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North American Nebula


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Hello all!

Last night was an absolute bliss night here for imagers and observers alike around here, not a cloud in the sky! Was excited to get my new 135mm Samyang out for a whirl, my god was I shocked! The quality of this lens is bang on!

Decided to try a widefield neb that my house isn't blocking (North west facing back garden), So I pointed it to the north american neb. Sadly not a good target for an unmodified camera, I am very reluctant to modify this as I use it for every day things also. I am not totally unhappy with the image, its clearly visible, but not what I expected, I am sure others have got 10x better in an unmodified camera. Ill upload it and the details of capturing, and hopefully someone can pass on advice :) It could be the fact its only 1 hours worth of exposure, would 3-4 hours make A LOT of difference? (Excited for longer nights). Hopefully its also in focus, I try my best, not got a batinov for this yet. It looked loads more in focus before noise reduction and such, but I kept the noise reduction in gimp as it seemed to take your eyes away from the stars and more towards the nebula with reduction.

EOS 800d

Skyguider Pro

Samyang 135mm

Lights - 38 x 90 Seconds

Darks - 30 x 90 Seconds

Bias - 23 Frames

Editted in Gimp - Stretched, Star mask, Noise reduction.

I will also upload the TIFF if anyone wants a go at editting (Would be much appreciated to see if anyone else could pull more out) :)

Thank you all!

Grant

NAsecondattempt1steditcropped.png

NAsecondattempt1stedituncropped.png

NAsecondattempt.TIF

Edited by Grant93
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Hi Grant.

Great start on a tricky target - especially recognising the lack of astro darkness.

I've had a go at your image and done the best I can - I'm sure someone with more skill at osc processing could do far better.

NA-pi-ap.thumb.jpg.d1d303a87fd4d1004f8a3a9222ec1e87.jpg

NAN and the Pelican are clearly visible.

I'm struggling to get rid of the light pollution in the bottom right without losing more of the target nebulosity; probably my inept use of PI.

I think if you could take some Flats to go with your other calibration frames that might help as well.

Adrian

 

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2 hours ago, Adreneline said:

Hi Grant.

Great start on a tricky target - especially recognising the lack of astro darkness.

I've had a go at your image and done the best I can - I'm sure someone with more skill at osc processing could do far better.

NA-pi-ap.thumb.jpg.d1d303a87fd4d1004f8a3a9222ec1e87.jpg

NAN and the Pelican are clearly visible.

I'm struggling to get rid of the light pollution in the bottom right without losing more of the target nebulosity; probably my inept use of PI.

I think if you could take some Flats to go with your other calibration frames that might help as well.

Adrian

 

Woah, I like that! A much more natural looking picture.

Shows I have a long way to go yet :D

Thanks a lot for that :)

Any tips on the editting?

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2 minutes ago, Grant93 said:

Any tips on the editting?

Hi Grant.

I'm not sure I did the best thing really.

I took the image into PixInsight and cropped off the edge effects. I then used a background extraction process to remove gradients - but not totally successfully. I then stretched the image a lttle and cloned it. With the original I removed the stars and then stretched it a lot more to reveal the nebulosity. I also used a colour saturation process to pull out the colour as best I could. The cloned image I stretched using an ArcSinh process to pull out the star colour whilst at the same time suppressing the background as much as possible. I then combined the clone with the original as a Lighten layer in PixelMath in PixInsight. Once it was combined I reset the black point a little and realigned the rgb histograms. I then ran a star reduction process in PixInsight just to tone the stars down a little. Finally I took the image out of PixInsight and did a little bit of noise reduction in an old free version of Nik Dfine2.

I am sure expert osc imagers would do far better than me but your data is good and there is plenty there to work on with nice stars. More data and darker skies and you'd be onto a winner!

HTH

Adrian

 

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1 hour ago, Adreneline said:

Hi Grant.

I'm not sure I did the best thing really.

I took the image into PixInsight and cropped off the edge effects. I then used a background extraction process to remove gradients - but not totally successfully. I then stretched the image a lttle and cloned it. With the original I removed the stars and then stretched it a lot more to reveal the nebulosity. I also used a colour saturation process to pull out the colour as best I could. The cloned image I stretched using an ArcSinh process to pull out the star colour whilst at the same time suppressing the background as much as possible. I then combined the clone with the original as a Lighten layer in PixelMath in PixInsight. Once it was combined I reset the black point a little and realigned the rgb histograms. I then ran a star reduction process in PixInsight just to tone the stars down a little. Finally I took the image out of PixInsight and did a little bit of noise reduction in an old free version of Nik Dfine2.

I am sure expert osc imagers would do far better than me but your data is good and there is plenty there to work on with nice stars. More data and darker skies and you'd be onto a winner!

HTH

Adrian

 

Thanks a lot :) Going to refer to this next time I process!

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18 hours ago, Grant93 said:

I will also upload the TIFF if anyone wants a go at editting (Would be much appreciated to see if anyone else could pull more out) :)

Hi,

I have had a very quick go at editing your image. Might be a bit over-done but I think there is a little more to get out of it. (I also do mono usually so OSC is not something I normally do).

There does seem to be some walking noise in the image, which is a bit more tricky to remove. As always more time would improve the detail. I rarely image more than on object in a night to get the most detail I can.

 

NAN quick edit.jpg

Edited by Clarkey
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11 minutes ago, Clarkey said:

Hi,

I have had a very quick go at editing your image. Might be a bit over-done but I think there is a little more to get out of it. (I also do mono usually so OSC is not something I normally do).

There does seem to be some walking noise in the image, which is a bit more tricky to remove. As always more time would improve the detail. I rarely image more than on object in a night to get the most detail I can.

 

NAN quick edit.jpg

Really nice! My image seems to look a little 'soft' (Not sure on proper terms) compared to both yours and Adrians processing. You have both pulled out a lot more.

The walking noise I assume is caused by the natural drift of my guider.. Is the only way to fix that by dithering? For which I believe I need to invest in guiding?

Thanks a lot :)

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I think I could be a bit more aggressive with the stretch because I removed the gradients before processing. I used a combination of APP, Startools and Affinity. APP to remove the gradients (even though technically ST will do this with the Wipe module, APP is better in my opinion). Startools for getting the detail and then finishing in Affinity. You could give ST a try. There is a free download with all the functionality of the paid version, but you cannot save the result. However, it is a good way to see what is possible to pull out of an image. Although ST is excellent in many ways - with really good support from Ivo, the developer - I sometimes find it is prone to over processing noise. (Probably my incompetence). However, if there is detail there it will highlight it.

To be honest given the lack of darkness at the moment and only an hour of exposure, this is a pretty good result. Longer integration really does make a difference to the Signal to noise ratio. Personally for most targets I will use all the time available in a night and often more than one session. If you look at some of the really good images on the forum they are more often than not long exposure times of 10 hrs or more. (Unless you have a RASA at F2!)

With regards to the walking noise - yes this needs guiding / dithering.

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Hi Grant - I've had a play with your image file. I've processed it in PI, theres a great deal of information in your image. There's a patch of blue in the lower right of the image I haven't tried to remove.

Can I ask if you covered the camera eyepiece during exposures as that can cause awkward patches of light on images.

My try...

 

NAsecondattempt_ABE_ABE.png

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1 hour ago, Clarkey said:

To be honest given the lack of darkness at the moment and only an hour of exposure, this is a pretty good result. Longer integration really does make a difference to the Signal to noise ratio. Personally for most targets I will use all the time available in a night and often more than one session. If you look at some of the really good images on the forum they are more often than not long exposure times of 10 hrs or more. (Unless you have a RASA at F2!)

With regards to the walking noise - yes this needs guiding / dithering.

Ill have a look at startools!

Yeah I want to start using more than one session for my images, but as I am not using a goto, its difficult to frame exactly like the last session. I've been advised a ASIair PRO will help, and can also be used to guide (with the guidescope and camera ofcourse) and dither? Obviously quite a big investment though in comparison with my current budget setup, one I do plan on making, but not in the near future. Unless there are cheaper options available :D  Thank you for your help!

2 hours ago, fwm891 said:

Hi Grant - I've had a play with your image file. I've processed it in PI, theres a great deal of information in your image. There's a patch of blue in the lower right of the image I haven't tried to remove.

Can I ask if you covered the camera eyepiece during exposures as that can cause awkward patches of light on images.

Thank you for that :) I'm not too sure where the lights come from, Derby is about 8 miles in that direction so possibly that. I am loving seeing these different edits.

That is a very good point also, I've never even thought of it, no I haven't been covering it but I definitely will from now on!

 

I've given it a go at re editting myself, trying to take into account advise given here, again only in Gimp at the moment, will download some new advised software and give it a go later! But heres the new one.

Stretched, star mask applied to protect from further stretching (did it wrong last time I think). editted the 'background' with color select on one layer, lowering the blackpoint to make it darker, then on a seperate layer increased the contrast (I think thats what its called) of the nebula seperate to the background, again with color select. Then when happy with the background and nebula, I made a 'stamp' layer (photoshop term I think?), Did a star reduction, noise reduction, and sharpened it.

NAsecondattempt3rdedit.png

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Not used Gimp but I think it's like Photoshop without ($$$$$) sign. It should have a saturation adjustment. Try small adjustments and gradually build up colour, also levels, make levels adjustment in small increments but avoid using the sliders right at the blank and white adjustment ends as that will result in clipping these areas. Adjust saturation and levels switching between them . Once you've had more practice you'll get more confidence in bigger adjustments but I still prefer keeping changes small. With a Ctrl+Z after the check on differences...

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