Cepheus to Cygnus, 57 panel mosaic.

[ollypenrice]

Our largest mosaic to date. Capture, pre-processing and construction by Paul Kummer using gear jointly owned by Paul, myself and Peter Woods. (Avalon M Uno, Samyang 135 wide open at F2, TS 2600 OSC CMOS camera. My post processing. I gently gently enhanced ten extensive regions of interest using existing telescopic images but only the nebulosity was enhanced. All stars are Samyang, for consistency.

Paul's construction of the linear data was outstanding and this was remarkably easy to process.

I do like finding out unexpected relationships between well-know objects and also seeing their relative sizes. The North America, for instance, is smaller than I thought.

The target per panel was 21x3 minute subs, captured between Aug 21st and Sept 23 this year. Stacking was in super pixel and then downsized to 80%.

Larger verison here.  https://ollypenrice.smugmug.com/Other/Emission-Nebulae/i-TL48wrC/A

Olly

 

[powerlord]

that is truly one to be proud of. I'd love to see the full resolution version. You should get it printed 300cm wide or something for a wall!

stu

[tooth_dr]

Incredible!  I enjoyed looking around the larger version, seeing all the targets I've recently imaged and their spacial and size relationship to one another.

Edited September 28, 2023 by tooth_dr

[tomato]

Amazing, you surely must go on and fill in  rest of your hemisphere (as and when). 

How are you coping with projection effects? I seem to recall APP does something clever with these but I have never come close to doing a big enough area of sky to worry about them.

 

 

[ollypenrice]

23 minutes ago, tomato said:

Amazing, you surely must go on and fill in  rest of your hemisphere (as and when). 

How are you coping with projection effects? I seem to recall APP does something clever with these but I have never come close to doing a big enough area of sky to worry about them.

 

 

It's put together in APP which is very clever with the geometry.

 

32 minutes ago, powerlord said:

that is truly one to be proud of. I'd love to see the full resolution version. You should get it printed 300cm wide or something for a wall!

stu

The printer's running as I type.  My largest option is 'extended A3' but I'm thinking of joining two A3s together. I no longer have a friendly neighbourhood printer with a roll paper machine, unfortunately. He's retired.

Olly

[vlaiv]

49 minutes ago, ollypenrice said:

I do like finding out unexpected relationships between well-know objects and also seeing their relative sizes. The North America, for instance, is smaller than I thought.

Do be careful with such assertions.

You have a lot of sky covered in such mosaic and there must be some level of distortion present when you project large part of sphere onto a flat plane.

One of projections used has a consequence of enlarging objects that are close to the edge versus those that are in center.

This is well known in map of the world vs globe for size of landmasses (for example Svalbard looks larger than Madagascar on google maps - but in reality it is only 1/3 of the size - ~1500km vs ~500km)

[sinbad40]

That is some fantastic work by all, from the imaging to the processing.  I have to agree with Stu, it would be worth seeing if it can be put onto a large format for the wall.

[WolfieGlos]

Got to be an APOD, surely. Stunning work Olly.

We have A0 plotters at work, I can only imagine the ink usage and the bosses reaction 🤣

[AstroMuni]

1 hour ago, ollypenrice said:

I do like finding out unexpected relationships between well-know objects and also seeing their relative sizes.

Its a lovely view of our galaxy and its interesting to see that at this scale its dominated with reds and browns interjected with blues. Hats off to you & your friends for compiling this.

[ollypenrice]

17 minutes ago, vlaiv said:

Do be careful with such assertions.

You have a lot of sky covered in such mosaic and there must be some level of distortion present when you project large part of sphere onto a flat plane.

One of projections used has a consequence of enlarging objects that are close to the edge versus those that are in center.

This is well known in map of the world vs globe for size of landmasses (for example Svalbard looks larger than Madagascar on google maps - but in reality it is only 1/3 of the size - ~1500km vs ~500km)

I realize that there are such distortions, inevitably, but I was only speaking approximatively.

Olly

[Laurin Dave]

Fabulous image Olly... 57 panlels and all data collected in just over a month, makes us here in the UK just a trifle jealous!

Dave

[powerlord]

30 minutes ago, ollypenrice said:

It's put together in APP which is very clever with the geometry.

 

The printer's running as I type.  My largest option is 'extended A3' but I'm thinking of joining two A3s together. I no longer have a friendly neighbourhood printer with a roll paper machine, unfortunately. He's retired.

Olly

I was thinking more a professional print - gotta be worth it!

[glafnazur]

That is truly awesome Olly. 

[Mr Spock]

Quite spectacular 👍

[The Lazy Astronomer]

My, oh my!

 

 

That's it, I've no other words!

[saac]

And people ask "why do you do that" . Well done @ollypenrice, that seems wholly inadequate but then so would anything else I could think in its stead.  Well done to all involved, the large image is just breathtaking. 

Jim 

Edited September 28, 2023 by saac

[Gerr]

Bravo. An utterly marvellous mosaic.  

[B4silio]

Nom de bleu que c'est beau!

Fantastic work, and surprisingly little integration time overall (~60h all told?) That F2 is definitely doing its work!

[symmetal]

Well done to all involved on such a large endeavour, but can I ask what happened to the Milky Way stars? On the large image the background stars are all pretty much the same size and brightness, and there's no change in star density throughout the whole image. 🤔

Alan

[ollypenrice]

9 hours ago, symmetal said:

Well done to all involved on such a large endeavour, but can I ask what happened to the Milky Way stars? On the large image the background stars are all pretty much the same size and brightness, and there's no change in star density throughout the whole image. 🤔

Alan

Interesting question. The stars have been given an absolutely bog-standard log stretch using the mid point slider in Ps Levels, so the size/brightness range should be perfectly normal and typical of most astrophotos. (Indeed, since there has been no star reduction*, it should be a classic AP stretch.)  However, the stretch itself was much lighter than that given to the background. If  you use one stretch for all you end up with this:

Now some people might like or prefer this and, as an image demonstrating the richness of the MW starfield, it's fine. It's just not what our image is about. Modern processing allows a telescopic look to be extracted from a lens image, meaning smaller stars and more visible nebulosity.

A consequence of the separate stellar stretch is that small/faint stars will not reach the level of the widespread nebulosity and will remain invisible, so diminishing the range of the stars we can see. This is exaggerated when faint nebulosity is lifted well clear of the background sky but, again, that is the whole point of an image like this. Perhaps this accounts for what you are seeing?

Olly

*By star reduction I mean the reverse-processing of a star of a given size to make it smaller. Our stars have simply never been stretched far enough in the first place to need it.

 

[aleixandrus]

Oh god, you made my mosaic bite the dust! Impressive work. I'll save that image (for personal use) as a map of that region of the sky. Love it!

 

[ollypenrice]

12 minutes ago, aleixandrus said:

Oh god, you made my mosaic bite the dust! Impressive work. I'll save that image (for personal use) as a map of that region of the sky. Love it!

 

No, yours is a great image - as I said at the time and repeat here.

Olly

[simmo39]

No expert but this is fantastic, go big or go home!

[Bluesboystig]

This is an absolute masterpiece. Total awe!

[carastro]

O….M….G

57 panels!!!!!!!!!!!  
 

amazing.  
 

NB. It is projects like this that put everything into perspective.   I never realised that NGC7822 was THAT large.
 

 Well done to you and the team.  Hope this is going on Astrobin.  
 

Carole

Edited September 29, 2023 by carastro