This is my last one from the Ha run I had at home. NGC6188.
Just a little over 1h in 2min subs. Same rig. GSO8" F/4, QHY9 and Baader 7nm Ha. Moon was bright but Ara was far enough from it so contrast is better than the prawn. Although Wednesday night was bloody wet somehow, backwash from the cloudy East. That was a pita.
Full frame 1:1 here [3296x2460 - 3.6MB]
HD version here [1920x1433 - 1.4MB]
Posted version is a blown up crop of the region of interest.
That's it from me until the next batch of clear skies which is not happening in Sydney this week-end, that's for sure.
That's an impressive shot Marc. That really is extremely sharp and detailed.
Greg.
Thanks Greg. I was happy with the level of details in the center, yeah. Would love to do this one in Oiii and Sii as well if the weather cooperates but it looks like a wash out until Thursday next week. In Sydney anyway.
That's wonderful, Marc. By concentrating on H-alpha, you've shown that the cloud occupying the central third of the image is much brighter than the one to its left, something that is often completely concealed in tricolour narrowband images. Incredibly sharp - lots of stars resolved in the important central cluster. You can even see several very faint circular shock fronts in that central region that are normally only really obvious in OIII. Nice.
That's wonderful, Marc. By concentrating on H-alpha, you've shown that the cloud occupying the central third of the image is much brighter than the one to its left, something that is often completely concealed in tricolour narrowband images. Incredibly sharp - lots of stars resolved in the important central cluster. You can even see several very faint circular shock fronts in that central region that are normally only really obvious in OIII. Nice.
Thanks Mike. The first picture I've ever seen of it was an RGB shot you did with a C11 about 7 years ago, called "the Ara shoreline". That was a brilliant shot and it's still burnt onto my retina. Been shooting it since then, every opportunity I get.
Pumping out some sharp images Marc but with a forum saturated with mainstream targets like NGC6188, can you get away with Ha only? Its a great presentation of the detailed ridge of emission neb. Stars don't come much rounder than that. Nice! More, but with a hint of colour please.
Pumping out some sharp images Marc but with a forum saturated with mainstream targets like NGC6188, can you get away with Ha only? Its a great presentation of the detailed ridge of emission neb. Stars don't come much rounder than that. Nice! More, but with a hint of colour please.
Thanks mate. I might do a sepia version for you, like back in the day
very nice Marc,
i notice you are getting away with quite short Ha subs ... most people seem to go about 5x longer?
Cheers
Russ
Thanks Russel. The QHY9 has quite a low read noise so I can get away with it. These 3 clear nights we had, I was collimating the scope and also collecting a lot of data for the temperature compensation of the focuser. I'm doing this because I need to work it out for the FSQ next. The newt CFZ is a lot easier to play with.
So the shorter subs allowed me to get a lot more points as I was refocusing very often, monitoring the FWHM. The third night I had enough points in the temperature logs to fit a line in Excel and I only did minor adjustments to the automated process. That's why all that stuff was shot in 2min subs.
I was happy with the level of details in the center, yeah. Would love to do this one in Oiii and Sii as well if the weather cooperates but it looks like a wash out until Thursday next week. In Sydney anyway. 
