Date   

Re: How Much RAPAS Misalignment is Too Much ?

Roland Christen
 

This simple polar misalignment coupled with atmospheric refraction effects. It's not field rotation, just simple drift and the amount of drift you are getting is quite normal, between 25 and 50 arc sec per hour. I get this amount also, and it will be variable depending on where the object is with respect to the zenith. The further from the zenith, the more the drift, regardless of how well polar aligned you are.

You can certainly model and compensate for it. That's what i do, but it really doesn't affect the final images in any way, except to make guiding a bit better. In fact, I have a simple model for this area of the sky which reduces the drift from 80 arc sec per hour to about 2, which lets me image 20 minutes unguided.

Rolando



-----Original Message-----
From: M Hambrick <mhambrick563@...>
To: main@ap-gto.groups.io
Sent: Fri, Sep 24, 2021 3:51 pm
Subject: Re: [ap-gto] How Much RAPAS Misalignment is Too Much ?

Hi Roland

I guess I am not sure what it is that I am seeing that I am calling field rotation. I have noticed that when I take a series of images, there is a shift in the position of the stars from the first to the last image. I decided to measure this shift using the information window in MaxIm DL to track the centroid location of the same star in successive images from first to last. The example below shows what I am seeing. I plotted the centroid coordinates over time for a series of images that I took.

In this particular example I was imaging M13. I took four 120 second subframes each of L, R, G, and B. The gaps in data are where I checked the focus whenever I switched filters, but I had the guider running continuously the whole time. You can see a relatively constant rate of change in each axis. The camera is oriented so that RA corresponds to the X-axis, and DEC corresponds to the Y-axis.

FYI I do not see any elongation in the stars in my guided images, even for 600 second subframes.

I would be grateful for any insight that you can give on this. I do not want to start messing around with the alignment screws on my RAPAS if it is not necessary. 

Mike


--
Roland Christen
Astro-Physics


Re: Rain Event Impact on Mount CP

Chris White
 

On Tue, Sep 21, 2021 at 11:00 PM, Bill Long wrote:
I have faith in the cable being the problem. I'll buy Chris a beer if it isnt. 
Bill... when are you going to buy me that beer?

Roland,

Well... the new Y cable has the same effect.  Motor stall error immediately after attempting a slew.  I've contacted george to setup a return for the CP4, however I do have a trouble shooting question just in case this could be relevant.  I noticed the other night when I was trouble shooting that I got a low power error once.  I'm using a Pyramid DC converter that delivers 5A of power.  This also got rained on and I'm wondering if it is possible that this could have been damaged and cause something like the issue I'm having.  I tested the output with a multimeter and getting 12+V of power, but that doesnt mean It's not without issue under load.  I initially ruled this out because when I switched the cable from DEC to RA, the motor stall switched from DEC to RA.  That let me to believe that it was something with the Cable or the CP4. 

Before sending the CP4 in should I buy a replacement power supply and try that first?  Could this fit?


Re: Saturn last night

thefamily90 Phillips
 

ZWO ASI290MC.
Focal Length F/14.6. No Barlow. 
A 1.6x is a bit too long. I need a 1.4x or 1.5x.

Jim


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Jeff B <mnebula946@...>
Sent: Friday, September 24, 2021 4:56:44 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Saturn last night
 
Thanks Jim.  Which ZWO camera and what was your effective focal ratio?

Jeff

On Fri, Sep 24, 2021 at 4:43 PM thefamily90 Phillips <thefamily90@...> wrote:
Hello Luca,
Thanks everyone for the kind remarks. I used a ZWO color camera. I captured about 10,000 frames at approximately 80 frames per second so about 2 minutes total capture time. I then stacked about 5,000 frames with Autostakart (?). After stacking I used wavelets in registax and then photoshop to process.

Thanks again,

Jim

From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Luca Marinelli <photo@...>
Sent: Friday, September 24, 2021 12:18:01 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Saturn last night
 
That is a really beautiful image! Crisp and clean. Obviously you have great equipment and favorable seeing but I echo the request if you wouldn’t mind sharing your acquisition and processing workflows. 

Thanks,

Luca

On Sep 24, 2021, at 11:32 AM, Jeff B via groups.io <mnebula946=gmail.com@groups.io> wrote:


Yes it is everybody's favorite, mine included!

During public events at our observatories, I always save Saturn for last, not telling anyone what they will see next.  I LOVE the reactions and exclamations of "It's not real!"  That never, ever, gets old for me.

Jeff

On Fri, Sep 24, 2021 at 11:21 AM Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:
Very nice. Pretty little planet indeed, everyone's favorite planet.

Rolando



-----Original Message-----
From: thefamily90 Phillips <thefamily90@...>
To: ap-ug@groups.io <ap-ug@groups.io>; AP-GTO Groups. io <ap-gto@groups.io>
Sent: Fri, Sep 24, 2021 9:35 am
Subject: [ap-gto] Saturn last night

AP 10” F/14.6
 
JimP
 
 
 
Sent from Mail for Windows 10
 

--
Roland Christen
Astro-Physics


Re: High Res Planetary imaging with the AP1100

Rouz
 

On exceptional nights, you can get the polar hexagon with IR filters and RGB data.

This is probably my favorite of Saturn.


Re: Saturn last night

Jeff B
 

Thanks Jim.  Which ZWO camera and what was your effective focal ratio?

Jeff

On Fri, Sep 24, 2021 at 4:43 PM thefamily90 Phillips <thefamily90@...> wrote:
Hello Luca,
Thanks everyone for the kind remarks. I used a ZWO color camera. I captured about 10,000 frames at approximately 80 frames per second so about 2 minutes total capture time. I then stacked about 5,000 frames with Autostakart (?). After stacking I used wavelets in registax and then photoshop to process.

Thanks again,

Jim

From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Luca Marinelli <photo@...>
Sent: Friday, September 24, 2021 12:18:01 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Saturn last night
 
That is a really beautiful image! Crisp and clean. Obviously you have great equipment and favorable seeing but I echo the request if you wouldn’t mind sharing your acquisition and processing workflows. 

Thanks,

Luca

On Sep 24, 2021, at 11:32 AM, Jeff B via groups.io <mnebula946=gmail.com@groups.io> wrote:


Yes it is everybody's favorite, mine included!

During public events at our observatories, I always save Saturn for last, not telling anyone what they will see next.  I LOVE the reactions and exclamations of "It's not real!"  That never, ever, gets old for me.

Jeff

On Fri, Sep 24, 2021 at 11:21 AM Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:
Very nice. Pretty little planet indeed, everyone's favorite planet.

Rolando



-----Original Message-----
From: thefamily90 Phillips <thefamily90@...>
To: ap-ug@groups.io <ap-ug@groups.io>; AP-GTO Groups. io <ap-gto@groups.io>
Sent: Fri, Sep 24, 2021 9:35 am
Subject: [ap-gto] Saturn last night

AP 10” F/14.6
 
JimP
 
 
 
Sent from Mail for Windows 10
 

--
Roland Christen
Astro-Physics


Re: High Res Planetary imaging with the AP1100

Rouz
 


Re: semi-OT: deterring critters in the obsy

Eric Baumgartner
 

For what it’s worth, Dale, my wife and I had good luck with diluted peppermint oil spray against wasps that nest behind house shingles. We used the treatment described here, and it worked famously:


We had to spray the problem wall twice over the course of a week, but after the second application, no more wasps.

Pure peppermint oil is expensive, but a little goes a long way.

Eric Baumgartner
Redding, CT USA



On Sep 24, 2021, at 4:26 PM, Dale Ghent <daleg@...> wrote:


Thanks for the feedback, everyone. I'll like a lot of these ideas. I think, for stuff under and around the mount, I'll give the pepermint extract a go first as it'll likely raise the fewest eyebrows when I tell the other users that I'll be spraying regularly for bugs around the observatory.

On Sep 17, 2021, at 16:51, Joel Short <buckeyestargazer@...> wrote:

I do two things.  
1.  Twice per year (early Spring and early Fall) I spray an insecticide called Tempo SC Ultra on the outside walls and perimeter of my roll off roof obs.  This stuff works great, for other areas of the house too.
2.  I put a little bit of peppermint extract in a small spray bottle and once a month I spray the inside of the obs, especially around any cracks.

I haven't seen a spider in years in my obs; wasps are a completely different story.  Nothing deters those buggers.

joel








Re: High Res Planetary imaging with the AP1100

Rouz
 

Thank you all, for the kind words.

Had I known you  guys enjoyed planetary images, I would have posted them sooner :)

Yes all these are with the ASI290mm. I used a PIerro Astro ADC to counter some of the effects of the low attitude.

I used the excellent AP barlow at 1.8x to 2x depending on seeing. The C14 was modified a bit with extensive insulation, internal flocking, mirror locks and an external focuser. 

There was a lot of data gathered to get one good image. Seeing isn't as good as one would think but it's more of a numbers game. Its typically some 300k to 500k frames per night but there would be many nights that result in no useable data.


Re: How Much RAPAS Misalignment is Too Much ?

M Hambrick
 

Hi Roland

I guess I am not sure what it is that I am seeing that I am calling field rotation. I have noticed that when I take a series of images, there is a shift in the position of the stars from the first to the last image. I decided to measure this shift using the information window in MaxIm DL to track the centroid location of the same star in successive images from first to last. The example below shows what I am seeing. I plotted the centroid coordinates over time for a series of images that I took.

In this particular example I was imaging M13. I took four 120 second subframes each of L, R, G, and B. The gaps in data are where I checked the focus whenever I switched filters, but I had the guider running continuously the whole time. You can see a relatively constant rate of change in each axis. The camera is oriented so that RA corresponds to the X-axis, and DEC corresponds to the Y-axis.

FYI I do not see any elongation in the stars in my guided images, even for 600 second subframes.

I would be grateful for any insight that you can give on this. I do not want to start messing around with the alignment screws on my RAPAS if it is not necessary. 

Mike


Re: High Res Planetary imaging with the AP1100

Luca Marinelli
 

Excellent detail, Rouz! Really fantastic images.

Luca 

On Sep 24, 2021, at 4:04 PM, Jeff B via groups.io <mnebula946@...> wrote:


Wicked awesome like you read about.

On Fri, Sep 24, 2021 at 3:58 PM Dale Ghent <daleg@...> wrote:
2.9um pixels so I'm thinking either a IMX290 or IMX462 chip. I'll bet it's the latter for its NIR sensitivity when used with a CH4 filter.

Amazing images for sure and at not even half-way up in the sky for him. I wish I had seeing like that.

> On Sep 24, 2021, at 15:45, Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:
>
> Those are really great. I assume you used a small Cmos color camera?
>
> Rolando
>
>
>
> -----Original Message-----
> From: Rouz <rbidshahri@...>
> To: main@ap-gto.groups.io
> Sent: Fri, Sep 24, 2021 2:40 pm
> Subject: [ap-gto] High Res Planetary imaging with the AP1100
>
> Hi everyone,
>
> Just wanted to share a few images taken with the AP1100 and C14 at about 0.1 arcseconds/pixel.
>
> The planets were tracked for several hours and lots of data was recorded with the best frames stacked and derotated.
>
> --
> Roland Christen
> Astro-Physics
>







Re: Saturn last night

thefamily90 Phillips
 

Hello Luca,
Thanks everyone for the kind remarks. I used a ZWO color camera. I captured about 10,000 frames at approximately 80 frames per second so about 2 minutes total capture time. I then stacked about 5,000 frames with Autostakart (?). After stacking I used wavelets in registax and then photoshop to process.

Thanks again,

Jim


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Luca Marinelli <photo@...>
Sent: Friday, September 24, 2021 12:18:01 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Saturn last night
 
That is a really beautiful image! Crisp and clean. Obviously you have great equipment and favorable seeing but I echo the request if you wouldn’t mind sharing your acquisition and processing workflows. 

Thanks,

Luca

On Sep 24, 2021, at 11:32 AM, Jeff B via groups.io <mnebula946@...> wrote:


Yes it is everybody's favorite, mine included!

During public events at our observatories, I always save Saturn for last, not telling anyone what they will see next.  I LOVE the reactions and exclamations of "It's not real!"  That never, ever, gets old for me.

Jeff

On Fri, Sep 24, 2021 at 11:21 AM Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:
Very nice. Pretty little planet indeed, everyone's favorite planet.

Rolando



-----Original Message-----
From: thefamily90 Phillips <thefamily90@...>
To: ap-ug@groups.io <ap-ug@groups.io>; AP-GTO Groups. io <ap-gto@groups.io>
Sent: Fri, Sep 24, 2021 9:35 am
Subject: [ap-gto] Saturn last night

AP 10” F/14.6
 
JimP
 
 
 
Sent from Mail for Windows 10
 

--
Roland Christen
Astro-Physics


Re: New Astro-Folks

Robert Berta
 

Welcome to the new team members. Eric....you dad has helped me through a few  minor issues over the years....very dedicated guy and patient.


Re: semi-OT: deterring critters in the obsy

Dale Ghent
 

Thanks for the feedback, everyone. I'll like a lot of these ideas. I think, for stuff under and around the mount, I'll give the pepermint extract a go first as it'll likely raise the fewest eyebrows when I tell the other users that I'll be spraying regularly for bugs around the observatory.

On Sep 17, 2021, at 16:51, Joel Short <buckeyestargazer@gmail.com> wrote:

I do two things.
1. Twice per year (early Spring and early Fall) I spray an insecticide called Tempo SC Ultra on the outside walls and perimeter of my roll off roof obs. This stuff works great, for other areas of the house too.
2. I put a little bit of peppermint extract in a small spray bottle and once a month I spray the inside of the obs, especially around any cracks.

I haven't seen a spider in years in my obs; wasps are a completely different story. Nothing deters those buggers.

joel


Re: semi-OT: deterring critters in the obsy

Robert Berta
 

I live in S/E MIchigan 25 miles North of Detroit and while it is a good sized housing development with thousands of people, there are coyotes near us and some times they come into the neighborhoods.  That is because of the farmland just across the street from the development. Their natural habitat is getting reduced and all those new people are providing lots of easy food...garbage and small pets. They will avoid you but not small pets and not a good idea to let a small child out by theirself.

Prior to retiring I lived and worked in Northern California in San Francisco area and when I was younger there were no problems with mountain lions....now they are everywhere. There have been a few cases of them attacking humans in California sadly and some cases of deaths. So don't tempt fate.

If you now go into San Francisco in areas like Twin Peaks and Lands End and the Presidio Park you will see signs...."Coyote Crossing". That is new also.

My astronomy buddy has a neighbor in Novato, Ca. that came home to a mountain line in their bedroom that climbed up on the lower level garage roof and patio and pulled a partially opened doorwall open and went in. Luckily when the lion saw the people it ran away. 

I manage a large observatory for Scouts here in S/E Michigan and our battle has always been with mice getting in. We tried all kinds of electronic devices from cheap to expensive. None worked...finally we completely blocked the lower part of the building with metal sheathing to cover every possible crack  and opening and prevent them from chewing the wood away to make an entrance. That MAY have worked....thus far it seems to work but give it a few more months. Those buggers are clever. 

For all the possible critter encounters....I still rate mosquitos the worst for astronomy hobby ;-) Lots itching but scarier is the disease they can spread....Lyme, West Nile, etc.  That is partially why I am now spending more time doing Solar astrophotography and less night time imaging...no mosquitos! 


Re: High Res Planetary imaging with the AP1100

Jeff B
 

Wicked awesome like you read about.


On Fri, Sep 24, 2021 at 3:58 PM Dale Ghent <daleg@...> wrote:
2.9um pixels so I'm thinking either a IMX290 or IMX462 chip. I'll bet it's the latter for its NIR sensitivity when used with a CH4 filter.

Amazing images for sure and at not even half-way up in the sky for him. I wish I had seeing like that.

> On Sep 24, 2021, at 15:45, Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:
>
> Those are really great. I assume you used a small Cmos color camera?
>
> Rolando
>
>
>
> -----Original Message-----
> From: Rouz <rbidshahri@...>
> To: main@ap-gto.groups.io
> Sent: Fri, Sep 24, 2021 2:40 pm
> Subject: [ap-gto] High Res Planetary imaging with the AP1100
>
> Hi everyone,
>
> Just wanted to share a few images taken with the AP1100 and C14 at about 0.1 arcseconds/pixel.
>
> The planets were tracked for several hours and lots of data was recorded with the best frames stacked and derotated.
>
> --
> Roland Christen
> Astro-Physics
>







Re: High Res Planetary imaging with the AP1100

Dale Ghent
 

2.9um pixels so I'm thinking either a IMX290 or IMX462 chip. I'll bet it's the latter for its NIR sensitivity when used with a CH4 filter.

Amazing images for sure and at not even half-way up in the sky for him. I wish I had seeing like that.

On Sep 24, 2021, at 15:45, Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:

Those are really great. I assume you used a small Cmos color camera?

Rolando



-----Original Message-----
From: Rouz <rbidshahri@gmail.com>
To: main@ap-gto.groups.io
Sent: Fri, Sep 24, 2021 2:40 pm
Subject: [ap-gto] High Res Planetary imaging with the AP1100

Hi everyone,

Just wanted to share a few images taken with the AP1100 and C14 at about 0.1 arcseconds/pixel.

The planets were tracked for several hours and lots of data was recorded with the best frames stacked and derotated.

--
Roland Christen
Astro-Physics


Re: High Res Planetary imaging with the AP1100

Bill Long
 

Rouz's planetary images are always wicked good. 🙂 


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Rouz <rbidshahri@...>
Sent: Friday, September 24, 2021 12:40 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] High Res Planetary imaging with the AP1100
 
Some more of Jupiter:


Re: High Res Planetary imaging with the AP1100

dvjbaja
 

These are amazing.  How different Jupiter looked one year ago.  

jg

On Fri, Sep 24, 2021 at 12:41 PM Thomas Giannaccini <tgiann3@...> wrote:
Those are amazing

On Fri, Sep 24, 2021 at 1:40 PM Rouz <rbidshahri@...> wrote:
Some more of Jupiter:


--
CN: HasAnyoneSeenMyNeblua


Re: High Res Planetary imaging with the AP1100

Karen Christen
 

Wow!  Gorgeous shots!

Karen

AP

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Rouz
Sent: Friday, September 24, 2021 2:41 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] High Res Planetary imaging with the AP1100

 

Some more of Jupiter:


--
Karen Christen
Astro-Physics


Re: High Res Planetary imaging with the AP1100

Robert Chozick <rchozick@...>
 

Wow.  Incredible. 

Roland, you need to come up with a telescope the gives views like that 😀

Robert 


On Sep 24, 2021, at 2:41 PM, Thomas Giannaccini <tgiann3@...> wrote:


Those are amazing

On Fri, Sep 24, 2021 at 1:40 PM Rouz <rbidshahri@...> wrote:
Some more of Jupiter:


--
CN: HasAnyoneSeenMyNeblua

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