A mere 4.2hrs at 0.5"/px, only 25% of which was L, but this galaxy doesn't need much... that said, could do with a longer integration.
Almost didn't photograph this because I thought it might be a bit too big for my tiny sensor, but it didn't turn out feeling as claustrophobic as I thought.
Thanks very much guys, appreciate the feedback :-)
I decided to tweak it a bit, probably some good and some bad in that, but hopefully a net win. Might get some more data on it next weekend if the forecast holds up.
Now that some time has passed I'm not as happy with this as I was initially... definitely needs a lot more data and a reprocess. I'm on leave next week and the forecast is looking promising, so fingers crossed I get some decent seeing so I can do better on this one.
Had some good skies here lately; good seeing, dark. Had one mishap where for some reason I ended up with 4hrs of really sharp data containing only the tip of the galaxy, but last night everything came together.
I've now got this up to 9.8hrs and have reprocessed it. Still not sure on the colour, but I think it's better. Might revisit the processing again, but I think I'm done with acquisition and plan to move on to other targets.
Looking overall superb. A fine minor points. I would concentrate at this point on trying to sharpen up the data. It looks like it could be sharpened more with the right techniques.
The star colours are slightly oversaturated. I personally like the colours you have in the galaxy but the stars look a bit candy.
I would only concentrate on getting extra luminance and working with that layer to sharpen it up as much as you can before artifacts start to appear.
I remember ages ago when I was first starting out one prominent member here (who stopped posting years ago for some reason) did a super sharp Eta Carina image on a 12.5 inch RCOS. He showed how much unsharp mask he could apply with increasingly longer exposure times. By the time he got to 16 hours he could get it really sharp. A valuable lesson.
Fabulous image Lee, I tend to agree with Greg about the colours but otherwise it looks great, well done, enjoyed the view .
I was up in far North QLD last week, 3hrs drive west of Cairns, under dry Bortle 1 skies with a 24" F4.2 Dob (The Milky Way cast an obvious shadow and the Gegenshein and the rarely seen faint zodical bridge were easy to see all night) and this mighty galaxy looked absolutely incredible and almost blindingly bright, the detail in the disc was like a 5min Luminance sub through say, an 8" scope? ..I looked hard but couldn't convince myself of being able to see the faint perpendicular dust streams that rise from the middle 50% of the disc, and visible in your shot, but a number of star knots and dust lanes were quite noticable as was the barred spiral like shape. The central atar in the Ring Nebula was visible without averted vision and I comfortably tracked down several 16.5mag galaxies in Aquarius using the Argo Navis and could have gone fainter but didn't have any fainter references ...needless to say, t'was an incredible 3 clear nights of viewing!!
Quote:
Originally Posted by gregbradley
I remember ages ago when I was first starting out one prominent member here (who stopped posting years ago for some reason) did a super sharp Eta Carina image on a 12.5 inch RCOS. He showed how much unsharp mask he could apply with increasingly longer exposure times. By the time he got to 16 hours he could get it really sharp. A valuable lesson.
I believe that would have been one Brad Moore and his remarkable keyhole image was taken with his new 12.5 RCOS, it featured on APOD back in early 2006 I think?...and to this day is still a benchmark amateur image of the Keyhole really he also did a deep and detailed wider field Tarantula too, over 30hrs if I recall...not a common practice back then he had just got a new PME and I think was waiting for his RCOS so whacked a small Tak or something on it in the meantime
Looking overall superb. A fine minor points. I would concentrate at this point on trying to sharpen up the data. It looks like it could be sharpened more with the right techniques.
The star colours are slightly oversaturated. I personally like the colours you have in the galaxy but the stars look a bit candy.
I would only concentrate on getting extra luminance and working with that layer to sharpen it up as much as you can before artifacts start to appear.
I remember ages ago when I was first starting out one prominent member here (who stopped posting years ago for some reason) did a super sharp Eta Carina image on a 12.5 inch RCOS. He showed how much unsharp mask he could apply with increasingly longer exposure times. By the time he got to 16 hours he could get it really sharp. A valuable lesson.
Greg.
Thanks Greg, solid advice there. I've had another look at the final image after reading your comment and noticed that it looks a bit softer than the luminance data would suggest. The luminance data was 1.9" FWHM integrated, which is pretty good, but I'm imaging at 0.5"/px so I'm a bit oversampled still, which will make it look a bit softer... that said, 1.9" integrated is still pretty damned sharp.
I think I know the cause... I've deconvolved the luminance data and then combined it with some pretty noisy, lower quality RGB data and then turned the saturation to 11. I think that's resulted in the image looking softer than it should (because the chrominance data was softer). Based on that, I'm changing my plans for tonight and intend to invest more time in this target, specifically aiming to beef up the chrominance data. I might also try deconvolving the chrominance data. Will be interesting to see what difference it makes.
Quote:
Originally Posted by Atmos
It's come together really well Lee, very well done
Thanks Colin :-) Looks like I'm not done with this one yet afterall.