This is 6 hours 27 minutes of data taken over two very dark nights, best I've had in ages and ages and at New Moon.
Telescope aperture and focal ratio: TS1506UNC f4, TS Komakorr
Camera and filters used: ZWO ASI294MC Pro, Baader Neodymnium 1.25" filter
Processing applied: DSS 4.x, Startools, Gimp
Forgot all this stuff is recorded by DSS, very useful! I used Bilinear alignment, seems to produce better results every time, and used "Align RGB Channels in Final Image". They are master calibration frames.
Iris Nebula DSS List
Stacking mode: Standard
Alignment method: Bilinear
Stacking step 1 ->93 frames (ISO: -) - total exposure: 6 hr 27 mn 30 s
RGB Channels Background Calibration: No
Per Channel Background Calibration: No
Method: Median Kappa-Sigma (Kappa = 1.50, Iterations = 1)
-> No Offset -> Dark: 1 frames (ISO : -) exposure: 4 mn 10 s
-> Dark Flat: 1 frames (ISO : -) exposure: 5 s
-> Flat: 1 frames (ISO: -) exposure: 5 s
Click for larger version, cropped but not binned/resampled.
(http://gallery.orpington-astronomy.org.uk/albums/userpics/10050/normal_NGC7023_Iris_Nebula_6h27m_E250_G121_O8_DSS_ST_Gimp.jpg) (http://gallery.orpington-astronomy.org.uk/albums/userpics/10050/NGC7023_Iris_Nebula_6h27m_E250_G121_O8_DSS_ST_Gimp.jpg)
Very good Duncan
Jealous of your weather! Lots of cloud with some skimpy little clearings here.
Nebula looks really good, but the stars are brilliant too.
Noel
Lovely star colour and dust Duncan.
The dust would show up even better with a slight stretch. Always difficult to get the centre of the nebula right as it is somewhat brighter than the rest. Possibly needs some shorter subs for that bit.
On the whole a very pleasing and nicely processed image Duncan, your processing has stepped up a notch recently, so does this mean you have overcome any gremlins you had?
Carole
Nice looking image , always liked this target,
Roger
Very nice Duncan.
Thanks all.
Carole, if I'd processed in Pixinsight I would have used the special script for bringing out the dark patches and dust, which I suspect is how most people get that 3D dust effect. I may have a go on this image as the script input doesn't have to be linear.
A tricky target that Duncan nicely captured and processed.
You must have been up till the wee hours capturing that one ?
Robert
Lovely result Duncan! Well processed - I love the dust and the star colours. An object like this does need quite a few hours of data and you've done the right thing by spending a couple of nights doing the acquisition.
An all round great result.
Mark
Fantastic result Duncan 8) This is a tough object but your colours are spot on and the framing is great.
Roberto
Thanks all. I must admit I'm very happy how it turned out.
On a slightly different subject but related to your camera, have you seen this thread concerning a weird background effect in the red channel:
https://www.cloudynights.com/topic/661685-word-of-warning-asi294mc-pro-and-opt-triad-and-nb/
Mark
Very interesting Matk. I don't use anything but a Baader Neodynium filter however I get a doughnut shape on flats. Never used to so I think its reflections in the scope, I have repainted the OTA and every screw and nut and just need a dark clear night to collimate and test it out properly.