Petergoodhew

A superb image Brendan - you should have "come in" long ago! I really like the subtle natural-looking colours. Peter

Quite possibly. Mine were bought then too.

I decided to go deep on this one - very deep - with 75 hours of data. Captured on my dual rig in Spain.

I had halos with Baader OIII filters too. I then discovered that they had made a faulty batch of OIII filters and this was the reason for the halos. Eventually Baader agreed to replace my filter free of charge on condition that I returned the faulty filter. My new Baader OIII filter has no halos.

Excellent detail David. Nicely done. Peter

Thanks Alan. I do tend to go for the more obscure targets! This one isn't that common in part because it's fairly low on the horizon at 12 degrees declination. Even in southern Spain it was only just peeping over the observatory walls. Peter

NGC 7479 (also known as Caldwell 44) is a barred spiral galaxy about 105 million light-years away in the constellation Pegasus. This is a total of 21 hours of integration. Captured on my dual rig in Spain. Scopes: APM TMB LZOS 152 Cameras: QSI6120wsg8 Mount: 10Micron GM2000 HPS

Thanks Alan. It’s rarely imaged because the core is very small and very bright. I’ve searched extensively online and haven’t found any images of these outer halos. Peter

Before starting an imaging run I now do some test images with different filters, exposures, and binning to see which combinations work best. When I examined the OIII 1800s bin 2x2 test image I was surprised to see an asymmetric outer shell with intricate structures, and so factored this into my image capture plan. This is the result. There is also a very faint diffuse OIII shell that is even further out from the core. I found processing this to be a real challenge, with 7 filters, and exposures varying from 30 sec bin 1x1 to 1800s bin 2x2. Integrating images with such extreme dynamic range was also a challenge. I was concerned by some lighter parts of the sky background, but after checking with other images available online it became clear that this was integrated flux nebula. This is a total of 57 hours of integration. Captured on my dual rig in Spain. Scopes: APM TMB LZOS 152 Cameras: QSI6120wsg8 Mount: 10Micron GM2000 HPS

That's got to be the best 7331+quintet I've ever come across Olly. It's worth foregoing the IFN for this! Interesting how things aren't what they seem. I had always assumed the quintet were all together. You got some really good colours too - the three hours per channel were well worth it. Smashing job. Bravo.

A remarkable image, well done. I've been to Olly's place several times. The sky is exceptionally dark there.

It's tricky. The bubble is only visible in narrowband - more so in OIII than Ha. I did 30-minute subs binned 3x3 to extract as much signal as I could. Clear dark skies help a lot too!

Thanks Dave

Thanks Steve. I've been wanting to have a go at this one for a long time. The filters were all Astrodons. Ha was 5nm, OIII was 3 nm.

A planetary nebula in the constellation of Cygnus - close to the Crescent Nebula. Only relatively recently discovered (2007) because of its extreme faintness hidden in bright hydrogen clouds. Also known as PN G75.5+1.7 43 hours total integration, captured from Extramadura, Spain. Scopes: APM TMB 152 F8 LZOS Mount: 10Micron GM2000 HPS Cameras: QSI 6120wsg8 APM TMB 152 F8 LZOS, 10 Micron GM2000HPS, QSI6120ws8

Carole, I find it's much, much more faint in broadband than narrowband.

I don't this there's a right or wrong to this. I've some images where selected the best subs made no difference at all - and others where it does. I think it will be down to the data. If there's very little difference between the quality of the subs, and especially if the target is faint, adding more will of course improve signal strength and thus help with deconvolution. However if a few subs are of exceptional quality, only using them could turn out to be the best strategy.

Hi Alan, yes I've experiemented with different selections of subs. The sugnal is very strong in these and so signal to noise isn't a problem. 15 subs represents 7 1/2 hours of data. Here I was able to do 200 iterations of deconvolution. I find that larger numbers of subs does reduce the clarity, and so settled on 15. Peter

A rarely-imaged extremely faint planetary nebula in the constellation of Serpens Cauda. It's also known as RCW 181 and PN G038.7+01.9. Captured on my dual rig in Spain. RGB 20x600 each Lum 22x600 Ha 21x1800 bin 2x2

Thanks Brian - the secret is lots of data, and then using just the best for pulling out the detail. Here I had 128 30-minute Ha subs but used only 15 for the fine detail. Deconvolution, high-pass filtering, and Annie's Actions helped too.

A more conventional target for a change - and one of my favourites. This time revisited with more data. 82.5 hours total integration HaOIIILRGB Image captured on my dual rig at EyE, Extramadura, Spain APM TMB 152 F8 LZOS, 10 Micron GM2000HPS, QSI6120ws8

Sharpless 1-89, a very small (1.1') and very faint (24 mag/sq") planetary nebula in the constellation of Cygnus. Also known as the Moth Nebula, PK 089-0.1 and PN G089.8-00.6). 42 hours 10 minutes total integration. Ha/OIII 60x1800s bin 1. Lum 40x600s bin 1. RGB 24x300s bin 2.

Splendid clarity, detail and colour. A superb image. Well done!

A very faint planetary nebula in the constellation of Virgo. It is at declination -20 and thus very low, even in Spain, just hugging my visible horizon. It is only 800 light years away with a span of 1.5 light years. The central star is estimated to have a temperature of over 73,00K compared with our sun at 6,000K. 29 hours 10 mins total integration (19x1800s OIII bin 3x3, 16x1800s Ha bin 3x3, 52x600s Luminance bin 1x1, 12x300s Red bin 1x1, 12x300s Green bin 1x1, 12 x300s Blue bin 1x1) Image captured on my dual rig at EyE, Extramadura, Spain APM TMB 152 F8 LZOS, 10 Micron GM2000HPS, QSI6120ws8

Thanks Olly - let me see what I can do for you!