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Bode's Nebula - Messier 81


PhotoGav

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Bode's Nebula - Messier 81

On December 31st 1774, Johann Bode shunned the New Year's Eve celebrations in favour of slewing his telescope to a patch of sky just above the head of the Great Bear. He found two nebulous patches 'very pale and of elongated shape'. His kit was unable to resolve much detail in these areas and they were thought to be nebulae within our own galaxy. A few years later the patches were rediscovered by Pierre Mechain and Charles Messier. They didn't move, much to the frustration of Messier, annoyed to have found another comet candidate that turned out not to be a comet. So, the coordinates were added to his list of areas of sky to avoid in future comet hunts and catalogued as Messier 81 and Messier 82.

Here we have my image of Messier 81, also known as Bode's Nebula or Bode's Galaxy in homage to its original discoverer; it is a tight SA spiral galaxy some 12 million light years from Earth in the constellation of Ursa Major. It was only as optical equipment and astronomical understanding improved that it became clear that this nebulous region was really a galaxy outside our own galaxy. What an incredible epiphany that must have been, to realise that the universe is not confined to our own surroundings, but extends far out into space. I always wonder: how far?!

 

1200806693_M81-LHaRGB-Method-06-Flat.thumb.png.ff74207ad5aad0ab75abb9d0aa6e71f0.png

 

Technical Details

Celestron EdgeHD 8" with 0.7x reducer, QSI 683-WSG8 with Astrodon 31mm filters, Mesu 200

L = 32 x 1200s
RGB = 18 x 600s
Ha = 14 x 1800s
Total = 26 hours 40 minutes

All in all I am happy with the outcome of this one. Collimation of the Edge 8" is an issue and the stars have suffered as a consequence. I just couldn't tame the big'uns and there is some significant chromatic aberration, but I can just about accept it. That Esprit 150ED is looking ever tastier! The mount is just a superstar and has done a fabulous job of keeping the scope on target. Seeing is always pretty pants I have now discovered, so results are never going to be perfect. That remote observatory in Spain is looking ever tastier! The detail in the galaxy and in some of the background, including M81's satellite galaxy, the dwarf irregular galaxy Holmberg IX, looks pretty good. This is definitely down to better tracking and guiding by the Mesu over my old HEQ5. What can I do to improve on this, apart from a new telescope and a new location? Please let me know your suggestions...

Thanks for looking and clear skies to you all!

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Marvellous image Gav, I did this a few weeks ago through my Esprit 150 and posted it on here so that’ll give you and idea of what a change of scope will give you.   Other than that my only suggestion would be move to Spain..  been thinking about that myself. 

Dave 

 

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10 minutes ago, Laurin Dave said:

Marvellous image Gav, I did this a few weeks ago through my Esprit 150 and posted it on here so that’ll give you and idea of what a change of scope will give you.   Other than that my only suggestion would be move to Spain..  been thinking about that myself.

Just revisited your image of M81 & M82 with the Esprit 150 and I definitely prefer your stars! I do like the focal length that the Edge 8" offers though... I will just have to work on perfecting the set up and probably the processing to tame those stars! And also get a 150, just to see, you know, give it a try, you can never have too many scopes!!! ? Oh, and yes, see you in Spain! Though in reality I have always thought that I will go and live in the Tuscan hills of Italy one day...

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22 minutes ago, teoria_del_big_bang said:

Very nice image and a great introduction to it ?   :thumbright:

Steve

Thank you Steve.

9 minutes ago, DAVE AMENDALL said:

That's a great image.!!!. I have looked for M81 a number of times with my C8 and properly set up synscan and never even seen it under semi urban skies. Yes Spain is the answer and not for just Astronomy either.................Dave

Thank you Dave. I showed it to a group at a local school I was doing an astronomy evening with last week through a Celestron 8" and when I said that the faint fuzzy smudge with a bright core that they could see was a galaxy 12 million light years away, they were all just flabbergasted, parents, pupils and teachers alike! I do love a bit of visual astronomy! The skies were large rural town, so not awful, but not that great. Keep hunting and you will find it - even more likely if you head out to a dark sky site. Good luck!

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1 hour ago, Saganite said:

Superb image as always Gav. The two Galaxies M81 & M82 are always visited whenever I use my Dob. :smiley:

Thank you Steve. I am about to embark on restoring an old and unloved 12" Revelation dob that is currently standing in a corner at my local observatory, without a base... If successful, I will certainly be aiming it towards Bode's Nebulae!

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2 minutes ago, Saganite said:

Always a joy to witness a good telescope given a second lease of life, so be sure to post pictures for us all ! :smiley:

Good shout... I will do some before and after pics. The tube is currently home to a plethora of spiders and the mirror is their graveyard... ?

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Gav

That is a very good image. 

On the subject of the stars and CA - you can easily compensate for this in post processing. If you use PS, then I'd suggest you use this Adam Block technique - take the smudge tool and set the mode for colour at a strength of 25%. Use this to adjust the halos or any offending star colours. This allows you to smear the colour without impacting detail. 

(If you are interested in a star comparison with the Esprit 150,  my M81 image is within my album Deep Sky III).

Alan 

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2 hours ago, alan4908 said:

Gav

That is a very good image. 

On the subject of the stars and CA - you can easily compensate for this in post processing. If you use PS, then I'd suggest you use this Adam Block technique - take the smudge tool and set the mode for colour at a strength of 25%. Use this to adjust the halos or any offending star colours. This allows you to smear the colour without impacting detail. 

(If you are interested in a star comparison with the Esprit 150,  my M81 image is within my album Deep Sky III).

Alan 

Thanks Alan. Excellent, I will investigate the Block Smudge Technique. As for your Esprit 150 images, you are definitely partly responsible for my interest in that scope!

47 minutes ago, MartinB said:

Excellent M81 Gave and you've picked out the Ha regions very nicely

Thank you Martin. 

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Great image and write up, good detail and the Ha regions are spectacular.

And a nice tiny distant galaxy captured in the lower left quadrant, I’m going to be disappointed if I can’t find at least one of these in your image posts.?

The Esprit 150 is a great scope, I’m just a little frustrated with the FOV with the KAF 8300 sensor for the smaller galaxies, it looks like an Atik 460 or equivalent is required as the the 428 is now discontinued. I’m experimenting with a little ASI 120 mm camera at the moment and the concept of ‘lucky imaging’ a la planetary imaging,  but this is well outside my CCD comfort zone.

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Wow, this is spectacular. I've been working hard toward collecting data on M81 and M82 but one thing after another is getting in the way. I've got my scope trained on them both as I write this, to add to the few hours data so far in this latest attempt, but a quick glance outside moments ago has revealed a thin layer of patchy cloud overhead. Your photo, at the very least, will help keep me 'focused' on this pastime. 26 hours?! The way it's going, I have many long days ahead of me to get anywhere near this kind of data. Beautifully done!

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9 hours ago, tomato said:

Great image and write up, good detail and the Ha regions are spectacular.

And a nice tiny distant galaxy captured in the lower left quadrant, I’m going to be disappointed if I can’t find at least one of these in your image posts.?

The Esprit 150 is a great scope, I’m just a little frustrated with the FOV with the KAF 8300 sensor for the smaller galaxies, it looks like an Atik 460 or equivalent is required as the the 428 is now discontinued. I’m experimenting with a little ASI 120 mm camera at the moment and the concept of ‘lucky imaging’ a la planetary imaging,  but this is well outside my CCD comfort zone.

Thank you mr tomato! Hah! Those tiny distant fuzzies, yes, there are a few scattered around the background. I tried to identify the one you spotted - the best I could do was the ‘larger’ one just left of centre near the bottom of the field of view. It is PGC 28505, a mag +15.6 elliptical galaxy, 550 million light years away!

Interesting what you say about the 8300 and 150 fov - I noticed that Alan is using an SX-814 with smaller pixels. That combo certainly seems to work well. Unfortunately I am unlikely to be purchasing a new scope and a new camera any time soon!! The Edge is looking perfectly acceptable all of a sudden!!!

4 hours ago, Seanelly said:

Wow, this is spectacular. I've been working hard toward collecting data on M81 and M82 but one thing after another is getting in the way. I've got my scope trained on them both as I write this, to add to the few hours data so far in this latest attempt, but a quick glance outside moments ago has revealed a thin layer of patchy cloud overhead. Your photo, at the very least, will help keep me 'focused' on this pastime. 26 hours?! The way it's going, I have many long days ahead of me to get anywhere near this kind of data. Beautifully done!

Thank you. Astrophotography is ridiculously frustrating isn’t it. Patience is the key, that’s for sure. I’m just glad I’m not having to work to deadlines with this! Good luck with your data collection and I look forward to seeing the resulting image, eventually. 

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4 hours ago, PhotoGav said:

 

Interesting what you say about the 8300 and 150 fov - I noticed that Alan is using an SX-814 with smaller pixels. That combo certainly seems to work well. Unfortunately I am unlikely to be purchasing a new scope and a new camera any time soon!! The Edge is looking perfectly acceptable all of a sudden!!! 

 

Yes, I think the Atik 460 and SX-814 have the same FOV with the 814 having the smaller pixels, which might be pushing it a bit for a Westerly UK sky. I will be going for one of these if my toe dip into the CMOS pool doesn't take me any further in that direction.

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1 hour ago, tomato said:

Yes, I think the Atik 460 and SX-814 have the same FOV with the 814 having the smaller pixels, which might be pushing it a bit for a Westerly UK sky. I will be going for one of these if my toe dip into the CMOS pool doesn't take me any further in that direction.

I will be following your progress with great interest...

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Excellent image Gav. Very well imaged and processed ? ? ?.

You are right about the top-left corner and collimation but it certainly does not detract excessively from your very fine image.

I am thoroughly biased when it comes to refractors and the simplicity they bring to an otherwise complicated AP hobby.  As well as operating at F7, there are imagers who are using reducers with great success on the Esprit 150 too.  I have also found (after a brief flirtation with an Atik One 9.0 at home on my WO 132FLT) that a cropped 8300 image produces results that 'approach' the higher resolution of the two Sony chips (eg like the Atik 460 or 490) and I have found for UK skies this to be a good wallet-forgiving compromise.

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24 minutes ago, Barry-Wilson said:

Excellent image Gav. Very well imaged and processed ? ? ?.

You are right about the top-right corner and collimation but it certainly does not detract excessively from your very fine image.

I am thoroughly biased when it comes to refractors and the simplicity they bring to an otherwise complicated AP hobby.  As well as operating at F7, there are imagers who are using reducers with great success on the Esprit 150 too.  I have also found (after a brief flirtation with an Atik One 9.0 at home on my WO 132FLT) that a cropped 8300 image produces results that 'approach' the higher resolution of the two Sony chips (eg like the Atik 460 or 490) and I have found for UK skies this to be a good wallet-forgiving compromise.

Blimey, best not to show this post to the Financial Director, or that will be the Atik 460 off the shopping list...☺️

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Agree with all the comments, Gav - a very fine image, well done.

23 hours ago, alan4908 said:

Gav

That is a very good image. 

On the subject of the stars and CA - you can easily compensate for this in post processing. If you use PS, then I'd suggest you use this Adam Block technique - take the smudge tool and set the mode for colour at a strength of 25%. Use this to adjust the halos or any offending star colours. This allows you to smear the colour without impacting detail. 

(If you are interested in a star comparison with the Esprit 150,  my M81 image is within my album Deep Sky III).

Alan 

Thanks for posting that Alan.  I've had the same issues in some of my images with an 11" EdgeHD - I may go back to a couple of them and give this a try,

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3 hours ago, Barry-Wilson said:

Excellent image Gav. Very well imaged and processed ? ? ?.

You are right about the top-left corner and collimation but it certainly does not detract excessively from your very fine image.

I am thoroughly biased when it comes to refractors and the simplicity they bring to an otherwise complicated AP hobby.  As well as operating at F7, there are imagers who are using reducers with great success on the Esprit 150 too.  I have also found (after a brief flirtation with an Atik One 9.0 at home on my WO 132FLT) that a cropped 8300 image produces results that 'approach' the higher resolution of the two Sony chips (eg like the Atik 460 or 490) and I have found for UK skies this to be a good wallet-forgiving compromise.

Thank you Barry, and coming from today’s APOD imager - extra special! Congratulations on the APOD, your Spanish output is worthy of APOD every day!

I’m very interested to read your thoughts about the 8300 with the 150 frac. Definitely on my ‘one day’ list!

1 hour ago, x6gas said:

Agree with all the comments, Gav - a very fine image, well done.

Thank you Mr. Gas!

32 minutes ago, Pompey Monkey said:

That is an absolutely superb image. Thank you for sharing it! :)

Thank you Paul.

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