M13 from DSW

[gnomus]

This is a series of 10 minute and 60 second LRGB subs from the Deep Sky West facility in New Mexico. Processing was done mostly in PI, but PS was used for final tweaking.  You may need to click the full size image to see the 'propeller'.

• Luminance: 35x60" bin 1x1
• Luminance: 11x600" bin 1x1
• Red: 12x60" bin 1x1
• Red: 20x600" bin 1x1
• Green: 12x60" bin 1x1
• Green: 20x600" bin 1x1
• Blue: 12x60" bin 1x1
• Blue: 20x600" bin 1x1

Which I think makes exactly 13 hours.

Tak FSQ 106; Paramount MyT; QSI 683; Astrodon Filters

 

[Knighty2112]

Well done. Can make out the propeller well in the normal image too.  

[gnomus]

7 hours ago, Knighty2112 said:

Well done. Can make out the propeller well in the normal image too.  

@MrsGnomus insists that she can see two propellers.  (And she hasn't had any gin yet.)

[Knighty2112]

1 hour ago, gnomus said:

@MrsGnomus insists that she can see two propellers.  (And she hasn't had any gin yet.)

Actually, zooming in on the image to the left of the main large propeller in the centre of the bright part of the glob, there is a smaller structure that looks like a smaller propellor too! Well spotted Mrs Gnomus!  

[gnomus]

3 minutes ago, Knighty2112 said:

Actually, zooming in on the image to the left of the main large propeller in the centre of the bright part of the glob, there is a smaller structure that looks like a smaller propellor too! Well spotted Mrs Gnomus!  

That is exactly what she is seeing (and what I also see).  It is orientated 180 degrees compared to the main one.

[ollypenrice]

That's a splendid result. First off, those absolute essentials - background sky and starfield - are firmly in place. Then the globular is blazing away with convincing star colour. OK, I think a tad more contrast towards the core woud guild the lilly, but this is a winner.

How did you blend the sub lengths? I've never tried that on M13. It makes sense though.

Olly

[gnomus]

6 hours ago, ollypenrice said:

That's a splendid result. First off, those absolute essentials - background sky and starfield - are firmly in place. Then the globular is blazing away with convincing star colour. OK, I think a tad more contrast towards the core woud guild the lilly, but this is a winner.

How did you blend the sub lengths? I've never tried that on M13. It makes sense though.

Olly

Thanks Olly.  Sub lengths were blended using PixInsight's HDRComposition Process followed by HDRMutiscaleTransform.  Different settings in this last process allows for different levels of detail/contrast to emerge and these were blended together in PS - I use a mask but the 'Eraser' method should also work.

This has a 'bit' more contrast - let me know if my 'bit' equals your 'tad'.

[ollypenrice]

2 hours ago, gnomus said:

Thanks Olly.  Sub lengths were blended using PixInsight's HDRComposition Process followed by HDRMutiscaleTransform.  Different settings in this last process allows for different levels of detail/contrast to emerge and these were blended together in PS - I use a mask but the 'Eraser' method should also work.

This has a 'bit' more contrast - let me know if my 'bit' equals your 'tad'.

Looks very much as if one English Bit = 1 European Tad!

We now get into a problematic processing subtlety, which is that the presentation size impacts upon the processing decisions. If showing this at the smaller size as on the thread, I'd go for slightly more core contrast but for the full size I'd say it was perfect.

The blending is very seamless and natural. There is an excellent separation between red and blue stars.

(I often wonder why M13 has so many blue stars in pictures. It is at odds with what they tell us about globulars in the text books, which describe a cut-off point on the HR diagram main sequence above which there are no hot stars. Most HR diagrams for globulars have a small concentration of white dwarves, which can be blue, off the main sequence in the upper left but M13 really does seem to be blue-dominated, even in the Hubbe image.)

Olly

[gnomus]

4 minutes ago, ollypenrice said:

Looks very much as if one English Bit = 1 European Tad!

We now get into a problematic processing subtlety, which is that the presentation size impacts upon the processing decisions. If showing this at the smaller size as on the thread, I'd go for slightly more core contrast but for the full size I'd say it was perfect.

The blending is very seamless and natural. There is an excellent separation between red and blue stars.

(I often wonder why M13 has so many blue stars in pictures. It is at odds with what they tell us about globulars in the text books, which describe a cut-off point on the HR diagram main sequence above which there are no hot stars. Most HR diagrams for globulars have a small concentration of white dwarves, which can be blue, off the main sequence in the upper left but M13 really does seem to be blue-dominated, even in the Hubbe image.)

Olly

It may interest you to know that the English 'bit' is itself derived from the Scottish 'thochty'.  Whether the 'bit' will hold to the 'thochty-standard' post IndyRef2 remains to be seen.

(Incidentally, Olly, 'guild the lily'?  And you an English teacher!  You been hitting the Japanese whisky again?)

[ollypenrice]

15 minutes ago, gnomus said:

It may interest you to know that the English 'bit' is itself derived from the Scottish 'thochty'.  Whether the 'bit' will hold to the 'thochty-standard' post IndyRef2 remains to be seen.

(Incidentally, Olly, 'guild the lily'?  And you an English teacher!  You been hitting the Japanese whisky again?)

Oh dear. gild. My excuse is that I have been down with the vilest bronchial infection which has had me all but wiped out for four weeks now. My head is a mush. It is just starting to clear up. My step daughter manages a sheltered housing establishment and she cheerfully told me that, all over France, the elderly are being carried off by this thing. I reminded her that I am elderly... But I'm clinging on by the skin of my Horlicks.

Olly

[Shibby]

That's lovely. Really nice range of natural star colours and fine, grainy field visible around the glob. To me, seems like a total nightmare combining different sub lengths on a target like this.