Last night tracking with Mach2


Roland Christen
 

Hi Astronuts,

I was busy yesterday testing mount software in our AP observatory. After dusk I noticed the sky was very dark - very low humidity, and good seeing. So I captured a number of unguided images of the Ring Nebula just for fun. 160 EDF refractor on the Mach2. Below is what I consider a successful imaging session.

For those needing an explanation of the pix below, I modeled a path for the object by measuring the position of 4 stars along the path. Took about 1 - 2 minutes per star to center them and add it to the model in the CP controller. The image shows how the RA axis moved over a 1 hour time period, starting when the object was approximately 3 hours from the meridian. This motion of the RA axis is a very close match to how the object actually moved across the sky. The difference or error in that 1 hour exposure was approximately 2 pixels. I took a number of 600 second exposures during that time with results as you can see in the image below.

What would have been the difference between modeled tracking with the Mach2 versus guiding? The main difference is in the smoothness of the tracking. Guiding would almost always impart a back and forth sawtooth motion, which can be very small on a premium mount, but can be several arc sec P-P on a lesser one. With fast optics and modern astrocameras, it's getting so that 10 minute exposures are plenty for even the faintest stuff. And for that you can model with a minimum of points along the object path.

Rolando


Dean Jacobsen
 

Roland, you are doing this modeled tracking with the keypad application, right?

So if the path of my object will cause my scope to hit my pier a half an hour or an hour after the meridian, I could set up a modeled tracking run up to and maybe slightly past the meridian, then when the mount tracks across the meridian I could take a few more minutes and set up another run for the object's movement into the west.  Correct? 
--
Dean Jacobsen
http://astrophoto.net/wp/ 
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


 

Is the Astro-Physics PEC Processor an "in-house" only application?


Roland Christen
 


then when the mount tracks across the meridian I could take a few more minutes and set up another run for the object's movement into the west.  Correct? 
--
You can set up the model ahead of time, during twilight, and do it on both sides of the mount. I set up my model 2 hours before sunset using Ha filter on my camera with exposures of .03 seconds. I could easily capture stars down to mag4.5. I would not take up precious clear sky imaging time to establish a model at night.

Roland


-----Original Message-----
From: Dean Jacobsen <deanjacobsen@...>
To: main@ap-gto.groups.io
Sent: Fri, Jun 12, 2020 1:55 pm
Subject: Re: [ap-gto] Last night tracking with Mach2

Roland, you are doing this modeled tracking with the keypad application, right?

So if the path of my object will cause my scope to hit my pier a half an hour or an hour after the meridian, I could set up a modeled tracking run up to and maybe slightly past the meridian, then when the mount tracks across the meridian I could take a few more minutes and set up another run for the object's movement into the west.  Correct? 
--
Dean Jacobsen
http://astrophoto.net/wp/ 
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Roland Christen
 


Is the Astro-Physics PEC Processor an "in-house" only application?
Yes, we use it for multiple test and setup sequences on our encoder mounts.

Rolando


-----Original Message-----
From: Jerome Allison <jallison@...>
To: main@ap-gto.groups.io
Sent: Fri, Jun 12, 2020 3:24 pm
Subject: Re: [ap-gto] Last night tracking with Mach2

Is the Astro-Physics PEC Processor an "in-house" only application?


Dean Jacobsen
 

So the model is still valid after a meridian flip?
--
Dean Jacobsen
http://astrophoto.net/wp/ 
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Terri Zittritsch
 

On Fri, Jun 12, 2020 at 08:46 PM, uncarollo2 <chris1011@...> wrote:
You can set up the model ahead of time, during twilight, and do it on both sides of the mount. I set up my model 2 hours before sunset using Ha filter on my camera with exposures of .03 seconds. I could easily capture stars down to mag4.5. I would not take up precious clear sky imaging time to establish a model at night.
 
Roland
I think what you're explaining is your new hand controller SW for the mach2, can you say when it might be available?    I'd like to be able to use the hand controller at some point, even if it doesn't have all of the fancy features enabled yet.   Right now, always teathered to my PC.  I don't want it before it's ready, but is there some outlook?


Thanks,
Terri


Tony Benjamin <tonybenjamin@...>
 

So can anyone do this with just a mount and APPM? Using a Ha filter 2 hrs before sunset at .03sec exposure and build a model????

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Terri Zittritsch
Sent: June 13, 2020 6:55 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Last night tracking with Mach2

 

On Fri, Jun 12, 2020 at 08:46 PM, uncarollo2 <chris1011@...> wrote:

You can set up the model ahead of time, during twilight, and do it on both sides of the mount. I set up my model 2 hours before sunset using Ha filter on my camera with exposures of .03 seconds. I could easily capture stars down to mag4.5. I would not take up precious clear sky imaging time to establish a model at night.

 

Roland

I think what you're explaining is your new hand controller SW for the mach2, can you say when it might be available?    I'd like to be able to use the hand controller at some point, even if it doesn't have all of the fancy features enabled yet.   Right now, always teathered to my PC.  I don't want it before it's ready, but is there some outlook?


Thanks,
Terri


Dominique Durand
 
Edited

On Sat, Jun 13, 2020 at 03:55 PM, Terri Zittritsch wrote:
I think what you're explaining is your new hand controller SW for the mach2, can you say when it might be available?    I'd like to be able to use the hand controller at some point, even if it doesn't have all of the fancy features enabled yet.   Right now, always teathered to my PC.  I don't want it before it's ready, but is there some outlook?
Me too, I would like to be able to have it, even if with the PC it goes perfectly well, because once the model is done it rolls by itself.His arrival with my stowaway's 92TCC will make him happy.

And congratulations Rolando, because new demonstration that with this frame we can put guide glasses, optical dividers, guide cameras and other PHD2 in the closet, with or without keypad.


Roland Christen
 


So the model is still valid after a meridian flip?
Each side has its own model. You make a model for one side, then you make a model for the other side. You do this before it gets dark. When you are actually imaging, the models will be applied according to which side you are on. If you never move the mount (i.e. permanent setup) then the model will be good essentially forever. I made a model a week ago, I used it every clear night after that and it worked the same every night.

Rolando


-----Original Message-----
From: Dean Jacobsen <deanjacobsen@...>
To: main@ap-gto.groups.io
Sent: Sat, Jun 13, 2020 3:07 am
Subject: Re: [ap-gto] Last night tracking with Mach2

So the model is still valid after a meridian flip?
--
Dean Jacobsen
http://astrophoto.net/wp/ 
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Roland Christen
 

We are working on the instruction manual as I type. Without this it may e difficult to operate all the new features.

I'm as anxious as you are to get this part of the project done. You will be asked to be one of the first beta testers, since you have the keypad. You will need to download the latest software both for your mount and for the keypad since we made some changes in both.

Rolando



-----Original Message-----
From: Terri Zittritsch <theresamarie11@...>
To: main@ap-gto.groups.io
Sent: Sat, Jun 13, 2020 8:55 am
Subject: Re: [ap-gto] Last night tracking with Mach2

On Fri, Jun 12, 2020 at 08:46 PM, uncarollo2 <chris1011@...> wrote:
You can set up the model ahead of time, during twilight, and do it on both sides of the mount. I set up my model 2 hours before sunset using Ha filter on my camera with exposures of .03 seconds. I could easily capture stars down to mag4.5. I would not take up precious clear sky imaging time to establish a model at night.
 
Roland
I think what you're explaining is your new hand controller SW for the mach2, can you say when it might be available?    I'd like to be able to use the hand controller at some point, even if it doesn't have all of the fancy features enabled yet.   Right now, always teathered to my PC.  I don't want it before it's ready, but is there some outlook?


Thanks,
Terri


Roland Christen
 

APPM works differently - it does not use bright stars, just star fields. You need dark skies for that to do plate solves. In my keypad routine you send the mount to known stars using a planetarium program. Completely different way of doing a model.

Rolando



-----Original Message-----
From: Tony Benjamin <tonybenjamin@...>
To: main@ap-gto.groups.io
Sent: Sat, Jun 13, 2020 9:31 am
Subject: Re: [ap-gto] Last night tracking with Mach2

So can anyone do this with just a mount and APPM? Using a Ha filter 2 hrs before sunset at .03sec exposure and build a model????
 
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Terri Zittritsch
Sent: June 13, 2020 6:55 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Last night tracking with Mach2
 
On Fri, Jun 12, 2020 at 08:46 PM, uncarollo2 <chris1011@...> wrote:
You can set up the model ahead of time, during twilight, and do it on both sides of the mount. I set up my model 2 hours before sunset using Ha filter on my camera with exposures of .03 seconds. I could easily capture stars down to mag4.5. I would not take up precious clear sky imaging time to establish a model at night.
 
Roland
I think what you're explaining is your new hand controller SW for the mach2, can you say when it might be available?    I'd like to be able to use the hand controller at some point, even if it doesn't have all of the fancy features enabled yet.   Right now, always teathered to my PC.  I don't want it before it's ready, but is there some outlook?


Thanks,
Terri


Dean Jacobsen
 
Edited

OK, got it.  


BTW, did my first APPM mapping run last night and activated tracking rate correction for the first time with the Mach2.  (Third use of the mount under the stars. ) Got a series of 56 x 4 min. unguided narrowband exposures over 3.7 hours.  The modeling - 68 points or so - took a half an hour while it was getting dark, the sky was settling down and the optics were cooling down.  

It worked wonderfully.  Used all 56 frames in the integration stack.

I am very impressed with the mount and the software.  
--
Dean Jacobsen
http://astrophoto.net/wp/ 
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Terri Zittritsch
 

Rolando, thank you for the update.   There's been a couple of times now where I just wanted to roll the scope out during the day to use it for solar viewing, but didn't because i didn't want to get the table, chairs, etc, etc..
Looking forward to helping you test.

Terri


On Sat, Jun 13, 2020 at 01:53 PM, uncarollo2 <chris1011@...> wrote:
We are working on the instruction manual as I type. Without this it may e difficult to operate all the new features.
 
I'm as anxious as you are to get this part of the project done. You will be asked to be one of the first beta testers, since you have the keypad. You will need to download the latest software both for your mount and for the keypad since we made some changes in both.
 
Rolando
 


Worsel
 

Tony

AFAIK, it is a bit more complex.  For a non-AE, non-HC mount, you also need one of the imaging apps and one of the plate-solving apps listed in Section 15 of https://www.astro-physics.info/tech_support/software/apcc/apcc-pro.pdf


Bryan


Worsel
 

Roland

A creative approach!  What scope were you using for this...17.5 or 130 or ??

Bryan

----
You can set up the model ahead of time, during twilight, and do it on both sides of the mount. I set up my model 2 hours before sunset using Ha filter on my camera with exposures of .03 seconds. I could easily capture stars down to mag4.5. I would not take up precious clear sky imaging time to establish a model at night.
 
Roland
----