Date   

Dew cap internal flocking peeling off

Jim Fakatselis
 

The black flocking lining on my 130EDF dew cap has peeled off.  Any ideas on how to repair it?
Thank you in advance.  

Jim


Re: Spikes in DEC #guiding #Guiding

 

Hi Sebastian

I meant things exactly like what Roland said - he suggested it was DEC imbalance.

On Mon, May 3, 2021 at 11:43 AM Seb@stro <sebastiendore1@...> wrote:
Hi Brian,

encoder mounts like the Mach 2 require some basic correct setup, and i'm not sure yours is there

Just re-reading your comment above and  I'm not sure I clearly understand what you mean by "basic correct setup". Are suggesting I should refine some settings within the imaging/guiding softwares ? Or are you saying I should look into the mechanical aspect of the OTA, OAG, camera, etc. ?

I just saw Howard and Roland also replied, so I will follow-up with them as well. 

I must add I am not just blown away by the mount's performance which, as you pointed out, is very good at < 0.5", but also by AP's ***** (five stars) customer service. A flawless customer experience...

Sebastien


De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Brian Valente <bvalente@...>
Envoyé : 3 mai 2021 03:00
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] Spikes in DEC #guiding #guiding
 
HI Sebastian

I suggest you take this up with AP in their forums

encoder mounts like the Mach 2 require some basic correct setup, and i'm not sure yours is there (i'm not suggesting there's anything wrong with the mount at all: you are guiding < 0.50")

 looking at a typical run, your DEC is odd for the following reasons: 
- those excursions are not the result of any PHD type of correction
- all your corrections are in one direction both RA and DEC, and corrections exhibit a clumping 

this is dec showing the large instantaneous jumps and guiding in only one direction 
image.png

image.png

I suggest you do a guiding assistant run for a few minutes to measure polar misalignment. it could be something is terribly off on polar align, but based on what you're saying i don't know. 



On Sun, May 2, 2021 at 10:29 PM Seb@stro <sebastiendore1@...> wrote:
Hi Brian,

Thanks for your reply.  Logs here: https://openphdguiding.org/logs/dl/PHD2_logs_BqZp.zip

I should probably have added that my imaging scale is 1.04"/px. So it's probably impacting a bit, maybe not much... But to be honest my concern was also about the working order the mount.  

But don't get me wrong, I'm coming from a low budget asian mount and got the Mach2 about 2 months ago. It performs WAAAAAAAAYYYYYYYYYYYYYYY better, no question there. So there's the fact that I'm not very familiar with AP mounts limits regarding tracking and guiding yet. Had a handful of clear nights only. And I know my system is the challenging kind (mirrors, long FL, reducer backfocus, etc.)... So I just thought I'd ask for educated guess here.

Might also be PA as you pointed out. But I thought I did well since I polar aligned with RAPAS at the beginning of my session and refined with PHD2 polar drift align afterward. When I ran the Guiding assistant, I recall it was saying it was around 2-3 arcmin from the NCP... Do you think it's reasonable for my imaging scale (1"/px) ?

Sebastien


De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Brian Valente <bvalente@...>
Envoyé : 3 mai 2021 00:48
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] Spikes in DEC #guiding #guiding
 
Hi  Sebastien

Please upload your guidelogs for this https://openphdguiding.org/getting-help/ 


Screen caps aren't enough information, but a quick glance looks like you have pretty bad polar alignment which would dramatically impact your DEC guiding

guidelogs would tell more


I wonder how much of an issue guiding is here - your overall rms is 0.49" and your image scale is 1.7"/pix, i'm guessing even if you addressed this you may not see a difference in your images


Brian
 

On Sun, May 2, 2021 at 9:44 PM Seb@stro <sebastiendore1@...> wrote:
Hello all, 

I'm having some spikes in my DEC guiding at times tonight. The worst ones seem to occur at periodic interval around 20-25 seconds but not all the time. Like about a dozen times in 400s periods. RMS values are good but DEC is about 40% bigger than RA because of these excursions. 

Conditions are fairly good now. No wind at all. Balance was quite accurate (as far as my eye can tell) in both RA and DEC. PA error reported by PHD2 is below 5 arc-min. I have a NUC on top of OTA, so no cable snag possible. Seeing is fair at 3.5-4".

My setup:
-EdgeHD 800 reduced to 1400mm FL
-Guide cam pixel scale : 1.7"/px
-Guiding through OAG at 3-4 seconds interval

Imaging M106 which is about 2hrs past meridian at the time of writing this.

That said, I'm not that familiar with guiding at such focal length... Any thoughts on what might be causing this ?

Sebastien



--
Brian 



Brian Valente



--
Brian 



Brian Valente



--
Brian 



Brian Valente


Re: 1100GTO case

M Hambrick
 

Hi Todd

Have you watched Tony's (a.k.a Harley Davidson) YouTube video showing the Ridgid toolboxes ? I copied the link below. I am using the same cases for my 1100, and I have lined mine with high density closed cell foam. I needed four cases to hold all of the 1100 components; the Dec axis with saddle plate attached sits in the wheeled case. The RA axis sits in the 22-inch box, and the counterweight shaft and counterweights sit in two of the narrow boxes. All will stack on top of the wheeled box. There is room in the Dec axis case for the GTOCP4, Keypad, and cables.

The Ridgid cases are pretty tough, but I would not recommend them for airline travel. If you are looking for cases suitable for airline travel you probably want to go with a Pelican case, or if they are still in business get some custom cases from Company 7. Their cases look really good but expensive.

You can find the 1.8 density closed cell polyethylene foam on Amazon or eBay. 

I hope this helps.

Mike

ASTRO PHYSICS 1100GTO mount - cases I use for transport - YouTube




Re: Spikes in DEC #guiding #Guiding

Seb@stro
 

Hi Brian,

encoder mounts like the Mach 2 require some basic correct setup, and i'm not sure yours is there

Just re-reading your comment above and  I'm not sure I clearly understand what you mean by "basic correct setup". Are suggesting I should refine some settings within the imaging/guiding softwares ? Or are you saying I should look into the mechanical aspect of the OTA, OAG, camera, etc. ?

I just saw Howard and Roland also replied, so I will follow-up with them as well. 

I must add I am not just blown away by the mount's performance which, as you pointed out, is very good at < 0.5", but also by AP's ***** (five stars) customer service. A flawless customer experience...

Sebastien


De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Brian Valente <bvalente@...>
Envoyé : 3 mai 2021 03:00
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] Spikes in DEC #guiding #guiding
 
HI Sebastian

I suggest you take this up with AP in their forums

encoder mounts like the Mach 2 require some basic correct setup, and i'm not sure yours is there (i'm not suggesting there's anything wrong with the mount at all: you are guiding < 0.50")

 looking at a typical run, your DEC is odd for the following reasons: 
- those excursions are not the result of any PHD type of correction
- all your corrections are in one direction both RA and DEC, and corrections exhibit a clumping 

this is dec showing the large instantaneous jumps and guiding in only one direction 
image.png

image.png

I suggest you do a guiding assistant run for a few minutes to measure polar misalignment. it could be something is terribly off on polar align, but based on what you're saying i don't know. 



On Sun, May 2, 2021 at 10:29 PM Seb@stro <sebastiendore1@...> wrote:
Hi Brian,

Thanks for your reply.  Logs here: https://openphdguiding.org/logs/dl/PHD2_logs_BqZp.zip

I should probably have added that my imaging scale is 1.04"/px. So it's probably impacting a bit, maybe not much... But to be honest my concern was also about the working order the mount.  

But don't get me wrong, I'm coming from a low budget asian mount and got the Mach2 about 2 months ago. It performs WAAAAAAAAYYYYYYYYYYYYYYY better, no question there. So there's the fact that I'm not very familiar with AP mounts limits regarding tracking and guiding yet. Had a handful of clear nights only. And I know my system is the challenging kind (mirrors, long FL, reducer backfocus, etc.)... So I just thought I'd ask for educated guess here.

Might also be PA as you pointed out. But I thought I did well since I polar aligned with RAPAS at the beginning of my session and refined with PHD2 polar drift align afterward. When I ran the Guiding assistant, I recall it was saying it was around 2-3 arcmin from the NCP... Do you think it's reasonable for my imaging scale (1"/px) ?

Sebastien


De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Brian Valente <bvalente@...>
Envoyé : 3 mai 2021 00:48
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] Spikes in DEC #guiding #guiding
 
Hi  Sebastien

Please upload your guidelogs for this https://openphdguiding.org/getting-help/ 


Screen caps aren't enough information, but a quick glance looks like you have pretty bad polar alignment which would dramatically impact your DEC guiding

guidelogs would tell more


I wonder how much of an issue guiding is here - your overall rms is 0.49" and your image scale is 1.7"/pix, i'm guessing even if you addressed this you may not see a difference in your images


Brian
 

On Sun, May 2, 2021 at 9:44 PM Seb@stro <sebastiendore1@...> wrote:
Hello all, 

I'm having some spikes in my DEC guiding at times tonight. The worst ones seem to occur at periodic interval around 20-25 seconds but not all the time. Like about a dozen times in 400s periods. RMS values are good but DEC is about 40% bigger than RA because of these excursions. 

Conditions are fairly good now. No wind at all. Balance was quite accurate (as far as my eye can tell) in both RA and DEC. PA error reported by PHD2 is below 5 arc-min. I have a NUC on top of OTA, so no cable snag possible. Seeing is fair at 3.5-4".

My setup:
-EdgeHD 800 reduced to 1400mm FL
-Guide cam pixel scale : 1.7"/px
-Guiding through OAG at 3-4 seconds interval

Imaging M106 which is about 2hrs past meridian at the time of writing this.

That said, I'm not that familiar with guiding at such focal length... Any thoughts on what might be causing this ?

Sebastien



--
Brian 



Brian Valente



--
Brian 



Brian Valente


Re: Spikes in DEC #Guiding

Roland Christen
 

This indicates a severe unbalance in Dec which puts a lot of pressure on the gear teeth and causes high friction.

Check your Dec balance by sending the mount to Park1 or 4 or 5 and loosening all 4 clutch knobs fully. You must be well balanced in Dec, especially if your load is heavy. With clutches loose, feel the weight as you move the scope back and forth.

Roland


-----Original Message-----
From: Seb@stro <sebastiendore1@...>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Mon, May 3, 2021 12:59 am
Subject: Re: [ap-gto] Spikes in DEC #guiding #guiding

I seem to have some very consistant spikes (about 3" in magnitude) every 130 seconds now. I have monitored for about 20 minutes long and they are very predictable... Note that I have reduced exposure time to 2.0s, just to see if I would see more spikes when sampling faster.



--
Roland Christen
Astro-Physics


1100GTO case

midmoastro
 

I searched through some older threads but thought I would make this one more specific, and updated, as the last one was several years old.
I would like to purchase two separate travel cases for the 1100 RA/DEC. Is anyone using Pelican cases, or similar, for transportation of their 1100? I would love to see some pictures if possible. Sturdy foam is necessary too. I think four cases will cover my needs with the third for CW shaft and weights and the fourth for the keypad, GTOCP4, and accessories but I would really like to see what others are using.

By the way, when I received my mount several weeks ago I had two days of clear skies. Despite that, I patiently waited and practiced set up and tear down. Then clouds moved in over the next several days so I got the CP4 connected to WiFi, tested connection via USB, connected with SkySafari, etc. Later I got APCC downloaded and set up on my Windows 10 VM on my Mac so that was working. Finally this past weekend I got outside and used RAPAS to polar align, then I checked it with SharpCap polar align as I still need to adjust the RAPAS. Fired up APCC, PHD2, and ran some calibration and I was ready. I got 90 minutes of data on M81 and M82 and tracking was beautiful. Everything worked great. Thanks to all at Astro-Physics, the mount is beautiful and working great. The weight of each piece is very manageable for me and set up and tear down is really quick. 
Todd


Re: AP1200 GTO chatter

Don Anderson
 

Mike
Dale provided a good explanation to your questions. I would add though that the different sounds you hear running the mount in the reverse direction is the result of the gears pulling on the back side of the gear teeth. The two sides of the gear teeth can have slightly different surface finishes from each other which can generate different sounds depending on which side the load is putting pressure on. This can become more apparent as the gears wear in with use. This is especially true for the RA axis which is normally running in one direction only.
In any case don't worry about it. It is simply your gear trains personality!
Regards

Don Anderson


On Monday, May 3, 2021, 10:26:02 a.m. MDT, Mike C <mike@...> wrote:


I finally removed my DEC gearbox on my AP1200. I haven't done the RA yet. The mount has been getting a bit louder with each passing Winter and started really talking this last WInter on the first slews of the evening. I removed all the old grease and got the worm and wheel quite shiny. I applied the new grease from the AP kit.

Afterwards, inside at least, the DEC operation is quieter than I remember in a long time. 

Questions -

1) I marked the spur gears with pencil but the pencil marks were lost on the plastic gear when cleaning.  So.. I hope that original orientation isn't that important? I dont mind running PemPro once I work the RA axis. Do I need to worry about spur gear orientation if I plan on using Pempro?

2) After cleaning , the worm/wheel surfaces still had a somewhat tacky feel to the surface though it looked quite shiny and clean throughout. Normal? Is this when you reach for mineral spirits? Why is it so important to remove mineral spirits with denatured alchohol after?

3) After re-assembly. Moving in one direction sounds realllly nice. The other direction sounds slightly more chirpy unless I put a slight load on the axis when moving it, which quiets it. Is it typical to end up with a different personality to the directions like that?

cheers
Mike in Alaska


Re: AP1200 GTO chatter

Dale Ghent
 

1. You'll need to run PEMPro for a new curve anyway, even if your spur gears stayed in the same orientation. When you do work like this, you're essentially committing to that as a step in the process; you cannot really avoid it (unless you run with PEC = off of course, and you ought to until you can generate a new curve)

2. Tacky is fine in my experience. The mineral spirits are used to dissolve grease that is caked on and hardened or just cannot be wiped out of a deep groove. The follow-up with alcohol is to remove any residue from the heavier mineral spirits so that it in turn doesn't affect the new grease you put down afterwards.

3. Not in my experience. Make sure you've tightened the worm evenly on both sides. You don't need to crank down hard on the screws either. Turn both by the same amount. This is where a sense of feel comes into play so it's kind of hard to describe how to do it over email... but whatever you do, be sure do it evenly. I'm willing to bet that this difference you notice might be because of an uneven tightening.

On May 3, 2021, at 12:25, Mike C <mike@scopenews.com> wrote:

I finally removed my DEC gearbox on my AP1200. I haven't done the RA yet. The mount has been getting a bit louder with each passing Winter and started really talking this last WInter on the first slews of the evening. I removed all the old grease and got the worm and wheel quite shiny. I applied the new grease from the AP kit.

Afterwards, inside at least, the DEC operation is quieter than I remember in a long time.

Questions -

1) I marked the spur gears with pencil but the pencil marks were lost on the plastic gear when cleaning. So.. I hope that original orientation isn't that important? I dont mind running PemPro once I work the RA axis. Do I need to worry about spur gear orientation if I plan on using Pempro?

2) After cleaning , the worm/wheel surfaces still had a somewhat tacky feel to the surface though it looked quite shiny and clean throughout. Normal? Is this when you reach for mineral spirits? Why is it so important to remove mineral spirits with denatured alchohol after?

3) After re-assembly. Moving in one direction sounds realllly nice. The other direction sounds slightly more chirpy unless I put a slight load on the axis when moving it, which quiets it. Is it typical to end up with a different personality to the directions like that?

cheers
Mike in Alaska


AP1200 GTO chatter

Mike C
 

I finally removed my DEC gearbox on my AP1200. I haven't done the RA yet. The mount has been getting a bit louder with each passing Winter and started really talking this last WInter on the first slews of the evening. I removed all the old grease and got the worm and wheel quite shiny. I applied the new grease from the AP kit.

Afterwards, inside at least, the DEC operation is quieter than I remember in a long time. 

Questions -

1) I marked the spur gears with pencil but the pencil marks were lost on the plastic gear when cleaning.  So.. I hope that original orientation isn't that important? I dont mind running PemPro once I work the RA axis. Do I need to worry about spur gear orientation if I plan on using Pempro?

2) After cleaning , the worm/wheel surfaces still had a somewhat tacky feel to the surface though it looked quite shiny and clean throughout. Normal? Is this when you reach for mineral spirits? Why is it so important to remove mineral spirits with denatured alchohol after?

3) After re-assembly. Moving in one direction sounds realllly nice. The other direction sounds slightly more chirpy unless I put a slight load on the axis when moving it, which quiets it. Is it typical to end up with a different personality to the directions like that?

cheers
Mike in Alaska


Re: Spikes in DEC #guiding #Guiding

Roland Christen
 

Hello Sebastien,

I sent you an e-mail, please check.

Roland



-----Original Message-----
From: Seb@stro <sebastiendore1@...>
To: main@ap-gto.groups.io
Sent: Sun, May 2, 2021 11:44 pm
Subject: [ap-gto] Spikes in DEC #guiding

Hello all, 

I'm having some spikes in my DEC guiding at times tonight. The worst ones seem to occur at periodic interval around 20-25 seconds but not all the time. Like about a dozen times in 400s periods. RMS values are good but DEC is about 40% bigger than RA because of these excursions. 

Conditions are fairly good now. No wind at all. Balance was quite accurate (as far as my eye can tell) in both RA and DEC. PA error reported by PHD2 is below 5 arc-min. I have a NUC on top of OTA, so no cable snag possible. Seeing is fair at 3.5-4".

My setup:
-EdgeHD 800 reduced to 1400mm FL
-Guide cam pixel scale : 1.7"/px
-Guiding through OAG at 3-4 seconds interval

Imaging M106 which is about 2hrs past meridian at the time of writing this.

That said, I'm not that familiar with guiding at such focal length... Any thoughts on what might be causing this ?

Sebastien


--
Roland Christen
Astro-Physics


Re: AP1200 regrease and maintenance

George
 

Sabino,

 

I sent you an email directly with the greasing instructions.

 

Regards,

 

George

 

George Whitney

Astro-Physics, Inc.

Phone:  815-222-6538 (direct line)

Phone:  815-282-1513 (office)

Email:  george@...

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Sabino Ramirez
Sent: Saturday, May 1, 2021 9:07 AM
To: main@ap-gto.groups.io
Subject: [ap-gto] AP1200 regrease and maintenance

 

Hi George ,

My name is Sabino Ramirez and I am from Chile, I have been looking at the group's emails and one of Linton Guise caught my attention, I have an AP1200 the same and I would like to perform a re-greasing, could you share the PDF of how to do it to my email please.

I will appreciate your help in this

 

Best regards

Sabino

My email sabino.ramirez@...

 

De: main@ap-gto.groups.io <main@ap-gto.groups.io> En nombre de George
Enviado el: viernes, 30 de abril de 2021 12:35
Para: main@ap-gto.groups.io
Asunto: [EXT] Re: [ap-gto] AP1200 regrease and maintenance

 

Linton,

 

Shoot me an email and I can send you a PDF.

 

Regards,

 

George

 

George Whitney

Astro-Physics, Inc.

Phone:  815-222-6538 (direct line)

Phone:  815-282-1513 (office)

Email:  george@...

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Linton Guise
Sent: Friday, April 30, 2021 11:26 AM
To: main@ap-gto.groups.io
Subject: [ap-gto] AP1200 regrease and maintenance

 

Hi,
My AP1200 is a few years old now but still functions perfectly. I’m sure it’s overdue for a regrease etc. Could someone direct me to any help files on how to go about this. Had a quick search but came up blank. I’m sure there must be a good guide out there.

Many thanks,

Linton Guise (Bedford U.K.)

The material contained in this email is confidential and may be subject to legal professional privilege and/or copyright. Please do not re-transmit, distribute, copy or commercialise any of the material in this message unless you are authorised to do so. If you are not the intended recipient, use, disclosure or copying of this information is prohibited. If you have received this document in error, please advise the sender and delete the document. None of Molycop, its related bodies corporate or the sender accept responsibility for any viruses contained in this email or any attachments. All and any rights as to confidentiality, legal professional privilege and copyright are expressly reserved.


Re: Spikes in DEC #guiding #Guiding

Howard Hedlund
 

Hi Sebastien,
First off, remember that the declination axis does not track unless a model is present, and then it would only be extremely slow.  Dec spikes pretty much have to come from software that is controlling the autoguiding, especially in a mount with the Absolute Encoder System like the Mach2.  I haven't had a chance to look at your PHD logs yet, but first, what software are you using along with PHD2?   APCC?  TheSkyX?  SGPro?  Something else?  If you are using APCC, please send me its zipped log files from the session above.  To use PHD2, you must have the AP V2 driver in play.  Those logs will also be valuable.
Send to:   howard at astro-physics dot com
I'm in the middle of a rush project, so please be patient with me and don't expect an analysis in the next 10 minutes!  ;^)
Also, please note that Brian V. is an excellent source of advice.  Take what he tells you seriously.
Howard Hedlund
Astro-Physics Technical Support


Re: Spikes in DEC #guiding #Guiding

Seb@stro
 

Thanks for your analysis Brian. 

What you see there is due to serious wind gusts present at the beginning of the run. I even had to remove the dew shield to help with that... But by 11:15-11:30PM, wind had entirely stopped. 

It's more with the spikes that I am concerned. By the time I saw them, conditions had greatly improved (no wind, 60% RH, -1 Celsius) compared to the beginning of the session.

At any rate, sincere thanks for chiming in. I'll see what AP thinks about that tomorrow (well, later today 🙂).

Clear skies,
Sebastien

De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Brian Valente <bvalente@...>
Envoyé : 3 mai 2021 03:03
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] Spikes in DEC #guiding #guiding
 
PS

i just found your PA run sorry i missed that

the DEC is a little bit concerning here. this is without any motor running and 3 second exposures, and yet the DEC looks remarkably uneven, especially with encoders (compare this to your RA in blue)
image.png



Re: Spikes in DEC #guiding #Guiding

 

PS

i just found your PA run sorry i missed that

the DEC is a little bit concerning here. this is without any motor running and 3 second exposures, and yet the DEC looks remarkably uneven, especially with encoders (compare this to your RA in blue)
image.png


On Sun, May 2, 2021 at 10:29 PM Seb@stro <sebastiendore1@...> wrote:
Hi Brian,

Thanks for your reply.  Logs here: https://openphdguiding.org/logs/dl/PHD2_logs_BqZp.zip

I should probably have added that my imaging scale is 1.04"/px. So it's probably impacting a bit, maybe not much... But to be honest my concern was also about the working order the mount.  

But don't get me wrong, I'm coming from a low budget asian mount and got the Mach2 about 2 months ago. It performs WAAAAAAAAYYYYYYYYYYYYYYY better, no question there. So there's the fact that I'm not very familiar with AP mounts limits regarding tracking and guiding yet. Had a handful of clear nights only. And I know my system is the challenging kind (mirrors, long FL, reducer backfocus, etc.)... So I just thought I'd ask for educated guess here.

Might also be PA as you pointed out. But I thought I did well since I polar aligned with RAPAS at the beginning of my session and refined with PHD2 polar drift align afterward. When I ran the Guiding assistant, I recall it was saying it was around 2-3 arcmin from the NCP... Do you think it's reasonable for my imaging scale (1"/px) ?

Sebastien


De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Brian Valente <bvalente@...>
Envoyé : 3 mai 2021 00:48
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] Spikes in DEC #guiding #guiding
 
Hi  Sebastien

Please upload your guidelogs for this https://openphdguiding.org/getting-help/ 


Screen caps aren't enough information, but a quick glance looks like you have pretty bad polar alignment which would dramatically impact your DEC guiding

guidelogs would tell more


I wonder how much of an issue guiding is here - your overall rms is 0.49" and your image scale is 1.7"/pix, i'm guessing even if you addressed this you may not see a difference in your images


Brian
 

On Sun, May 2, 2021 at 9:44 PM Seb@stro <sebastiendore1@...> wrote:
Hello all, 

I'm having some spikes in my DEC guiding at times tonight. The worst ones seem to occur at periodic interval around 20-25 seconds but not all the time. Like about a dozen times in 400s periods. RMS values are good but DEC is about 40% bigger than RA because of these excursions. 

Conditions are fairly good now. No wind at all. Balance was quite accurate (as far as my eye can tell) in both RA and DEC. PA error reported by PHD2 is below 5 arc-min. I have a NUC on top of OTA, so no cable snag possible. Seeing is fair at 3.5-4".

My setup:
-EdgeHD 800 reduced to 1400mm FL
-Guide cam pixel scale : 1.7"/px
-Guiding through OAG at 3-4 seconds interval

Imaging M106 which is about 2hrs past meridian at the time of writing this.

That said, I'm not that familiar with guiding at such focal length... Any thoughts on what might be causing this ?

Sebastien



--
Brian 



Brian Valente



--
Brian 



Brian Valente


Re: Spikes in DEC #guiding #Guiding

 

HI Sebastian

I suggest you take this up with AP in their forums

encoder mounts like the Mach 2 require some basic correct setup, and i'm not sure yours is there (i'm not suggesting there's anything wrong with the mount at all: you are guiding < 0.50")

 looking at a typical run, your DEC is odd for the following reasons: 
- those excursions are not the result of any PHD type of correction
- all your corrections are in one direction both RA and DEC, and corrections exhibit a clumping 

this is dec showing the large instantaneous jumps and guiding in only one direction 
image.png

image.png

I suggest you do a guiding assistant run for a few minutes to measure polar misalignment. it could be something is terribly off on polar align, but based on what you're saying i don't know. 



On Sun, May 2, 2021 at 10:29 PM Seb@stro <sebastiendore1@...> wrote:
Hi Brian,

Thanks for your reply.  Logs here: https://openphdguiding.org/logs/dl/PHD2_logs_BqZp.zip

I should probably have added that my imaging scale is 1.04"/px. So it's probably impacting a bit, maybe not much... But to be honest my concern was also about the working order the mount.  

But don't get me wrong, I'm coming from a low budget asian mount and got the Mach2 about 2 months ago. It performs WAAAAAAAAYYYYYYYYYYYYYYY better, no question there. So there's the fact that I'm not very familiar with AP mounts limits regarding tracking and guiding yet. Had a handful of clear nights only. And I know my system is the challenging kind (mirrors, long FL, reducer backfocus, etc.)... So I just thought I'd ask for educated guess here.

Might also be PA as you pointed out. But I thought I did well since I polar aligned with RAPAS at the beginning of my session and refined with PHD2 polar drift align afterward. When I ran the Guiding assistant, I recall it was saying it was around 2-3 arcmin from the NCP... Do you think it's reasonable for my imaging scale (1"/px) ?

Sebastien


De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Brian Valente <bvalente@...>
Envoyé : 3 mai 2021 00:48
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] Spikes in DEC #guiding #guiding
 
Hi  Sebastien

Please upload your guidelogs for this https://openphdguiding.org/getting-help/ 


Screen caps aren't enough information, but a quick glance looks like you have pretty bad polar alignment which would dramatically impact your DEC guiding

guidelogs would tell more


I wonder how much of an issue guiding is here - your overall rms is 0.49" and your image scale is 1.7"/pix, i'm guessing even if you addressed this you may not see a difference in your images


Brian
 

On Sun, May 2, 2021 at 9:44 PM Seb@stro <sebastiendore1@...> wrote:
Hello all, 

I'm having some spikes in my DEC guiding at times tonight. The worst ones seem to occur at periodic interval around 20-25 seconds but not all the time. Like about a dozen times in 400s periods. RMS values are good but DEC is about 40% bigger than RA because of these excursions. 

Conditions are fairly good now. No wind at all. Balance was quite accurate (as far as my eye can tell) in both RA and DEC. PA error reported by PHD2 is below 5 arc-min. I have a NUC on top of OTA, so no cable snag possible. Seeing is fair at 3.5-4".

My setup:
-EdgeHD 800 reduced to 1400mm FL
-Guide cam pixel scale : 1.7"/px
-Guiding through OAG at 3-4 seconds interval

Imaging M106 which is about 2hrs past meridian at the time of writing this.

That said, I'm not that familiar with guiding at such focal length... Any thoughts on what might be causing this ?

Sebastien



--
Brian 



Brian Valente



--
Brian 



Brian Valente


Re: Spikes in DEC #Guiding

Seb@stro
 

I seem to have some very consistant spikes (about 3" in magnitude) every 130 seconds now. I have monitored for about 20 minutes long and they are very predictable... Note that I have reduced exposure time to 2.0s, just to see if I would see more spikes when sampling faster.



Re: Spikes in DEC #guiding #Guiding

Seb@stro
 

Hi Brian,

Thanks for your reply.  Logs here: https://openphdguiding.org/logs/dl/PHD2_logs_BqZp.zip

I should probably have added that my imaging scale is 1.04"/px. So it's probably impacting a bit, maybe not much... But to be honest my concern was also about the working order the mount.  

But don't get me wrong, I'm coming from a low budget asian mount and got the Mach2 about 2 months ago. It performs WAAAAAAAAYYYYYYYYYYYYYYY better, no question there. So there's the fact that I'm not very familiar with AP mounts limits regarding tracking and guiding yet. Had a handful of clear nights only. And I know my system is the challenging kind (mirrors, long FL, reducer backfocus, etc.)... So I just thought I'd ask for educated guess here.

Might also be PA as you pointed out. But I thought I did well since I polar aligned with RAPAS at the beginning of my session and refined with PHD2 polar drift align afterward. When I ran the Guiding assistant, I recall it was saying it was around 2-3 arcmin from the NCP... Do you think it's reasonable for my imaging scale (1"/px) ?

Sebastien


De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Brian Valente <bvalente@...>
Envoyé : 3 mai 2021 00:48
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] Spikes in DEC #guiding #guiding
 
Hi  Sebastien

Please upload your guidelogs for this https://openphdguiding.org/getting-help/ 


Screen caps aren't enough information, but a quick glance looks like you have pretty bad polar alignment which would dramatically impact your DEC guiding

guidelogs would tell more


I wonder how much of an issue guiding is here - your overall rms is 0.49" and your image scale is 1.7"/pix, i'm guessing even if you addressed this you may not see a difference in your images


Brian
 

On Sun, May 2, 2021 at 9:44 PM Seb@stro <sebastiendore1@...> wrote:
Hello all, 

I'm having some spikes in my DEC guiding at times tonight. The worst ones seem to occur at periodic interval around 20-25 seconds but not all the time. Like about a dozen times in 400s periods. RMS values are good but DEC is about 40% bigger than RA because of these excursions. 

Conditions are fairly good now. No wind at all. Balance was quite accurate (as far as my eye can tell) in both RA and DEC. PA error reported by PHD2 is below 5 arc-min. I have a NUC on top of OTA, so no cable snag possible. Seeing is fair at 3.5-4".

My setup:
-EdgeHD 800 reduced to 1400mm FL
-Guide cam pixel scale : 1.7"/px
-Guiding through OAG at 3-4 seconds interval

Imaging M106 which is about 2hrs past meridian at the time of writing this.

That said, I'm not that familiar with guiding at such focal length... Any thoughts on what might be causing this ?

Sebastien



--
Brian 



Brian Valente


Re: Spikes in DEC #guiding #Guiding

 

Hi  Sebastien

Please upload your guidelogs for this https://openphdguiding.org/getting-help/ 


Screen caps aren't enough information, but a quick glance looks like you have pretty bad polar alignment which would dramatically impact your DEC guiding

guidelogs would tell more


I wonder how much of an issue guiding is here - your overall rms is 0.49" and your image scale is 1.7"/pix, i'm guessing even if you addressed this you may not see a difference in your images


Brian
 

On Sun, May 2, 2021 at 9:44 PM Seb@stro <sebastiendore1@...> wrote:
Hello all, 

I'm having some spikes in my DEC guiding at times tonight. The worst ones seem to occur at periodic interval around 20-25 seconds but not all the time. Like about a dozen times in 400s periods. RMS values are good but DEC is about 40% bigger than RA because of these excursions. 

Conditions are fairly good now. No wind at all. Balance was quite accurate (as far as my eye can tell) in both RA and DEC. PA error reported by PHD2 is below 5 arc-min. I have a NUC on top of OTA, so no cable snag possible. Seeing is fair at 3.5-4".

My setup:
-EdgeHD 800 reduced to 1400mm FL
-Guide cam pixel scale : 1.7"/px
-Guiding through OAG at 3-4 seconds interval

Imaging M106 which is about 2hrs past meridian at the time of writing this.

That said, I'm not that familiar with guiding at such focal length... Any thoughts on what might be causing this ?

Sebastien



--
Brian 



Brian Valente


Spikes in DEC #guiding #Guiding

Seb@stro
 

Hello all, 

I'm having some spikes in my DEC guiding at times tonight. The worst ones seem to occur at periodic interval around 20-25 seconds but not all the time. Like about a dozen times in 400s periods. RMS values are good but DEC is about 40% bigger than RA because of these excursions. 

Conditions are fairly good now. No wind at all. Balance was quite accurate (as far as my eye can tell) in both RA and DEC. PA error reported by PHD2 is below 5 arc-min. I have a NUC on top of OTA, so no cable snag possible. Seeing is fair at 3.5-4".

My setup:
-EdgeHD 800 reduced to 1400mm FL
-Guide cam pixel scale : 1.7"/px
-Guiding through OAG at 3-4 seconds interval

Imaging M106 which is about 2hrs past meridian at the time of writing this.

That said, I'm not that familiar with guiding at such focal length... Any thoughts on what might be causing this ?

Sebastien


Re: AP1100 loading heavy scope at 60 inch pier height

weems@...
 

Like Len, I point my 6”f9 at the floor and support it. But I take the counter weights off before I release the dovetail. The mount can hold the empty shaft in place when the scope comes off. The early AP rings are not hinged, so the scope would need to be held in place in park 2 while fumbling with a pair of cap screws for each ring.

Chip

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