And yet another Iris...

[AndyUK]

I've really struggled with this one and even now I'm not happy about the noise considering the total integration time spent on this over 7 nights (25.5 hrs). It's almost certainly down to my dodgy processing, but 4 of these nights the transparency was atrocious and last night the wind was playing havoc with guiding... . So here's the details:

MN190, L 47 x 600s, R 60 x 240, G 105 x 240, B 125 x 240 (bias and flats applied). Stacked in DSS, processed in CS5 (inc Noise Ninja) and composite image merged in to bring detail back into the core.

Although it looks like the clear nights are going to continue, with the stiff breeze still about, I don't think I'm going to bother spending another night on this to get the Red channel up to 100+ subs - It seems to be a case of diminishing returns. As much as I love seeing other peoples images of these "dark" nebulae, I obviously don't have the knack of processing them

Any advise on how I can improve this / reduce the noise very gratefully received

[Gina]

Looks pretty good to me Maybe the core is a little burnt out. When you apply curves try to lift the middle but pull down a bit near the RHS, brighter part. That will boost the mid tones but hold back the brighter core. Hope that helps.

Here's my play with the image you posted.

[ollypenrice]

You have a big red-green gradient with red on the left. Using PIs SCNR or Rogelio's Hasta La Vista Green would help, as would DBE in Pixinsight. Do you have Gradient Xterminator? That might work as well.

To reduce noise in the colour I think you need longer colour subs.

A shorter still stretch for the core would help.

The dust is tough and a dark site makes a big, big difference.

Olly

[Martin-Devon]

Andy, thats a really nice Iris, although you seem to have a little "wash" of red & grainy-ness going on around the finer details. Are you using the reduce noise actions in Noel Carboni's or Annie's actions? I also find that the standard despeckle and reduce noise under the filter tabs of photoshop helps quite a bit as well.

[Quatermass]

Stunning Iris really nice.

[Daniel-K]

great job andy

[RikM]

I would run HLVG set to strong.

Make a duplicate layer for a highpass filter with radius of 5 pixels and set the blend mode to soft light, then apply a hide all mask and paint through to show the details you want to enhance.

Deepsky noise reduction from Noel's tools, run as new layer on top and adjust the opacity to suit.

It is still a wonderful image as it is Andy

[AndyUK]

Thanks very much everyone for the comments and advice - You know I honestly didn't notice that gradient at all when I was processing this, but as soon as Olly pointed it out it was glaringly obvious... I guess I couldn't see the wood for the trees...

Gina - I must admit, I wasn't too happy with that central star at all, and I did try to fiddle with it to make it look less like a white dot, but my various tweaks made it look even worse. I've never seen a curve shape like that before though - I'll have to have a play with it to see what impact it has when I use it...

Olly - I do indeed have HLVG and also Gradient Xterminator... I do also have PI LE for DBE, but I'm not sure how I'd go about using it on a nebula image (I've only ever previously used it on galaxy's and a couple of planetary nebulae).

I think possibly the biggest thing that's confusing me at the moment is guesstimating the length of subs to use . The reason I chose 240s was because I didn't want to oversaturate the core/stars - In a previous image I went for 10 mins and everything was completely blown away. Although too late for this particular image, what would you suggest as a starting point? I must admit, this is still in a very good place for me at the moment, but so are a few other things, and I've spent 7 nights on this already so although I'll still give this a reprocess (and tone down the core even more), as far as capture's concerned it looks as though I may as well write this version off and maybe come back to it next year, using more suitable length exposures...

Martin - I do have both Noels and Annie's actions, but I used Noise Ninja on this... However, I find that over use of denoising makes the resultant image look "plastic" (well, it does in my hands!). I did denoise the RGB as much as I could get away with... but that obviously wasn't enough

Rik - That's very useful information - Thanks! I frequently use a hidden layer mask hi pass filter, but I've never come across the "soft light" blend mode before (I think I've only ever used 4 of them out of the entire list ).

[Auntystatic]

Well I like it as it is cos its better than anything I've done so far, but there is some very helpful information being posted here, can not wait to see what you can do with it now.