-----
From: Michael Dolenga via groups.io <giroditalia=yahoo.com@groups.io>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Sat, Jul 18, 2020 9:31 am
Subject: [ap-gto] Mount coordinates change while autoguiding

I've noticed that my 900GTO's coordinates, as reported by ASCOM (latest version of the driver) change over a session where I am autoguiding. This occurs whether using MaximDL or NINA/PhD. In both cases, I am configured to send autoguider commands via the ASCOM driver rather than a separate ST4 cable.

This confounds automated meridian flips because the mount "thinks" it is pointed somewhere other than where it actually is. Often, the difference is too slight to be significance, but sometimes not. 

As an example, last night I was doing 30 minute shots of the Crescent Nebula. Over one hour, as reported by the RA/DEC fields written into the FITS header, I saw a difference of 6 minutes, 4 seconds in RA and 1 minute 7 seconds in DEC.

If I leave the mount running with no autoguider connected at all, RA and DEC remain constant, as I would expect.

Is this expected behavior or am I possibly missing some configuration option? It seems as though the autoguider commands are being interpreted as user initiated slews.


Michael


--
Brian 



Brian Valente


Re: More unguided images with the Mach2 and APCC Pro #APCC #Mach2GTO

Roland Christen
 

That combination of scope and mount is doing an amazing job.

Rolando



-----Original Message-----
From: Dean Jacobsen <deanjacobsen@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 21, 2020 2:52 pm
Subject: [ap-gto] More unguided images with the Mach2 and APCC Pro #Mach2GTO #APCC

Hi All,

I have myself back into the unguided imaging grove with the Mach2.  Unless I mis-configure my Sequence Generator Pro/PlateSolve2 profile again.  ;-)

I couldn't be happier with the Mach2 and the software package.  I have been using AP mounts for a long time and this mount/software package is the best by far.

I set up the mount and break it down for each session so, instead of doing an all sky APPM point map run I have just been doing a 3 line point map that covers the declination of the object for the night.  For instance, if the object is at +20 declination I will set up APPM to map 10 points along each of +25, +20, and +15 declination.  This turns out to be about 33 or 34 points taking into account the double mapping of points within the west side meridian limits I have set up.  It takes about 20 to 30 minutes depending on how PlateSolve2 feels that night.

I suspect that I am taking more points than I need to but I want to make sure that the night is not wasted so I err on the side of caution.

Here are a couple of links to unguided images from the last two sessions:

https://www.astrobin.com/a5vp4q/

and

https://www.astrobin.com/h3kenj/

The good folks at AP have really done a nice job with the Mach2.

--
Dean Jacobsen
http://astrophoto.net/wp/
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Re: More unguided images with the Mach2 and APCC Pro #APCC #Mach2GTO

Stuart <stuart.j.heggie@...>
 

Dean, both are very nice shots but "The Coathanger" aka Brocchi's Cluster is my favourite.


On Tue, 21 Jul 2020 at 15:52, Dean Jacobsen <deanjacobsen@...> wrote:
Hi All,

I have myself back into the unguided imaging grove with the Mach2.  Unless I mis-configure my Sequence Generator Pro/PlateSolve2 profile again.  ;-)

I couldn't be happier with the Mach2 and the software package.  I have been using AP mounts for a long time and this mount/software package is the best by far.

I set up the mount and break it down for each session so, instead of doing an all sky APPM point map run I have just been doing a 3 line point map that covers the declination of the object for the night.  For instance, if the object is at +20 declination I will set up APPM to map 10 points along each of +25, +20, and +15 declination.  This turns out to be about 33 or 34 points taking into account the double mapping of points within the west side meridian limits I have set up.  It takes about 20 to 30 minutes depending on how PlateSolve2 feels that night.

I suspect that I am taking more points than I need to but I want to make sure that the night is not wasted so I err on the side of caution.

Here are a couple of links to unguided images from the last two sessions:

https://www.astrobin.com/a5vp4q/

and

https://www.astrobin.com/h3kenj/

The good folks at AP have really done a nice job with the Mach2.

--
Dean Jacobsen
http://astrophoto.net/wp/
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


--

Stuart
http://www.astrofoto.ca/stuartheggie/


More unguided images with the Mach2 and APCC Pro #APCC #Mach2GTO

Dean Jacobsen
 

Hi All,

I have myself back into the unguided imaging grove with the Mach2.  Unless I mis-configure my Sequence Generator Pro/PlateSolve2 profile again.  ;-)

I couldn't be happier with the Mach2 and the software package.  I have been using AP mounts for a long time and this mount/software package is the best by far.

I set up the mount and break it down for each session so, instead of doing an all sky APPM point map run I have just been doing a 3 line point map that covers the declination of the object for the night.  For instance, if the object is at +20 declination I will set up APPM to map 10 points along each of +25, +20, and +15 declination.  This turns out to be about 33 or 34 points taking into account the double mapping of points within the west side meridian limits I have set up.  It takes about 20 to 30 minutes depending on how PlateSolve2 feels that night.

I suspect that I am taking more points than I need to but I want to make sure that the night is not wasted so I err on the side of caution.

Here are a couple of links to unguided images from the last two sessions:

https://www.astrobin.com/a5vp4q/

and

https://www.astrobin.com/h3kenj/

The good folks at AP have really done a nice job with the Mach2.

--
Dean Jacobsen
http://astrophoto.net/wp/
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Re: Mach2 Keypad

 

Dean,

 

The Mach2 fits into the ADATRI, so  it sounds like you are all set.

 

Clear Skies,

 

Marj Christen

Astro-Physics, Inc

11250 Forest Hills Rd

Machesney Park, IL 61115

Phone: 815-282-1513

Fax: 815-282-9847

www.astro-physics.com

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Dean Jacobsen
Sent: Tuesday, July 21, 2020 12:33 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Mach2 Keypad

 

On Mon, Jul 20, 2020 at 05:25 PM, Michael Dolenga wrote:

Another question, is the Mach 2 base the same as a 2011 series 900GTO base? Basically, can I use the same tripod?

Michael, my standard 900 mounting plate already had the three bolt pattern for the ADATRI tripod adapter.  It was just a matter of bolting the ADATRI onto my existing 900 plate.
 
--
Dean Jacobsen
http://astrophoto.net/wp/
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Re: Mach1 and GTOCP4 Yellow Light

Mikko Viljamaa
 

Here's the link for the video; https://drive.google.com/file/d/1XaoLKrcg-IDLt4CfK7N3HrpyfOaboHlg/view?usp=sharing

I haven't heard yet if I should send the Mount back to AP or if this is something I can try to fix myself.


- Mikko


Re: Tracking w/ Passil 4 polar alignment

Christopher Erickson
 

And for FWIW, I have a big, heavy/1.5kg+ (and sharp!) Nikkor 80-400mm AF-S ED zoom lens and if I want to try to image the sky with it, I have to add a Losmandy DVR108 Guide Scope ring to the plate, near the front end of the lens to keep it rigid and stable. The thing will sag/flex/shift quite a bit under its own weight when mounted on it's integral tripod shoe. I assume there are a lot of floating parts inside of that big zoom lens, fighting gravity. If I am using two or more cams on a long plate, I have the telephoto set up rigidly with a secondary lens support and the cams with shorter lenses go on ball heads on the plate. Most ball-heads have a lot of flex so I only put 58mm or shorter lenses on them. My favorite lenses for the second and third cams are 20mm ultra-wide and a 10mm fisheye.

I hope this helps.

Virus-free. www.avg.com


On Tue, Jul 21, 2020 at 8:27 AM uncarollo2 <chris1011@...> via groups.io <chris1011=aol.com@groups.io> wrote:
Even if the polar alignment is spot on you will need to use a PEM curve.  I'm guessing here because you did not provide enough information to go on. For instance, what direction did the trailing go, where in the sky did you image. There is no information on how the scope is being held, or the camera, or whether there is focuser sag. Lots of things can add up to give poor results.

Rolando



-----Original Message-----
From: Wiggins, Rick <rickwiggins@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 21, 2020 12:58 pm
Subject: Re: [ap-gto] Tracking w/ Passil 4 polar alignment

Hi Roland,
I did setup using the pasill4 polar scope and got good alignment on the two stars through the polar scope. I did not use a PE curve. Do you think slight smearing in 25 secs given that rough setup is reasonable or should it be better?
Thanks, Rick


Re: Mount coordinates change while autoguiding

Roland Christen
 


Back in RAPAS, Polaris was noticeably out of place.
Yes, and then you adjust the RAPAS via the 3 collimation screws to put Polaris where it should be, and then you have a RAPAS that can recreate that perfect polar alignment in about 10 seconds next time you set up. That's the whole idea about the collimation screws on the RAPAS.

Rolando


-----Original Message-----
From: Michael Dolenga via groups.io <giroditalia@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 21, 2020 1:44 pm
Subject: Re: [ap-gto] Mount coordinates change while autoguiding

I got the Polemaster camera, and used it with SharpCap. After careful alignment with the RAPAS, sharpcap reported an error of about 5 arcminutes, which it categorizes as "poor." A few minutes with the app and it was down to 11 arc seconds error. Back in RAPAS, Polaris was noticeably out of place. The imaging session I did last night showed at most 5 arc seconds of drift per hour over a 4 hour period, so clearly there was an improvement, although that's anecdotal at best. And I don't see any improvement on the images, I think we're seeing limited here in Seattle. Actually, cloud limited. :)

Michael



On Saturday, July 18, 2020, 09:39:18 AM PDT, uncarollo2 <chris1011@...> wrote:



Btw, is a 1 minute DEC drift over 1 hour at a declination of about 40 degrees good/bad?
The mount itself doesn't move in Dec, so all drift is due to external errors (atmospheric refraction, differential flexure, polar misalignment). Most Dec drift is simple polar misalignment in azimuth when pointing overhead and altitude misalignment when pointing towards the east or west.

Is 1 minute drift good/bad - I think that's bordering on excessive and can be easily fixed using PEMPro drift alignment. Good alignment back in the "good ol' days" was 1 arc sec drift per 5 minutes. That's back in my day when we used to walk uphill to school thru 5 foot snow drifts, and uphill again home.

Rolando


-----Original Message-----
From: Michael Dolenga via groups.io <giroditalia@...>
To: main@ap-gto.groups.io
Sent: Sat, Jul 18, 2020 11:27 am
Subject: Re: [ap-gto] Mount coordinates change while autoguiding

You do need to recalibrate after flipping to account for orthogonality errors. And you'd have to slew to the same coordinates reported by the mount just before you flip, which differ from the target. It's not really an issue once you understand what is happening, and luckily the software I'm using, NINA, does a plate solve after flipping and re-slews, if necessary, to your original target coordinates which it has preserved. I raise the question because until I understood how NINA worked, I thought the drift on the mount was problematic.

When I was doing flips manually, I would calibrate before flipping to reset the mount's coordinates to match my target, as Ray suggested.

Btw, is a 1 minute DEC drift over 1 hour at a declination of about 40 degrees good/bad? 1850 mm scope. Polar aligned using RAPAS.


Michael



On Saturday, July 18, 2020, 09:06:43 AM PDT, uncarollo2 <chris1011@...> via groups.io <chris1011@...> wrote:



The meridian flip automation i use includes a re-centering of the target via plate solve, which I think is pretty common
When you are autoguiding the target is always centered so no plate solve is needed. Because of the guide commands, the internal co-ordinates slowly drift, so at the end of the session you simply do a recal which brings the actual and commanded co-ordinates back together.

Rolando


-----Original Message-----
From: Brian Valente <bvalente@...>
To: main@ap-gto.groups.io
Sent: Sat, Jul 18, 2020 10:52 am
Subject: Re: [ap-gto] Mount coordinates change while autoguiding

>>> If I leave the mount running with no autoguider connected at all, RA and DEC remain constant, as I would expect. 

But likely the fov would have change significantly, so your target would have drifted out of frame

 >>>This confounds automated meridian flips because the mount "thinks" it is pointed somewhere other than where it actually is. Often, the difference is too slight to be significance, but sometimes not. 

The meridian flip automation i use includes a re-centering of the target via plate solve, which I think is pretty common


Brian


On Sat, Jul 18, 2020 at 8:48 AM uncarollo2 <chris1011@...> via groups.io <chris1011=aol.com@groups.io> wrote:

It seems as though the autoguider commands are being interpreted as user initiated slews.
Yes, autoguider commands are essentially user initiated moves which cause the mount to go to a new coordinate every time a move command is issued. This is universal and applies to every mount ever made, whether AP mount or other brands. They will all do the same.

Rolando


-----Original Message-----
From: Michael Dolenga via groups.io <giroditalia=yahoo.com@groups.io>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Sat, Jul 18, 2020 9:31 am
Subject: [ap-gto] Mount coordinates change while autoguiding

I've noticed that my 900GTO's coordinates, as reported by ASCOM (latest version of the driver) change over a session where I am autoguiding. This occurs whether using MaximDL or NINA/PhD. In both cases, I am configured to send autoguider commands via the ASCOM driver rather than a separate ST4 cable.

This confounds automated meridian flips because the mount "thinks" it is pointed somewhere other than where it actually is. Often, the difference is too slight to be significance, but sometimes not. 

As an example, last night I was doing 30 minute shots of the Crescent Nebula. Over one hour, as reported by the RA/DEC fields written into the FITS header, I saw a difference of 6 minutes, 4 seconds in RA and 1 minute 7 seconds in DEC.

If I leave the mount running with no autoguider connected at all, RA and DEC remain constant, as I would expect.

Is this expected behavior or am I possibly missing some configuration option? It seems as though the autoguider commands are being interpreted as user initiated slews.


Michael


--
Brian 



Brian Valente


Re: NGC6960

Stuart <stuart.j.heggie@...>
 

Nice work Mike! Big target - you did well to squeeze it in!


On Tue, 21 Jul 2020 at 13:45, Mike Dodd <mike@...> wrote:
I've long been attracted to the Veil Nebula, but never could image
NGC6960, The Witch's Broom, because my old ST-8 CCD camera bloomed the
bright star. But my current ASI1600MCP one-shot color CMOS camera
doesn't bloom, so now this target is in play.

Recently I managed to acquire nearly 5 hours of data over three rare
clear nights, and hope to get another 3-4 hours when the sky clears
again. Here's what I have so far:
<http://astronomy.mdodd.com/nebulae-17.html>

I rotated the camera to capture as much of the "broom" as possible on
the sensor, corner-to-corner. I never knew there was so much faint H-a
nebulosity close-by. Maybe additional data will reveal more.

Comments and suggestions welcome.

TMB-130SS APO @ f/7 on an AP1200.

--- Mike
http://astronomy.mdodd.com





--

Stuart
http://www.astrofoto.ca/stuartheggie/

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