M101 The Pinwheel Galaxy & NGC5474

[Barry-Wilson]

I've really enjoyed processing this image with quality data from good transparency and no moon.  The last couple of months I've been able to cool my ccd to -20degC without any condensation forming on the reducer and the images are quieter for it too.  The moist air streams last autumn played havoc with the reducer (on the FSQ as well as WO) the and the efficient cooling of the QSI, however, I think running my de-humidifier for an hour at dawn and an hour early evening (with a simple timer plug) and adding 4 additional vents just under the eaves soffit and gable of the observatory roof, really helped.  Just contemplating whether to capture some Ha to enhance the HII regions for which M101's spiral arms are a good example.

Looking at web images of M101 as a reference, it is appears quite tempting to over sharpen to try and enhance the arms and their dust lanes.  This is striking at scales less than 1.00"/px with long FL scopes, but I have resisted doing this at my modest 1.47"/px, but now as I type I'm not sure whether I should push the core further?

Details:

• WO FLT132 at F5.6
• QSI 683-wsg with OAG
• Avalon Linear FR
• Astrodon filters
• 12 x 600s Lum; 12 x 300s each RGB - all sunbs bin 1; 5 hours total integration
• SGPro and PixInsight

Thanks for looking and C&Cs always welcome.

[gnomus]

Really nice Barry - as ever.  Lovely clean and flat background and terrific colours.  I'm struggling a little for targets right now with my 352 f/l.  I may need to get something a little longer.....

[Barry-Wilson]

Thanks Steve.  A flat background is helped using PI's Multiscale Median Transform with a mask to protect the high signal areas (eg galaxy or DSO).  There is a great tutorial contrasting (& complementing) PI and PS processes on The Astro Imaging Channel, tutorial, which I recommend if you haven't already seen it.

Just boosted curves to lift the colour a touch more in the galaxy, revised image.

Yes, a longer FL would be nice and I've been googling RCs and Dall Kirkhams.  I can't complain though .

[gnomus]

Thanks Barry I'll take a look at that video.  I'm not sure I follow whatbyou are saying about MMT - are you using this for noise reduction or to remove remaining (post DBE) gradients?

[derrickf]

Great image Barry, I always find your processing very pleasing - no garish colours and false detail (aka processing artefacts masquerading as detail) in your images.

 

Derrick

[Barry-Wilson]

Thank you Derrick for the kind words.  I try hard to only process to the limits of my data and am very conscious of the ease with which PI processes can overwhelm. Not too sure I always succeed however your words reassure me.

1 hour ago, gnomus said:

Thanks Barry I'll take a look at that video.  I'm not sure I follow whatbyou are saying about MMT - are you using this for noise reduction or to remove remaining (post DBE) gradients?

Steve you're right and MMT is primarily used for NR - and it does a remarkable job at taming the background and leaving the detail in the galaxy/DSO untouched - I find it does benefit smoothing any remnant gradient too.  In the TAIC tutorial David Ault gives a good demo of MMT.

I know it's a shameless egotistical plug , but I am adding PI tutorials to my smugmug site (I've got a way to go to beat Harry's or Kayron's), two done and I have more planned when I can find the time.  I'm sure you know how it is!

[swag72]

Nice one Barry - Very soft and subtle

[Barry-Wilson]

Thanks Sara . . . I try to go for the 'Andrex' feel, LOL .

Hope you're progressing with the Mesu - really looking forward to seeing your first set of results.

[ollypenrice]

Indeed it is very fine and doesn't have the pseudo-detail Derrick mentions. I like the framing, too, with the little companion whose number I've forgotten.

Ha might add a little crackle here and there. There's nothing much to resolve in it at this FL so you can be heavy on the NR and still use it effectively.

Olly

[Barry-Wilson]

Thanks Olly for your encouragement.

[gnomus]

28 minutes ago, Barry-Wilson said:

Thanks Sara . . . I try to go for the 'Andrex' feel, LOL .

Hope you're progressing with the Mesu - really looking forward to seeing your first set of results.

I feel that my images achieve the 'Andrex' feel too..... the only difference being that you are achieving the 'unused' Andrex look, whereas............

[Ruud]

A wonderful image! Beautifully recorded and processed. Very intricate and detailed. NGC 5477 is there too, looking like a baby starfish.

Excellent!

[laudropb]

Very nice image.

[swag72]

12 hours ago, Barry-Wilson said:

Thanks Sara . . . I try to go for the 'Andrex' feel, LOL .

Hope you're progressing with the Mesu - really looking forward to seeing your first set of results.

The Mesu is doing just fine thanks Barry - Infact I have forgotten that it's there! 

Interesting to see this M101 as I'm looking at it now with the ODK10 and it's a total frame filler - If I get what I want, it won't even fit

[toxic]

oh Barry that is very nice indeed,colour detail and ballence it has it all.

 

[Barry-Wilson]

Thanks for the comments Ruud, laudropb and Chris.

[Petergoodhew]

That's a stunner Barry. Will have a go at M101 next time the clouds part (hopefully before Halley's comet returns!)

I'm still having obsy roof problems - it got stuck open twice while I was away in France the week before last, and I had to get the neighbours out of bed to close it manually.  Have ordered photoelectric sensors to replace the reed switch, and developed a gizmo to force roof closure when I'm remote. 

[Barry-Wilson]

Thanks Peter.

Sorry to read about your on going roof woes.

[Pompey Monkey]

Not too shabby at all

I really like the colours too.

[Fay]

Really like it Barry. very subtle, great star colour and framing, smooth......i could go on

 

Fay

[Barry-Wilson]

Cheers Paul and Fay: the WO FLT132 is performing well and is a pleasure to use.