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My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 6:41 am
by chris_g
30 90 second subs, 10 dark, 10 flat dark, 10 flat, 10 bias using Canon T3i/600D with Optalong L-Pro Clip Filter
Telescope: Sky Watcher EvoStar ED80 on a EQ6-R Pro mount with .85 reducer/ flattener
Software used APT for image sequence and focusing, N.I.N.A. for polar alignment, mount syncing and target slewing, PHD2 Guiding
DSS used for stacking and PS for one tweak

Any suggestions for how I can improve the image are most welcome, specifically how to get more color. I am assuming longer exposure time and more subs. Framing is an obvious one, I ordered a rotator today that should show up next week. It's been an interesting journey getting to this point.

What you see is what you get,
Clear Skies!

Image

Update: 13:30 I just realized I picked the wrong plan in APT, these are 60 second subs, not 90...

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 7:51 am
by notFritzArgelander
Hi, chris_g. I'm not seeing an image?

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 7:58 am
by Butterfly Maiden
The image is showing now.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 10:23 am
by Jockinireland
Hi Chris,

Congrats of your first DSO image and its a great one at that. The stars are reasonably tight and decent colours and there is good contrast into the core.

Of course more subs (more total integration time) are always going to help but with targets like this you'd want to be careful about increasing individual subs duration too much for fear of blowing out the core. From your image above I think that you have hit the sweet spot on individual sub duration. To do better than that you'd need to be doing some longer, some shorter then combining them as HDR to get more dynamic range.

But I think there is a lot more in that data that you could pull out. If you tell us a bit more about how you processed it we can maybe help more to get you further. Specifically, did you do anything other than stack in DSS and what was your "one tweak in PS". Do you have or are you willing to get any of the astro-specific tools for PS because at this stage they can really help.

Here is a link to my M31 done with very similar kit to yours - my SW Evostar 80ED and EOS700D. Now it has a good bit more integration time - 2 hours of 120s and I think 3 hours of 240s and is combined as HDR but I really think we could get your data a good bit of the way towards this type of result.

Image

If you wanted to share your unprocessed stack straight out of DSS I'd be happy to give it a go then walk you through what I have done - that could be the best way to see what we can achieve.

Take care

David.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 11:27 am
by KathyNS
Congratulations on your first DSO image, Chris! It's a beauty!

I see plenty of colour in your image. You just have to bring it out in processing. It takes a lot more than "one tweak" to process an astro image. When DSS is finished, your work has only begun.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 12:07 pm
by Graeme1858
That's an excellent first go Chris!

For "any suggestions" definitely longer exposure. Then when you're playing in PS have a look at Levels, Curves and Saturation.

Regards

Graeme

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 12:38 pm
by notFritzArgelander
Butterfly Maiden wrote: Fri Oct 08, 2021 7:58 am The image is showing now.
For others, it seems, not for me. I can see the image in post #4 but #1 just has a box with the word image inside. I'm using an iPad with Safari if that helps.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 12:53 pm
by Butterfly Maiden
notFritzArgelander wrote: Fri Oct 08, 2021 12:38 pm
Butterfly Maiden wrote: Fri Oct 08, 2021 7:58 am The image is showing now.
For others, it seems, not for me. I can see the image in post #4 but #1 just has a box with the word image inside. I'm using an iPad with Safari if that helps.
Maybe it is a quirk with the iPad :Think:

I am using Safari on my MacBook which displays the image correctly, but I am unable to test it on an iPad. Maybe someone else can though.

Even stranger though that you can see the image in a quoted post, yet not the original.

I am in between clients at the moment nFA so I can't do much else just yet.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 1:06 pm
by notFritzArgelander
Butterfly Maiden wrote: Fri Oct 08, 2021 12:53 pm
notFritzArgelander wrote: Fri Oct 08, 2021 12:38 pm
Butterfly Maiden wrote: Fri Oct 08, 2021 7:58 am The image is showing now.
For others, it seems, not for me. I can see the image in post #4 but #1 just has a box with the word image inside. I'm using an iPad with Safari if that helps.
Maybe it is a quirk with the iPad :Think:

I am using Safari on my MacBook which displays the image correctly, but I am unable to test it on an iPad. Maybe someone else can though.

Even stranger though that you can see the image in a quoted post, yet not the original.

I am in between clients at the moment nFA so I can't do much else just yet.
It IS an iPad quirk. It’s displaying nicely on my iPhone. So now I can congratulate @chris_g on his fine first effort with sincerity.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 1:15 pm
by bobharmony
That is a nice first effort, Chris. As others have said, there is probably more available in the image you have than is showing yet. Those processing details would help give more direction on how to bring it out.

As a rule, more time on any target will help, particularly when using a filter. My personal bias is to not use filters for M31 as it is a wide spectrum object and the filter will remove some of the wavelengths that the galaxy is emitting in addition to removing background glow and LP wavelengths. This is an opinion, not an absolute direction :)

Bob

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 1:27 pm
by j.gardavsky
Hello Andro Gala!
You are well looking thanks to Chris,
JG

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 2:18 pm
by chris_g
notFritzArgelander wrote: Fri Oct 08, 2021 1:06 pm
Butterfly Maiden wrote: Fri Oct 08, 2021 12:53 pm
notFritzArgelander wrote: Fri Oct 08, 2021 12:38 pm

For others, it seems, not for me. I can see the image in post #4 but #1 just has a box with the word image inside. I'm using an iPad with Safari if that helps.
Maybe it is a quirk with the iPad :Think:

I am using Safari on my MacBook which displays the image correctly, but I am unable to test it on an iPad. Maybe someone else can though.

Even stranger though that you can see the image in a quoted post, yet not the original.

I am in between clients at the moment nFA so I can't do much else just yet.
It IS an iPad quirk. It’s displaying nicely on my iPhone. So now I can congratulate @chris_g on his fine first effort with sincerity.
@Butterfly Maiden It's probably due to how I saved the JPG, I didn't compress it at all, it's a 26MB file, I didn't want to loose any detail. I'm also hosting the image on my web site, my hosting account is on a low volume shared server. I suspect in your case it was load time. @notFritzArgelander , I have no idea why it wouldn't display on one particular device, perhaps again the size of the image???

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 2:32 pm
by Butterfly Maiden
@chris_g I think the very large image size has had a lot to do with the display issue Chris.

If you are able to store the image on another server and link to it there then you would be able to show the detail you desire.

As you say though, on a shared server you are limited, so I guess you would need to make some compromises to show your image in the best way possible.

Forums have limited file sizes that are acceptable so it is difficult to upload large files here.

Hopefully, you didn't lose much detail from your original image.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 2:47 pm
by notFritzArgelander
chris_g wrote: Fri Oct 08, 2021 2:18 pm
notFritzArgelander wrote: Fri Oct 08, 2021 1:06 pm
Butterfly Maiden wrote: Fri Oct 08, 2021 12:53 pm

Maybe it is a quirk with the iPad :Think:

I am using Safari on my MacBook which displays the image correctly, but I am unable to test it on an iPad. Maybe someone else can though.

Even stranger though that you can see the image in a quoted post, yet not the original.

I am in between clients at the moment nFA so I can't do much else just yet.
It IS an iPad quirk. It’s displaying nicely on my iPhone. So now I can congratulate @chris_g on his fine first effort with sincerity.
@Butterfly Maiden It's probably due to how I saved the JPG, I didn't compress it at all, it's a 26MB file, I didn't want to loose any detail. I'm also hosting the image on my web site, my hosting account is on a low volume shared server. I suspect in your case it was load time. @notFritzArgelander , I have no idea why it wouldn't display on one particular device, perhaps again the size of the image???
I think that is the key. I believe that the phone compressed the file but the pad struggled with it, it’s an older model. I’m looking forward to seeing it on my Mac.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 3:02 pm
by chris_g
Jockinireland wrote: Fri Oct 08, 2021 10:23 am Hi Chris,

Congrats of your first DSO image and its a great one at that. The stars are reasonably tight and decent colours and there is good contrast into the core.

Of course more subs (more total integration time) are always going to help but with targets like this you'd want to be careful about increasing individual subs duration too much for fear of blowing out the core. From your image above I think that you have hit the sweet spot on individual sub duration. To do better than that you'd need to be doing some longer, some shorter then combining them as HDR to get more dynamic range.

But I think there is a lot more in that data that you could pull out. If you tell us a bit more about how you processed it we can maybe help more to get you further. Specifically, did you do anything other than stack in DSS and what was your "one tweak in PS". Do you have or are you willing to get any of the astro-specific tools for PS because at this stage they can really help.

Here is a link to my M31 done with very similar kit to yours - my SW Evostar 80ED and EOS700D. Now it has a good bit more integration time - 2 hours of 120s and I think 3 hours of 240s and is combined as HDR but I really think we could get your data a good bit of the way towards this type of result.

Image

If you wanted to share your unprocessed stack straight out of DSS I'd be happy to give it a go then walk you through what I have done - that could be the best way to see what we can achieve.

Take care

David.
In PS, I adjusted the brightness and contrast to bring out more detail. I can get more out of it with that adjustment by itself but was concerned about noise coming out it, the background started to wash out. I am completely new to PS in this regard.

I made some adjustments in DSS based from a previous session suggested by @SkyHiker I moved the sliders until I got all three RGB channels to the left side then I adjusted the levels to get the widest base I could then adjusted the luminance to as close to an S curve as I could get that intersected as much of the three channels as I could. I was tired last night and didn't save the settings in DSS that I used, :shock: I'll get the settings I used there again when I have more time to work with it this afternoon

I'm willing to get anything needed to improve my work. If there's a cost, I will have to figure out a budget for it.

More than willing to share the data, I can make the subs available for download but it will take some time, do you want the calibration frames as well or just the lights?

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 3:07 pm
by starfield
Congratulations. First DSO is quite a milestone and your off to a great start. As Kathy said, I bet you've got more color hiding in there with some additional post processing. Also can't quite tell if you were dithering during capture or not, but if not it's definitely worth doing to help avoid "walking noise". Dithering made a big difference for me when I first got started.

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 3:19 pm
by messier 111
very beautiful first , I propose your version for photo of the day. thx .

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 3:24 pm
by chris_g
Butterfly Maiden wrote: Fri Oct 08, 2021 2:32 pm @chris_g I think the very large image size has had a lot to do with the display issue Chris.

If you are able to store the image on another server and link to it there then you would be able to show the detail you desire.

As you say though, on a shared server you are limited, so I guess you would need to make some compromises to show your image in the best way possible.

Forums have limited file sizes that are acceptable so it is difficult to upload large files here.

Hopefully, you didn't lose much detail from your original image.
Now that I have the fundamentals down on, I'll start using Astrobin since it supports complete datasets to what the technology can accomplish. Thank you...

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 3:29 pm
by chris_g
starfield wrote: Fri Oct 08, 2021 3:07 pm Congratulations. First DSO is quite a milestone and your off to a great start. As Kathy said, I bet you've got more color hiding in there with some additional post processing. Also can't quite tell if you were dithering during capture or not, but if not it's definitely worth doing to help avoid "walking noise". Dithering made a big difference for me when I first got started.
I'm not sure if it was dithering or not, N.I.N.A. new sequencer is giving me issues, so I did all set up with it then switched to APT for the actual sequence. I didn't connect anything other than the Canon in APT so I suspect no dithering was done if PHD2 doesn't do it automatically! A lot to learn!

Re: My First Successful DSO Imaging Session - Say Hello to my M 31

Posted: Fri Oct 08, 2021 5:03 pm
by Jockinireland
Hi @chris_g
I and some others prefer to work on the unadjusted tiff straight out of the stacker so if you dont have that then it may be worth putting up the raw lights as you suggest. But we will need all the calibration frames too then we can take it from first principles and really see what you got. Otherwise redo the stack but save it as a 16b tiff without any adjustment and put that up.

If it's easier for you I can make a onedrive folder available and you can upload it there. Let me know.

Take care

David