New Video: PHD2 with Encoder Mounts


Karen Christen
 

Hey Astro-Nuts,

 

We have another new video to share with you!  If you’re using PHD2 for guiding with an AP encoder mount (Mach2GTO, 1100GTO-AE or 1600GTO-AE), this is for you. This tutorial covers basic PHD2 settings, how to properly calibrate your guiding, and how to tune your parameters using the Guiding Assistant.  Check it out here: https://www.youtube.com/watch?v=wCu8PKjDZ20  Consider subscribing to the AP YouTube channel to be informed of all new videos as they’re posted. 

 

A big thanks to Brian Valente for working with Bruce from PHD2 and creating this informative tutorial! 

Karen

AP


--
Karen Christen
Astro-Physics


Keith Olsen
 

These videos are very helpful, I look forward for more to come.  Thanks for all the work.

Keith


midmoastro
 

Thank you, Karen.
I've been using my Mach2 without guiding, shooting around 488 to 800mm focal length.
I noticed for this tutorial the focal length was quite long so I unnderstand the benefits it can provide. Does PHD2 guiding with an encoder mount offer any benefit for those shooting under 1000mm FL?
I am in Missouri so my nights of excellent seeing are very minimal and I was thinking the additional setup and guiding may not offer me much, especially with mediocre seeing. I'm curious if anyone has tested this and found benefits?
Thank you again for all of these great videos.
Todd


Dean Jacobsen
 

On Sat, May 7, 2022 at 06:24 AM, midmoastro wrote:
I've been using my Mach2 without guiding, shooting around 488 to 800mm focal length.
I noticed for this tutorial the focal length was quite long so I unnderstand the benefits it can provide. Does PHD2 guiding with an encoder mount offer any benefit for those shooting under 1000mm FL?
I am in Missouri so my nights of excellent seeing are very minimal and I was thinking the additional setup and guiding may not offer me much, especially with mediocre seeing. I'm curious if anyone has tested this and found benefits?
Hi Todd, this would be a great subject for a new thread.  I would be interested in reading about the experiences of other encoder mount owners in response to your questions.
 
--
Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/


 

Hi Todd

I think about your question slightly differently: 

To me, guiding is a last resort. It adds complexity and additional points of potential failure (no guidestar, lost guidestar, another camera to worry about ;) )

It really boils down to whether you are happy with your images. If you are, I'd skip guiding.

 If you aren't happy and it's due to tracking, I would first look at improving polar alignment, then look at adding sky modeling (all sky or dec arc), and then if that still isn't enough then consider adding guiding. 

The same long focal length setup used in the demonstration also has an 80mm piggyback refractor @ 480mm, and I use it unguided even though guiding is available. 

I hope this doesn't come across as anti-guiding: in the right situations it's critical. But there are many excellent tools an AP encoder mount provides you with to help here

hth

Brian


On Sat, May 7, 2022 at 6:24 AM midmoastro <teche70@...> wrote:
Thank you, Karen.
I've been using my Mach2 without guiding, shooting around 488 to 800mm focal length.
I noticed for this tutorial the focal length was quite long so I unnderstand the benefits it can provide. Does PHD2 guiding with an encoder mount offer any benefit for those shooting under 1000mm FL?
I am in Missouri so my nights of excellent seeing are very minimal and I was thinking the additional setup and guiding may not offer me much, especially with mediocre seeing. I'm curious if anyone has tested this and found benefits?
Thank you again for all of these great videos.
Todd




Dean Jacobsen
 

That was a well done video.  The new endocder-mount-specific features look great.
--
Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/


Cheng-Yang Tan
 

Very nice! I've set the PHD2 parameters the same as the video for my AP1100AE. And thanks to this video, I now know that PHD2 requires the arcsec/pixel to be >= 0.5. 

Thanks!

cytan

On Friday, May 6, 2022, 08:27:23 PM CDT, Karen Christen <karen@...> wrote:


Hey Astro-Nuts,

 

We have another new video to share with you!  If you’re using PHD2 for guiding with an AP encoder mount (Mach2GTO, 1100GTO-AE or 1600GTO-AE), this is for you. This tutorial covers basic PHD2 settings, how to properly calibrate your guiding, and how to tune your parameters using the Guiding Assistant.  Check it out here: https://www.youtube.com/watch?v=wCu8PKjDZ20  Consider subscribing to the AP YouTube channel to be informed of all new videos as they’re posted. 

 

A big thanks to Brian Valente for working with Bruce from PHD2 and creating this informative tutorial! 

Karen

AP


--
Karen Christen
Astro-Physics


 

Thanks for pointing that out cytan, that's not something that is well known

Another takeaway for encoder mount owners, these new features were just released with 2.6.11dev1 release and previously weren't available. Bruce Waddington worked with a number of AP owners to help test and tune these capabilities. 





On Sat, May 7, 2022 at 9:33 AM Cheng-Yang Tan via groups.io <cytan299=yahoo.com@groups.io> wrote:
Very nice! I've set the PHD2 parameters the same as the video for my AP1100AE. And thanks to this video, I now know that PHD2 requires the arcsec/pixel to be >= 0.5. 

Thanks!

cytan

On Friday, May 6, 2022, 08:27:23 PM CDT, Karen Christen <karen@...> wrote:


Hey Astro-Nuts,

 

We have another new video to share with you!  If you’re using PHD2 for guiding with an AP encoder mount (Mach2GTO, 1100GTO-AE or 1600GTO-AE), this is for you. This tutorial covers basic PHD2 settings, how to properly calibrate your guiding, and how to tune your parameters using the Guiding Assistant.  Check it out here: https://www.youtube.com/watch?v=wCu8PKjDZ20  Consider subscribing to the AP YouTube channel to be informed of all new videos as they’re posted. 

 

A big thanks to Brian Valente for working with Bruce from PHD2 and creating this informative tutorial! 

Karen

AP


--
Karen Christen
Astro-Physics




Tom Zepf
 

I happened upon the new features in the wizard after installing 2.6.11dev1 and this provided a very clear explanation of the new features.

Thanks for the great video!

   Tom


Chris White
 

Nice Job Brian!  Thanks for the video AP!  Will come in handy for my future M2. 


ap@CaptivePhotons.com
 

On Sat, May 7, 2022 at 12:33 PM, Cheng-Yang Tan wrote:
Very nice! I've set the PHD2 parameters the same as the video for my AP1100AE. And thanks to this video, I now know that PHD2 requires the arcsec/pixel to be >= 0.5. 
 
On Sat, May 7, 2022 at 12:36 PM, Brian Valente wrote:
Thanks for pointing that out cytan, that's not something that is well known

I did not realize that either.  How does one evaluate the upper bound?  I image typically at 0.28"/px, and the guide via the OAG is at 0.43"/px now.  To bin I go up to 0.9"/px.  My typical guiding is in the low 0.20's if the seeing is good, so it seems a bit counter-intuitive to raise my guide scale upo near 0.9". 

I can obviously if that's better.  Does the normal guiding play a role in that 0.5"/px guidance? 

And yes, thanks for the video.  Because these darn AP Encoder mounts just work well pretty much no matter how I screw around with PHD2, it is hard to tell what works best and not as good.  I do really like the variable delay however, it makes the normally inefficient settle times much more brief!

Linwood


 

Hi Linwood

>>>How does one evaluate the upper bound? 

First the lower bound is a little more solid than a general suggestion because the math for centroid calculation is best at 0.5" or above. 0.43" is pretty close. 

Regarding the upper bound, the evaluation is your guiding RMS in arcseconds and whether that is acceptable for your imaging pixel scale.

The general recommendation for the ratio of guidescope pixel scale to imaging pixel scale should be no more than 4:1 (personally I stick with 3:1). You are kind of in that area whether you are guiding binned or unbinned. 

0.43" is close to 0.5" so it may be okay. For your situation I'd say experimentation and comparing results would tell the tale. I suspect binned or unbinned in your situation would probably yield similar results, especially if you are using the longish guide exposures. 

Like everything astro, the most important measure is your results. Whatever you are doing for your best guiding, I would go with that. 

Brian


On Sun, May 8, 2022 at 5:17 PM ap@... <ap@...> wrote:
On Sat, May 7, 2022 at 12:33 PM, Cheng-Yang Tan wrote:
Very nice! I've set the PHD2 parameters the same as the video for my AP1100AE. And thanks to this video, I now know that PHD2 requires the arcsec/pixel to be >= 0.5. 
 
On Sat, May 7, 2022 at 12:36 PM, Brian Valente wrote:
Thanks for pointing that out cytan, that's not something that is well known

I did not realize that either.  How does one evaluate the upper bound?  I image typically at 0.28"/px, and the guide via the OAG is at 0.43"/px now.  To bin I go up to 0.9"/px.  My typical guiding is in the low 0.20's if the seeing is good, so it seems a bit counter-intuitive to raise my guide scale upo near 0.9". 

I can obviously if that's better.  Does the normal guiding play a role in that 0.5"/px guidance? 

And yes, thanks for the video.  Because these darn AP Encoder mounts just work well pretty much no matter how I screw around with PHD2, it is hard to tell what works best and not as good.  I do really like the variable delay however, it makes the normally inefficient settle times much more brief!

Linwood




ap@CaptivePhotons.com
 

On Sun, May 8, 2022 at 10:19 PM, Brian Valente wrote:
0.43" is close to 0.5" so it may be okay. For your situation I'd say experimentation and comparing results would tell the tale. I suspect binned or unbinned in your situation would probably yield similar results, especially if you are using the longish guide exposures. 
The target I wanted tonight (M13) rose a bit late, so I did some experimentation before hand, and I think that sums it up -- it just didn't seem to make any difference.  Though this was with a C11 with dew shield and wind 5 gusting to 10 mph, so there is quite a bit of "noise" in my experiment.

But I ended up leaving it bin 2, since that probably saves a fraction of a second on downloads. 

I will try again some night when the wind is more calm and guiding details might actually show up rather than being lost in the noise.

Thanks for the feedback.  And the video. 

Linwood