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Skywatcher AZ GTI mount owners thread


AstroNebulee

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11 hours ago, herne said:

I had a quick play.  There's some decent data in there, not only of the Crescent Nebula but also of other surrounding nebulosity 👍.

Below are two pictures.  The first is a simple process of your raw tiff file using Siril only.  The second is taking that file processed in Siril and running it through Photoshop with some basic curves and a little gausian blur to help with some of the aberration.  It's still a bit noisy which with some extra time I could reduce and perhaps make some other improvements too, but hopefully you get the idea.

Some stars do still seem to be a little misshapen, although only really noticeable if you zoom right in.  But overall you've got some good data in there, perhaps more than you may realise 🙂.

 

 

I have heard nothing but good things about SIRIL.

And I do have Siril, I also have the webpage which walks you through it's use.

So I think given what you have shown me with it's use it's about time I learned how to use it 😅.

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32 minutes ago, bomberbaz said:

I have heard nothing but good things about SIRIL.

And I do have Siril, I also have the webpage which walks you through it's use.

So I think given what you have shown me with it's use it's about time I learned how to use it 😅.

You can use it for stacking and/or some basic processing.

I tend to experiment with stacking between DSS and Siril and use the stacked version I like the best.  For my Sadr pic on the previous page I used DSS then Photoshop, didn't touch Siril.  But for my recent Whirlpool galaxy pic I preferred the stack which Siril produced, then did some light processing in Siril before switching to PS.  It's just trial and error.

With your Crescent nebula data it looked like there was some gradient in it which can be dealt with in PS but I find it easier to deal with using Siril.  So with your tif file I used Siril for a quick auto stretch followed by a colour calibration, then a background extraction to help with gradient and finished with the green noise removal tool (you'll see what I mean when you start using it).  It took me 5 mins.

Siril can be more complex but I find that quick & simple workflow suits me just fine.  I've only been using the program for a few months - I watched some YT videos and just practised with some data 👍.

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@bomberbaz  Actually I should list the exact Siril workflow I used for your data:

Open the tif file in Siril.

At the bottom middle, change "Linear" to "Autostretch".

If you flick through the Red/Green/Blue/RGB channel tabs at the top, they'll all be shades of grey except the RGB channel which will be bright green.

From the top, select Image Processing > Color Calibration > Photometric Color Calibration.

In the window which appears, select the "Image Parameters" box, type in NGC6888 and click Find.

Some options should appear underneath after clicking Find.  Select Simbad Crescent Nebula (or NED NGC6888 if you don't get that option).  Then click OK.

Wait for it to complete and click close.  The bright green RGB picture should disappear and be replaced with something looking better but suffering from gradient.  The Crescent will be in the centre against a greenish/black night sky and framed by reddish clouds.

Select the Blue Red or Green channel but not the RGB channel.

Select Image Processing > Background Extraction.

Use these settings in the window which appears:  Degree order 4; Samples per line 20; Tolerance 1.00; leave Add Dither unchecked.  Click Generate.

A load of small green boxes will appear.  Right click on whichever green boxes touch or are very near to the Crescent nebula to make them disappear.  (You can't get rid of boxes if in the RGB channel, hence changing to one of the others).  I got rid of 4 boxes.  You don't want them touching your target as that'll make the program think it's part of the gradient.  Click Apply then Close when it's finished.

Click on the RGB channel and your picture should now be looking pretty nice.

Select Image Processing > Remove Green Noise.  Make sure the Protection Method is set to Average Neutral, tick Preserve Lightness and click Apply.  Close the window when done.

At the middle bottom, change Autostretch to Linear.  The screen will go all black again.

Select Image Processing > Histogram Transformation.  A window will appear with a line graph in it.

Just below the line graph there are 6 icons.  Click the one on the right which looks like a cog wheel with an S curve running through it.

Your picture will reappear.  Click Apply then Close.

The night sky will have a blueish tinge which I sorted out in Photoshop with a basic "S" curve.  I guess GIMP could do the same.

Now save it as a 16 bit tif file for use in Photoshop or GIMP.  (Right click on the image > Save RGB image to TIFF > give it a filename > select 16 bit unsigned integer).

That's it 👍.

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1 hour ago, herne said:

@bomberbaz  Actually I should list the exact Siril workflow I used for your data:

Open the tif file in Siril.

At the bottom middle, change "Linear" to "Autostretch".

If you flick through the Red/Green/Blue/RGB channel tabs at the top, they'll all be shades of grey except the RGB channel which will be bright green.

From the top, select Image Processing > Color Calibration > Photometric Color Calibration.

In the window which appears, select the "Image Parameters" box, type in NGC6888 and click Find.

Some options should appear underneath after clicking Find.  Select Simbad Crescent Nebula (or NED NGC6888 if you don't get that option).  Then click OK.

Wait for it to complete and click close.  The bright green RGB picture should disappear and be replaced with something looking better but suffering from gradient.  The Crescent will be in the centre against a greenish/black night sky and framed by reddish clouds.

Select the Blue Red or Green channel but not the RGB channel.

Select Image Processing > Background Extraction.

Use these settings in the window which appears:  Degree order 4; Samples per line 20; Tolerance 1.00; leave Add Dither unchecked.  Click Generate.

A load of small green boxes will appear.  Right click on whichever green boxes touch or are very near to the Crescent nebula to make them disappear.  (You can't get rid of boxes if in the RGB channel, hence changing to one of the others).  I got rid of 4 boxes.  You don't want them touching your target as that'll make the program think it's part of the gradient.  Click Apply then Close when it's finished.

Click on the RGB channel and your picture should now be looking pretty nice.

Select Image Processing > Remove Green Noise.  Make sure the Protection Method is set to Average Neutral, tick Preserve Lightness and click Apply.  Close the window when done.

At the middle bottom, change Autostretch to Linear.  The screen will go all black again.

Select Image Processing > Histogram Transformation.  A window will appear with a line graph in it.

Just below the line graph there are 6 icons.  Click the one on the right which looks like a cog wheel with an S curve running through it.

Your picture will reappear.  Click Apply then Close.

The night sky will have a blueish tinge which I sorted out in Photoshop with a basic "S" curve.  I guess GIMP could do the same.

Now save it as a 16 bit tif file for use in Photoshop or GIMP.  (Right click on the image > Save RGB image to TIFF > give it a filename > select 16 bit unsigned integer).

That's it 👍.

+1 for Siril, definitely worth persevering 👍🏻

Processed my Monkey head with it (it's on this thread somewhere)

Edited by knobby
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2 hours ago, bomberbaz said:

Thanks @herne for that, I shall give that a go later on to see how I get on. 

I still intend reading this too as it should hopefully give me a better understanding of what is actually happening Siril - Manual pre-processing

However in the interim your walkthrough will come in very handy. 👌

Yeh definitely have read of the manual 👍. I didn’t want to go into detail above about what it all means, just a quick overview to get started 👍

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Hoping to get a half hours worth of imaging tonight after tinkering and tightening everything up on the rig. 

Hopefully it has improved but just going to try adding another 30 minutes to my crescent data. 

Sky looking reasonable and cloud clearing nicely.

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1 hour ago, bomberbaz said:

another 30 minutes to my crescent data

That's dedication, I won't move unless it's 3-4 hours clear. No wonder I have so many projects on the go...

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8 hours ago, Priesters said:

At the caravan in the Lake District at the mo.  Having another go at the veil and going ok so far by my standards 🤞

image.thumb.png.8b3b4d263700931b67e3aa4773ec1fed.pngimage.thumb.png.186ce8a7f287c52bd5c704cdb019b6bd.png

Are you using a reducer, I can only just fit the veil into my view field, just. 

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Hello all. Well managed to grab another 30 minutes data last night and the difference was very noticeable in both terms of star shape and more over, the end result.

The tracking seemed to be behaving itself much better last night but I just wish i would learn to leave well alone, haha.

Anyway, I did push the data through SiriL first and then had a tinker in Gimp after that and end result is below.

I am still learning a lot and when I have the patience to sit down and learn it some more no doubt results will get a little better.

400867623_crescentsirilgimp.thumb.jpg.3c9cdb662eb593540cfbd3a145d10f8d.jpg

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1 hour ago, bomberbaz said:

Are you using a reducer, I can only just fit the veil into my view field, just. 

It’s actually the Starizona Evo FF2 which is meant to be just a field flattener but as you’ve noticed there is definitely a reduction factor involved.  I measured it a while back at approx 0.9.  It has 55mm back focus too which has meant I can add a filter drawer and rotator in the train.  Your Crescent is very nice btw - you may still be learning but your processing is still several steps ahead of mine 😀

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21 minutes ago, Priesters said:

It’s actually the Starizona Evo FF2 which is meant to be just a field flattener but as you’ve noticed there is definitely a reduction factor involved.  I measured it a while back at approx 0.9.  It has 55mm back focus too which has meant I can add a filter drawer and rotator in the train.  Your Crescent is very nice btw - you may still be learning but your processing is still several steps ahead of mine 😀

I think I may lay out for one of those, the addition of the filter drawer and reduction factor are both attractive options. Can you send me a pic of the focal train please

cheers

steve

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1 hour ago, bomberbaz said:

Hello all. Well managed to grab another 30 minutes data last night and the difference was very noticeable in both terms of star shape and more over, the end result.

The tracking seemed to be behaving itself much better last night but I just wish i would learn to leave well alone, haha.

Anyway, I did push the data through SiriL first and then had a tinker in Gimp after that and end result is below.

I am still learning a lot and when I have the patience to sit down and learn it some more no doubt results will get a little better.

400867623_crescentsirilgimp.thumb.jpg.3c9cdb662eb593540cfbd3a145d10f8d.jpg

I’d say that’s definitely better than your previous picture - you’ve brought out more of the surrounding nebulosity and there is a better overall colour calibration 👍.

Additional integration time will of course be useful but there’s a marked difference already between your two pictures and you’re on the right track 😀.

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13 minutes ago, herne said:

I’d say that’s definitely better than your previous picture - you’ve brought out more of the surrounding nebulosity and there is a better overall colour calibration 👍.

Additional integration time will of course be useful but there’s a marked difference already between your two pictures and you’re on the right track 😀.

Thanks, thinking back I overused background equalisation tools using py-astro, this clears gradiant but if over done kills nebulosity too. 

Less is more is certainly the key on nebula. 

That said, I think I really like SiriL, just started going through user guide but I think I pretty much get what the automated process was doing that you put up, cheers

steve

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I'm sure this has been covered here already but I can't find it so here goes.

I'm still keen to use Skysafari for observing with this mount, last night I fired up the app and it connected fine to my  Az GTi in AZ mode (still with the pre EQ/AZ firmware). All I then did was to select Arcturus in Skysafari, the mount slewed and it tracked OK. So, knowing that new firmware has been released I updated the Az GTi firmware from the original AZ only mode to the dual mode. I reset everything, opened up Skysafari, connected the scope which took me to the choice between EQ and AZ mode and selected AZ. Skysafari then re=opened and I once again selected Arcturus whereupon the mount slewed to a point below the horizon.

Now I'm pretty sure this is something to do with left side/right side scope connection to the mount, but it was late and I was tired so I called it a night. I've spent a part of today looking for other peoples observations but everything seems to be about using the mount in EQ mode for astrophotography and not observing in AZ mode with the new dual mode firmware, I'd be grateful for any views on this.

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Thought I'd share this - I had my first attempt at M16 last night (2 min subs).  Not an easy target for me as neighbouring rooflines obscure all vision until around 2330 plus it's comparatively low in the sky and south for me is towards Canterbury, so a fair amount of light coming up.  I also noticed I'd need to do a meridian flip at about 1am, something I don't usually get too involved with.

But I thought lets give it a crack.  And I have to say the AZ GTi + AAP performed flawlessly for the meridian flip.  I stayed up to make sure it all went smoothly and to be honest I didn't need to bother.  A few tentative minutes waiting after the flip for everything to settle, restart guiding and imaging but it all worked just fine and didn't need any interference from me.  It really is a cracking little mount, continues to impress and I think is just an ideal partner for the AAP.

Anyway, images below (wide field and crop) - just under 3 hours integration (I could use more and am keeping an eye on the sky to add more soon I hope) along with some Dark frames.  I may see if I can split out the RGB and make a pseudo-Hubble palette image.

PS processed wide.jpg

PS processed detail.jpg

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On 26/06/2022 at 16:33, LaurenceT said:

I'm sure this has been covered here already but I can't find it so here goes.

I'm still keen to use Skysafari for observing with this mount, last night I fired up the app and it connected fine to my  Az GTi in AZ mode (still with the pre EQ/AZ firmware). All I then did was to select Arcturus in Skysafari, the mount slewed and it tracked OK. So, knowing that new firmware has been released I updated the Az GTi firmware from the original AZ only mode to the dual mode. I reset everything, opened up Skysafari, connected the scope which took me to the choice between EQ and AZ mode and selected AZ. Skysafari then re=opened and I once again selected Arcturus whereupon the mount slewed to a point below the horizon.

Now I'm pretty sure this is something to do with left side/right side scope connection to the mount, but it was late and I was tired so I called it a night. I've spent a part of today looking for other peoples observations but everything seems to be about using the mount in EQ mode for astrophotography and not observing in AZ mode with the new dual mode firmware, I'd be grateful for any views on this.

Hi Laurence, I don't use mine in AZ mode but in the absence of any answers I'd suggest trying the scope on the other side maybe ... don't need to wait till dark, just use the moon or something easy as a traget.

Best of luck 🙂

 

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22 minutes ago, knobby said:

Hi Laurence, I don't use mine in AZ mode but in the absence of any answers I'd suggest trying the scope on the other side maybe ... don't need to wait till dark, just use the moon or something easy as a traget.

Best of luck 🙂

 

Thanks for that. I realised yesterday that Skywatcher had released a version that was for AZ only so I flashed that firmware instead. The original reason for me doing this was that Skywatcher said this new firmware would improve compatibility with third party apps so hopefully this will be the case with Skysafari which has been a bit temperamental recently.

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