Date   

Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Chris White
 
Edited

On Tue, May 4, 2021 at 12:01 PM, sebkersten wrote:
Hi Chris
 
Thanks to share this explain.  The feedbacks are always very interesting
 
By the way, the attached picture is interesting.  Is it made in the L channel with a similar camera?
I wish I had stars like that.
 
Thanks for the feedback from Roland.  I guess with the flattener, everything is easier.
 
One more thing, could you show me a flat?
 
Sincerely
 
Sébastien
Sebastien,

That was red frame taken with the ASI 6200. 

Here is a link to a flat frame and a luminance frame so you can evaluate. 
https://www.dropbox.com/sh/sbmbxvu6nc542s0/AAD_tDVBvOiqmUNv9T5QVmE7a?dl=0


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

sebkersten
 

Hi Khushrow

I just release the mail from Chris, and I see I spelled your name wrong.  Sorry for the mistake.

Sincerely

Sébastien

Le 4 mai 2021 à 05:17, Khushrow Machhi via groups.io <kmachhi@...> a écrit :

I have the 130GTX+QTCC+ASI6200MM.  I tried very hard to get perfectly round stars at each of the four corners and after many nights of experimenting gave up after I got what I feel is close enough.  I ended up with an optimal distance in my setup at 103.1mm.  I also had 0.3mm M68 spacer rings that I used.  I believe that the small pixel size of the ASI6200 and the large image area exposes any flaws in the imaging train. I believe there is a slight tilt in my system which I tried to correct with an M68 tilt adapter but this was a futile effort.  With the current setup I get round stars in three corners but the fourth corner I do get triangles for stars at the edge and it is more noticeable if a larger star happens to be in this corner.  With the field flattener stars are round across the image with the same spacing.  I do love my 130GTX setup and the images are a joy.
Khushrow 


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

sebkersten
 

Hi Chris

Thanks to share this explain.  The feedbacks are always very interesting

By the way, the attached picture is interesting.  Is it made in the L channel with a similar camera?
I wish I had stars like that.

Thanks for the feedback from Roland.  I guess with the flattener, everything is easier.

One more thing, could you show me a flat?

Sincerely

Sébastien

Le 4 mai 2021 à 13:09, Chris White <chris.white@...> a écrit :

On Mon, May 3, 2021 at 11:17 PM, Khushrow Machhi wrote:
I have the 130GTX+QTCC+ASI6200MM.  I tried very hard to get perfectly round stars at each of the four corners and after many nights of experimenting gave up after I got what I feel is close enough.  I ended up with an optimal distance in my setup at 103.1mm.  I also had 0.3mm M68 spacer rings that I used.  I believe that the small pixel size of the ASI6200 and the large image area exposes any flaws in the imaging train. I believe there is a slight tilt in my system which I tried to correct with an M68 tilt adapter but this was a futile effort.  With the current setup I get round stars in three corners but the fourth corner I do get triangles for stars at the edge and it is more noticeable if a larger star happens to be in this corner.  With the field flattener stars are round across the image with the same spacing.  I do love my 130GTX setup and the images are a joy.
Khushrow 

My experience matches Khushrow's.  I did a lot of spacing testing with the GTX+QTCC and could not quite get perfect stars in all corners but settled in at "good enough."  Using Roland's method of finding focus and then checking corners after a few steps in and then out, revealed the sweet spot at 105.7mm.   It's odd that my spacing is quite a bit different than Khushrow's.  Spec is 102.9mm, but with a filter in the path that would be 103.9mm.  So I'm at 1.8mm over spec.  I also had a very small amount of tilt to contend with that I "mostly" corrected with a Gerd CTU. 

FWIW- Roland stated to me (through George) that you won't get perfect stars in the corners with this setup and 3.76um pixels. 

In all honesty, I do think this is good enough.  This is a MASSIVE field and with tiny pixels is still a very high resolution image.  Regardless of what camera you decide to use I'd jump on that GTX if you have the option to buy!  It's an amazing scope. 

<130GTX-QTCC-6200.jpg>


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Chris White
 

On Mon, May 3, 2021 at 11:17 PM, Khushrow Machhi wrote:
I have the 130GTX+QTCC+ASI6200MM.  I tried very hard to get perfectly round stars at each of the four corners and after many nights of experimenting gave up after I got what I feel is close enough.  I ended up with an optimal distance in my setup at 103.1mm.  I also had 0.3mm M68 spacer rings that I used.  I believe that the small pixel size of the ASI6200 and the large image area exposes any flaws in the imaging train. I believe there is a slight tilt in my system which I tried to correct with an M68 tilt adapter but this was a futile effort.  With the current setup I get round stars in three corners but the fourth corner I do get triangles for stars at the edge and it is more noticeable if a larger star happens to be in this corner.  With the field flattener stars are round across the image with the same spacing.  I do love my 130GTX setup and the images are a joy.
Khushrow 

My experience matches Khushrow's.  I did a lot of spacing testing with the GTX+QTCC and could not quite get perfect stars in all corners but settled in at "good enough."  Using Roland's method of finding focus and then checking corners after a few steps in and then out, revealed the sweet spot at 105.7mm.   It's odd that my spacing is quite a bit different than Khushrow's.  Spec is 102.9mm, but with a filter in the path that would be 103.9mm.  So I'm at 1.8mm over spec.  I also had a very small amount of tilt to contend with that I "mostly" corrected with a Gerd CTU. 

FWIW- Roland stated to me (through George) that you won't get perfect stars in the corners with this setup and 3.76um pixels. 

In all honesty, I do think this is good enough.  This is a MASSIVE field and with tiny pixels is still a very high resolution image.  Regardless of what camera you decide to use I'd jump on that GTX if you have the option to buy!  It's an amazing scope. 


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

sebkersten
 

I Khusurow

Thank you for sharing this experience.

I just saw your images on Astrobin, wow!
I understand better what you say about the corner of the image.

Perhaps you can send me 1 fit picture (unique exposure of 180 sec foe exemple, in L channel.

I could really compare the shape of the stars on the whole image, and confirm that it is this level of result that I am looking for.

Sincerely,

Sébastien

Le 4 mai 2021 à 05:17, Khushrow Machhi via groups.io <kmachhi@...> a écrit :

I have the 130GTX+QTCC+ASI6200MM.  I tried very hard to get perfectly round stars at each of the four corners and after many nights of experimenting gave up after I got what I feel is close enough.  I ended up with an optimal distance in my setup at 103.1mm.  I also had 0.3mm M68 spacer rings that I used.  I believe that the small pixel size of the ASI6200 and the large image area exposes any flaws in the imaging train. I believe there is a slight tilt in my system which I tried to correct with an M68 tilt adapter but this was a futile effort.  With the current setup I get round stars in three corners but the fourth corner I do get triangles for stars at the edge and it is more noticeable if a larger star happens to be in this corner.  With the field flattener stars are round across the image with the same spacing.  I do love my 130GTX setup and the images are a joy.
Khushrow 


Re: NGC 4565

Ross Elkins
 

Beautiful Galaxy, the classic edge on with the central bulge pretty sharp!
I can imagine floating in space seeing that thru binoculars like that🤠

Ross


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Khushrow Machhi
 

I have the 130GTX+QTCC+ASI6200MM.  I tried very hard to get perfectly round stars at each of the four corners and after many nights of experimenting gave up after I got what I feel is close enough.  I ended up with an optimal distance in my setup at 103.1mm.  I also had 0.3mm M68 spacer rings that I used.  I believe that the small pixel size of the ASI6200 and the large image area exposes any flaws in the imaging train. I believe there is a slight tilt in my system which I tried to correct with an M68 tilt adapter but this was a futile effort.  With the current setup I get round stars in three corners but the fourth corner I do get triangles for stars at the edge and it is more noticeable if a larger star happens to be in this corner.  With the field flattener stars are round across the image with the same spacing.  I do love my 130GTX setup and the images are a joy.
Khushrow 


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Malik AMZIANE
 

         ---  Yes, 100.6mm is correct for the GT lens. If you focus for best focus in the corners, the stars overall should be sharp and round.-----

I thought the GT and GTX lenses were identical apart from the oil bath, interesting to learn!
 
Does this imply that with a GTX the result in the corners will be better? Or easier to obtain?
 
In this image, I just manually adjusted the focus and this is the best result I got, as you can see on the astap analysis, the center is higher than the corners. When I do autofocus, it's the opposite (2.60 in the center and more than 3.00 in the corners) but in this case the corners are even worse.

        ------  
I have also tested this combination with movements of 0.2mm. -------

Fred I would be curious to see your result, it will be interesting to compare.
 
I enclose a wetransfer link with the complete image.
And here is a close-up on the 4 corners,

https://we.tl/t-VN3f0viM55



Malik


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Roland Christen
 


triangle shape seems odd.
It will be triangle if it is slightly out of focus in the corners.

Rolando


-----Original Message-----
From: Fredd Drevon <frdrevon@...>
To: main@ap-ug.groups.io
Sent: Mon, May 3, 2021 6:28 pm
Subject: Re: [ap-ug] Info about 130GTX + 0.72x QuadTCC + ASI6200

Can you share a link to your frame. It is quite difficult to see the shape of stars. I have also tested this combination with movements of 0.2mm. I don't think you can get round stars in the corner but triangle shape seems odd.


On 3 May 2021, at 21:48, Malik AMZIANE <malik.amziane@...> wrote:


Hello all,
 
I was just going to open a discussion on this subject to seek the advice of Master Roland.
I received this week the focuser 3.5 to upgrade my AP130GT, in order to mount the QuadTCC on it.
I did 2 nights of testing with an ASI6200 and I can't manage to get perfectly picky stars in the corners.
 
I did about ten assemblies with different distances to 0.3mm and here is the best result I get.
 
I don't know if this is normal, if I have reached the maximum of what the Ap130/Quad combo can give. Or if I can still improve?
I had to adjust a slight tilt, and when I add or remove 0.5mm the field curvature increases.
For the settings I use CCDInspectore and ASTAP.
 
Maybe I am too demanding? The stars in the corners are not perfectly round but rather triangular.
 
I specify that before that I had mounted the QuadTCC on an LZOS 152F8, I managed to set the backfocus perfectly and I get perfect and round stars in the corners.
 
Also I find it strange that the ideal distance I found is 100.6mm when it is supposed to be 103.8 + 1mm for the spacer of my filters.
 
Am I missing something?
 
Sorry to ask questions more than I answer Sebastien
 
To the pleasure,
Malik

<3- BEST FOCUS CURV 17.4.jpg>
<ccdi.png>
<ASTAP.png>


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Roland Christen
 


Also I find it strange that the ideal distance I found is 100.6mm
Yes, 100.6mm is correct for the GT lens. If you focus for best focus in the corners, the stars overall should be sharp and round.

Rolando


-----Original Message-----
From: Malik AMZIANE <malik.amziane@...>
To: main@ap-ug.groups.io
Sent: Mon, May 3, 2021 3:48 pm
Subject: Re: [ap-ug] Info about 130GTX + 0.72x QuadTCC + ASI6200

Hello all,
 
I was just going to open a discussion on this subject to seek the advice of Master Roland.
I received this week the focuser 3.5 to upgrade my AP130GT, in order to mount the QuadTCC on it.
I did 2 nights of testing with an ASI6200 and I can't manage to get perfectly picky stars in the corners.
 
I did about ten assemblies with different distances to 0.3mm and here is the best result I get.
 
I don't know if this is normal, if I have reached the maximum of what the Ap130/Quad combo can give. Or if I can still improve?
I had to adjust a slight tilt, and when I add or remove 0.5mm the field curvature increases.
For the settings I use CCDInspectore and ASTAP.
 
Maybe I am too demanding? The stars in the corners are not perfectly round but rather triangular.
 
I specify that before that I had mounted the QuadTCC on an LZOS 152F8, I managed to set the backfocus perfectly and I get perfect and round stars in the corners.
 
Also I find it strange that the ideal distance I found is 100.6mm when it is supposed to be 103.8 + 1mm for the spacer of my filters.
 
Am I missing something?
 
Sorry to ask questions more than I answer Sebastien
 
To the pleasure,
Malik


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Roland Christen
 

Do you have a closeup picture of your corner stars?

Rolando

-----Original Message-----
From: Malik AMZIANE <malik.amziane@...>
To: main@ap-ug.groups.io
Sent: Mon, May 3, 2021 3:48 pm
Subject: Re: [ap-ug] Info about 130GTX + 0.72x QuadTCC + ASI6200

Hello all,
 
I was just going to open a discussion on this subject to seek the advice of Master Roland.
I received this week the focuser 3.5 to upgrade my AP130GT, in order to mount the QuadTCC on it.
I did 2 nights of testing with an ASI6200 and I can't manage to get perfectly picky stars in the corners.
 
I did about ten assemblies with different distances to 0.3mm and here is the best result I get.
 
I don't know if this is normal, if I have reached the maximum of what the Ap130/Quad combo can give. Or if I can still improve?
I had to adjust a slight tilt, and when I add or remove 0.5mm the field curvature increases.
For the settings I use CCDInspectore and ASTAP.
 
Maybe I am too demanding? The stars in the corners are not perfectly round but rather triangular.
 
I specify that before that I had mounted the QuadTCC on an LZOS 152F8, I managed to set the backfocus perfectly and I get perfect and round stars in the corners.
 
Also I find it strange that the ideal distance I found is 100.6mm when it is supposed to be 103.8 + 1mm for the spacer of my filters.
 
Am I missing something?
 
Sorry to ask questions more than I answer Sebastien
 
To the pleasure,
Malik


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Fredd Drevon
 

Can you share a link to your frame. It is quite difficult to see the shape of stars. I have also tested this combination with movements of 0.2mm. I don't think you can get round stars in the corner but triangle shape seems odd.


On 3 May 2021, at 21:48, Malik AMZIANE <malik.amziane@...> wrote:


Hello all,
 
I was just going to open a discussion on this subject to seek the advice of Master Roland.
I received this week the focuser 3.5 to upgrade my AP130GT, in order to mount the QuadTCC on it.
I did 2 nights of testing with an ASI6200 and I can't manage to get perfectly picky stars in the corners.
 
I did about ten assemblies with different distances to 0.3mm and here is the best result I get.
 
I don't know if this is normal, if I have reached the maximum of what the Ap130/Quad combo can give. Or if I can still improve?
I had to adjust a slight tilt, and when I add or remove 0.5mm the field curvature increases.
For the settings I use CCDInspectore and ASTAP.
 
Maybe I am too demanding? The stars in the corners are not perfectly round but rather triangular.
 
I specify that before that I had mounted the QuadTCC on an LZOS 152F8, I managed to set the backfocus perfectly and I get perfect and round stars in the corners.
 
Also I find it strange that the ideal distance I found is 100.6mm when it is supposed to be 103.8 + 1mm for the spacer of my filters.
 
Am I missing something?
 
Sorry to ask questions more than I answer Sebastien
 
To the pleasure,
Malik

<3- BEST FOCUS CURV 17.4.jpg>
<ccdi.png>
<ASTAP.png>


Re: [ap-gto] [ap-ug] A colorful Southern Sky Beauty

ROBERT WYNNE
 

Did a little more research on the quality of pre-1990 lens fabrication. The running theme is that almost all camera lenses were figured with particular attention paid only the about the center third of the lens. Everything beyond that is poorly figured. Today's lenses are figured to a much higher standard to conform (as you stated) to CCD pixel geometries. Here I have to wonder if each camera's CCD even though sold as an equal to its market is precisely as equal as we may demand. -Best, Robert  

On 05/01/2021 11:53 AM Roland Christen via groups.io <chris1011@...> wrote:
 
 
Ne ver seen one but probably a very good lens.
 
Rolando
 
 
 
-----Original Message-----
From: ROBERT WYNNE <robert-wynne@...>
To: main@ap-ug.groups.io; Roland Christen via groups.io <chris1011@...>
Sent: Sat, May 1, 2021 1:13 pm
Subject: Re: [ap-gto] [ap-ug] A colorful Southern Sky Beauty

Any opines on fluorite lenses from 40 years ago. I have what at the time was a fairly expensive Canon fluorite telephoto lens that was specifically designed to "eliminate" chromatic aberration. -Best, Robert
On 05/01/2021 10:00 AM Roland Christen via groups.io <chris1011@...> wrote:
 
 
I have studied lenses and lens design for a generation. What is possible today versus 40 years ago is an order of magnitude improvement. The reason is that back then we did not have fluorite based low dispersion glass (ED and SD glass) available. Development of real glass with fluorite as the main ingredient was the breakthrough that was needed to make high resolution possible. It was not lanthanum because that was always around since day1. It was not fluorite crystal either since that was always available but had many drawbacks for mass production (high cost, fragile during processing).
 
The main driving force for ED lenses was sports photography and digital color television along with the flat screens that replaced the old cathode ray tubes. All of a sudden flat screen TV images were of high enough resolution that you could see the effects of chromatic aberration when the cameras zoomed in on the players down on the field. Camera manufacturers scrambled to produce higher performance lenses to meet the new resolution requirements. If you look at any old TV shows from the '60s you will see the green and purple fringing when the camera zoomed in on a subject.
 
Rolando
 
-----Original Message-----
From: Alan Friedman <alan@...>
To: main@ap-ug.groups.io
Sent: Sat, May 1, 2021 11:20 am
Subject: Re: [ap-gto] [ap-ug] A colorful Southern Sky Beauty

One of the old film lenses that was designed for sharpness over a wide field at maximum aperture was the Noct-Nikkor 58 f1.2. It was made in relatively small numbers with a hand-aspherized front surface element. The goal of the design as I understand it was to minimize coma in point sources of light to the corners of the frame. I used it a little last summer to photograph the comet… never got a good sense of its potential from the city location I was shooting from. 
 
I don’t have experience with medium format systems but in 35mm format lens designs for digital are all over the place. Leica is reissuing historic designs that bring intentional softness wide open. They are also introducing f2 lenses with apo-asph designations that are said to deliver remarkable correction across the full frame. These small manual focus lenses are $8000+ - I haven’t tried one. Cosina in Japan is producing several lenses with a similar goal under the Voigtlander name. I have used these Apo-Lanthar lenses and at f2 they are incredibly sharp. Chromatic aberration is very well controlled into the corners of the frame. There is vignetting wide open which improves at f2.8. About 1/8 the cost of Leica - an interesting option to pair with a 61mp 24x36mm sensor. 
 
 
Alan Friedman

On May 1, 2021, at 11:08 AM, Roland Christen via groups.io < chris1011@...> wrote:

 
I have seen MANY stunning results taken with very humble equipment (ex Canon EOS 70-200/f4L)
Sure, I agree, but that is not one of the old lenses made for film cameras. The original question was how good those old film camera lenses were. The answer that I got from my Pentax lens was - basically horrible at full aperture. Stopped down to near pinhole size - ok but very little light gathering power. Compared to a cheap and cheerful Rokinon that i bought for Milky way imaging, the old lens doesn't come close. The Rokinon is sharp even wide open. Take a look at my recent image that i posted of the Zodiacal Light. That was taken with the Rokinon at F2.
 
I have old Nikon lenses, including the original all-around 50mm F1.4 lens that most people used with their 35mm Nikon film cameras. Wide open it gathers a lot of light. Unfortunately that light is spread out over a huge blur circle, especially in the blue and red end, so that bright stars all have huge halos. These lenses were basically achromats, and fast achromats have horrible chromatic aberrations.
 
Rolando
 
 
 


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

Malik AMZIANE
 

Hello all,
 
I was just going to open a discussion on this subject to seek the advice of Master Roland.
I received this week the focuser 3.5 to upgrade my AP130GT, in order to mount the QuadTCC on it.
I did 2 nights of testing with an ASI6200 and I can't manage to get perfectly picky stars in the corners.
 
I did about ten assemblies with different distances to 0.3mm and here is the best result I get.
 
I don't know if this is normal, if I have reached the maximum of what the Ap130/Quad combo can give. Or if I can still improve?
I had to adjust a slight tilt, and when I add or remove 0.5mm the field curvature increases.
For the settings I use CCDInspectore and ASTAP.
 
Maybe I am too demanding? The stars in the corners are not perfectly round but rather triangular.
 
I specify that before that I had mounted the QuadTCC on an LZOS 152F8, I managed to set the backfocus perfectly and I get perfect and round stars in the corners.
 
Also I find it strange that the ideal distance I found is 100.6mm when it is supposed to be 103.8 + 1mm for the spacer of my filters.
 
Am I missing something?
 
Sorry to ask questions more than I answer Sebastien
 
To the pleasure,
Malik


Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

sebkersten
 

Hi David

Thanks for your advise.

Would you have some pictures to show me? This would be great.
Of, maybe, you could send me a single image (fit), via a Wtransfert or dropbox.

Thank you for your help

Sincincerely,

Sébastien

Le 3 mai 2021 à 21:36, David via groups.io <phrosty5=yahoo.com@groups.io> a écrit :

They’ll be fine. I have the same setup except it’s a 130GT. Corners are good with my QHY600.

David


On May 3, 2021, at 1:23 PM, sebkersten <sebastien.kersten@gmail.com> wrote:

Hi,

I use an ASI6200 camera for my deep sky photography. I have the opportunity to buy a 130GTX with the QuadTCC reducer.

I am looking for information and examples of images made with this material. I would like to see how the stars are in the corners of the image. Indeed, with the ASI6200, there is no tolerance.

For info, actually I us use a TOA130NFB and the TOA-35 reducer. The image circle is 44mm.
If in h-alpha, the elongation of the stars in the corners is acceptable, in luminance the deformation is too important.

That's why I'm looking to the 130GTX.

Thanks in advance for your help.

Sincerely

Sébastien












Re: Info about 130GTX + 0.72x QuadTCC + ASI6200

David
 

They’ll be fine. I have the same setup except it’s a 130GT. Corners are good with my QHY600.

David

On May 3, 2021, at 1:23 PM, sebkersten <sebastien.kersten@gmail.com> wrote:

Hi,

I use an ASI6200 camera for my deep sky photography. I have the opportunity to buy a 130GTX with the QuadTCC reducer.

I am looking for information and examples of images made with this material. I would like to see how the stars are in the corners of the image. Indeed, with the ASI6200, there is no tolerance.

For info, actually I us use a TOA130NFB and the TOA-35 reducer. The image circle is 44mm.
If in h-alpha, the elongation of the stars in the corners is acceptable, in luminance the deformation is too important.

That's why I'm looking to the 130GTX.

Thanks in advance for your help.

Sincerely

Sébastien








Info about 130GTX + 0.72x QuadTCC + ASI6200

sebkersten
 

Hi,

I use an ASI6200 camera for my deep sky photography. I have the opportunity to buy a 130GTX with the QuadTCC reducer.

I am looking for information and examples of images made with this material. I would like to see how the stars are in the corners of the image. Indeed, with the ASI6200, there is no tolerance.

For info, actually I us use a TOA130NFB and the TOA-35 reducer. The image circle is 44mm.
If in h-alpha, the elongation of the stars in the corners is acceptable, in luminance the deformation is too important.

That's why I'm looking to the 130GTX.

Thanks in advance for your help.

Sincerely

Sébastien


Re: NGC 4565

Stuart
 

Nice 1st light!!! Classic treatment!


On Mon, 3 May 2021 at 10:59, <skester@...> wrote:
I purchased my new 1100GTO to allow me to run a larger, faster scope and still have the weight of the mount be manageable since I travel to image.  I have since acquired a 12" F4 newtonian and shot NGC 4565 as the first light last night.  20 minutes each RGB and 1 hour of luminance with a ASI1600MM-Pro.


NGC 4565

skester@...
 

I purchased my new 1100GTO to allow me to run a larger, faster scope and still have the weight of the mount be manageable since I travel to image.  I have since acquired a 12" F4 newtonian and shot NGC 4565 as the first light last night.  20 minutes each RGB and 1 hour of luminance with a ASI1600MM-Pro.


Re: NGC 6888 Crescent Nebula

Stuart
 

Nicely done Peter!


On Sun, 2 May 2021 at 10:57, Peter Bresler via groups.io <PABresler=aol.com@groups.io> wrote:
This is 14 hours integration time with my 1200 using 15 and 20 minute guided exposures with an OAG of the Planewave CDK12.5, Apogee U16M camera.

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