M74 - The Phantom Galaxy

[PhotoGav]

This is a data set that was captured during September and October last year that I have finally got round to processing. The target is Messier 74, The Phantom Galaxy. It is a Grand Design spiral galaxy about 30 million light years from Earth in the constellation of Pisces. It has an apparent magnitude of about +10 and has the second lowest surface brightness of all the Messier objects (the lowest is M101). This makes it difficult to observe visually, hence the name! After many hours of imaging, this is what it looks like to me. One of the things I particularly like with this image are all the little galaxies surrounding M74, especially to the right hand side. I'm struggling to identify them with great certainty, but Sky Safari is telling me that the majority of them are in the region of 2 billion light years away - can that really be true?!

 

 

Technical Details

Celestron EdgeHD 8" and QSI 683-WSG8 with 31mm Astrodon filters, all on a Mesu 200 mount

B = 19 x 600s
R & G = 13 x 600s
L = 50 x 1200s
Ha = 15 x 1800s
Total Integration Time = 31 hours 40 minutes

I didn't set out to capture that much data, but that is what I ended up with! I'm very happy with the detail that all that luminance has brought to the image. As I make each upgrade, so something else becomes the reason why the image is not as good as it could be. I still wonder about the Celestron Edge as an imaging scope - it's not bad, but the stars are pretty ugly (spherical aberration apparently). I'm happy to make that trade off to get the 2032 mm focal length, for now. Unfortunately, the biggest issue I keep coming up against is my local sky quality (and that's when I can see the sky, let's not talk about cloud right now...!). Even that's not too bad, but I know it could be better. Oh well, again, trade offs - I'm working on my crowd funding appeal to launch an imaging satellite along with all the Elon Musk satellites (but let's not talk about StarLink right now...!).

All the data was calibrated, stacked and combined in Astro Pixel Processor. The finishing touches were applied in PhotoShop.

I hope you like the image, all comments greatly received.

[Davey-T]

Nicely done Gav, another one of those targets I've gathered data on with the 10"SCT when able but not processed, I did try it  as a first project in APP but couldn't get past an issue with the flats and never got back to it.

Dave

[ollypenrice]

A classic face-on spiral, indeed. Nice one.

Olly

[PhotoGav]

Thank you Dave, thank you Olly! I could never understand how people didn't process their data straight away and now I find myself in that category of hoarders for the future!

[tomato]

Great image, not so frequently captured as the very similar looking M101, probably due to it’s smaller size.
 

It’s on my list to image with my small galaxy set up when autumn rolls around, and if we ever get any respite from cyclones with nice names (or should they be called depressions because that’s what they make me...)

 

[PhotoGav]

Thank you @tomato - no doubt the Deep Sky West (Midlands) will do this target justice when you get to it! If the Depressions ever let you...

[astro mick]

A really good image of M74,i regard this as a difficult object.

Mick.

[Laurin Dave]

Nice one Gav...  what news on your camera?

Dave

[PhotoGav]

2 hours ago, astro mick said:

A really good image of M74,i regard this as a difficult object.

Mick.

Thank you Mick. It is a tricky customer, it took me several attempts to get a process that I was happy with. Still not totally convinced - it’s gone a bit pinky in the middle!

2 hours ago, Laurin Dave said:

Nice one Gav...  what news on your camera?

Dave

Thanks Dave. QSI have been great and very responsive. They suggested that I send the camera in for repair. I can’t face being without my baby and while the weather is cold, the cooling is working fine. They are going to send me two replacement fans for me to swap out. Hopefully that will work and all will be good. If not, I will have to send it in... Fingers crossed!

[Whistlin Bob]

That's a beauty! A great reward for so many hours spent. I especially like the strong Ha signal that you've captured- it really lifts the whole image.

I'm always slightly bemused by the category 'Grand Design' and what the name seems to imply- does anyone know the origins of it? Am I reading something into it that I shouldn't?

[PhotoGav]

Thank you @Whistlin Bob.

As for the term grand design spiral galaxy and its origins, I have this for you:

The term can be traced back to the theoretical work of C.C.Lin in explaining the spirals as due to density waves in galactic discs.

A paper from 1970 discusses the "Existence of 'Grand Design'". Note the use of "scare quotes", suggesting that the term was new and would not be widely recognised by his readers.

Chia-Chiao Lin was an important Chinese/American Mathematician. It is reasonable to believe that the term was coined by him or one of the mathematicians that he worked with at MIT. And was in use since about 1964, when the first of a series of papers "On the structure of Spiral Galaxies" was published.
 

[bob-c]

Nice work Gav.

Bob.

[alan potts]

Superb shot Gav, 31 hours, that more than 10 times what I spend on an image, may well account why I'm not in your class.

Alan

[PhotoGav]

On 27/02/2020 at 14:50, bob-c said:

Nice work Gav.

Bob.

Thank you Bob.

9 hours ago, alan potts said:

Superb shot Gav, 31 hours, that more than 10 times what I spend on an image, may well account why I'm not in your class.

Alan

Thank you Alan. I am yet to find the point at which I have too much data for one image! The more you collect the easier it is to process and the better the result. I’m down to one image per New Moon, if the weather allows. I was out showing one of my GCSE pupils how to do astrophotography recently and we took one 60 second frame of six different objects. Quite a different approach! The shriek of delight when the image of M42 popped up on the camera back was priceless!

[alan potts]

22 hours ago, PhotoGav said:

Thank you Bob.

Thank you Alan. I am yet to find the point at which I have too much data for one image! The more you collect the easier it is to process and the better the result. I’m down to one image per New Moon, if the weather allows. I was out showing one of my GCSE pupils how to do astrophotography recently and we took one 60 second frame of six different objects. Quite a different approach! The shriek of delight when the image of M42 popped up on the camera back was priceless!

I am sure you are absolutely correct about lots of data making processing easier, I have sort of found that out myself using PS when I have just got 1 hour and other times when I have 3 hours. I think once I am a bit more into AP and sort of done a year I will add to various targets and re-process them, I never dump data unless it's rubbish.

Alan

[geoflewis]

That's a superb version Gav and worthy of the time that you put into it; it really sparkles with the Ha regions showing really well. I've only imaged it once, grabbing less than 3 hours data, mostly L with just 30 mins (3x10m) each RGB and it showed, with the result being almost devoid of colour. Seeing yours I really need to have another try at it.

[Ruud]

Bravo! It's a beauty.

[PhotoGav]

On 03/03/2020 at 11:10, geoflewis said:

That's a superb version Gav and worthy of the time that you put into it; it really sparkles with the Ha regions showing really well. I've only imaged it once, grabbing less than 3 hours data, mostly L with just 30 mins (3x10m) each RGB and it showed, with the result being almost devoid of colour. Seeing yours I really need to have another try at it.

Thanks Geof. Good luck with your next attempt. There's no substitute for volume of half decent data!

On 03/03/2020 at 11:24, Ruud said:

Bravo! It's a beauty.

Thank you Ruud.

[Rodd]

One of the best galaxy images I have seen.  realistic par exellance

Rodd

[PhotoGav]

4 minutes ago, Rodd said:

One of the best galaxy images I have seen.  realistic par exellance

Rodd

Thank you Rodd!

[Rodd]

1 minute ago, PhotoGav said:

Thank you Rodd!

It makes me take a look at the palette philosophy.  there are colors there--but they are very faint (other than the ha).  But vibrant as well.  I tend to over do the palette.  make blue galaxies too blue.  This one is a good example of how to process color, I think.  Any tips?

Rodd

[PhotoGav]

14 minutes ago, Rodd said:

It makes me take a look at the palette philosophy.  there are colors there--but they are very faint (other than the ha).  But vibrant as well.  I tend to over do the palette.  make blue galaxies too blue.  This one is a good example of how to process color, I think.  Any tips?

Rodd

Interesting Rodd, thank you. Ultimately it is just personal taste. My taste happens to be to remain ‘faithful’ to the data I collect and use saturation techniques to avoid too much colour loss rather than to pump the colour up to eyeball watering levels! I firmly believe that with processing, less is more, unlike with data collection! I really like APP and Photoshop, they allow the data to be presented without too much cooking.

Meanwhile, other viewers will think that this image lacks punch and colour!

[Rodd]

4 minutes ago, PhotoGav said:

Interesting Rodd, thank you. Ultimately it is just personal taste. My taste happens to be to remain ‘faithful’ to the data I collect and use saturation techniques to avoid too much colour loss rather than to pump the colour up to eyeball watering levels! I firmly believe that with processing, less is more, unlike with data collection! I really like APP and Photoshop, they allow the data to be presented without too much cooking.

Meanwhile, other viewers will think that this image lacks punch and colour!

I was mostly referring to my NGC 3184--still on page 1 I think.  I wouldn't say the blue is eye watering....I don't think anyway...but it definitely is miles beyond yours, and unnecessarily so.  There could be a difference in native color in the two galaxies--but I do not think that is the case.  Palette was one of the reasons for my unhappiness with the image.    But, and here is the kicker--its more than just not having too much color, because if I de saturate the galaxy--it looks like a gray blob---yours looks......"real" is the best term that comes to mind

Rodd