Hi
better late than never I guess. love how the background galaxies show through so brightly in the dim parts of the halo. http://astrob.in/283118/0/
the colour image has not been stretched enough to show the deepest detail, but, with 4x4 software binning and inverting, the loop that Paul mentioned can be seen to the lower right (also visible in the AAT image and Mike's 2012 deep image also shows it)http://astrob.in/283119/0/
With the binning, this image gets down to about 26 vmag/arcsec2. Clearly need to do some work on my flat fielding at this depth and the stars look as though I need to clean the mirrors as well - or maybe it was just atmospheric haze on one of the nights that caused the close scatter
That's a very good NGC 1316 Ray - smooth and detailed. You might consider using high pass filtering on the centre to bring out even more detail. Seemed to work for my image of it.
That's a very good NGC 1316 Ray - smooth and detailed. You might consider using high pass filtering on the centre to bring out even more detail. Seemed to work for my image of it.
Cheers
Steve
thanks Steve - will give it a go when I get enough enthusiasm to look at it again. Our images look quite similar otherwise
Quote:
Originally Posted by IanP
Great shot Ray, so many details, galaxies, busy frame, luv it
thank you Ian!
Quote:
Originally Posted by SimmoW
Yes lovely Ray!
Have you tried combining longer subs? Im finding 10-15 mins at 75 gain very effective for this purpose.
thanks Simon. at gain 100, the core of this thing is at about 55,000 ADU, so i can't go any longer without saturating at f4.
Quote:
Originally Posted by alpal
Excellent image Ray,
I am surprised that you used so many short 60s L subframes - 433.
cheers
Allan
thanks Allan - deliberate choice to maximise resolution and minimise guide errors - and keep from saturating on the core (see above) - I use 2 minute subs on most things these days, but the core on this one is very bright.
Apart from Mike Sidonio's amazing shot, not overly familiar with this one. Looks like you've done very well indeed, especially getting some of the fainter stuff. The distant face-on spiral toward top right came out well.
Regarding hundreds of 60 second subs, might be worth having a go at longer ones just for the convenience. You could also have a go at the only moderately horrible maths for working out how long an exposure would be sky limited rather than exposure limited.
thanks M&T - Stevec35 recently posted a really nice image.
fwiw, the maths is in this spreadsheet: http://www.iceinspace.com.au/forum/s...d.php?t=151000
my f4 system is within 5% of fully sky limited at 60 seconds since the read noise of the camera is below 2e. I have been using 2 minute subs for convenience, but lose a bit of dynamic range in doing so.
Another excellent galaxy shot Ray, this is a favourite of mine. In a deep image like this that showcases all the folds and shells so well, makes it appear so ethereal and magnificent at the same time. As usual some excellent detail from one of the masters. As Steve says there is some detail inside that bright core that I am sure you could reveal if you so desired but equally, by keeping the core glowing as you have, probably looks more real (I hear it is about respecting something...? )
Regarding the faint outer loop, yes, there aren't many images out there that show it well, or even at all.
thanks M&T - Stevec35 recently posted a really nice image.
fwiw, the maths is in this spreadsheet: http://www.iceinspace.com.au/forum/s...d.php?t=151000
my f4 system is within 5% of fully sky limited at 60 seconds since the read noise of the camera is below 2e. I have been using 2 minute subs for convenience, but lose a bit of dynamic range in doing so.
Wow! The world is really changing, and Trish and I are still riding on the wings of a pterodactyl. I suppose that since we can do 1 hour narrowband subs, the fact that we need to is less onerous.
You sure have plenty of subs for doing statistical outlier rejection and/or drizzling. The latter is out of the question for us with perhaps 6 subs a night. (Tonight we're having a bash at a patch of the Vela SNR, and will get 7 frames if all goes well and the pterodactyl doesn't crash).
Very nice Ray and well done for showing that outer loop
From memory Steves and Mikes had a bit more contrast at the core of the main galaxy which I think is what Steve was getting at; making the black pop
I've never had a go at this object either, but it sure looks tough Excellent, subtle details in the shells, Ray, and a very classy image overall.
Hi Rick - thanks very much. It is an interesting target, with a very wide dynamic range. what you end up with depends as much on your decisions as on the data.
Quote:
Originally Posted by strongmanmike
Another excellent galaxy shot Ray, this is a favourite of mine. In a deep image like this that showcases all the folds and shells so well, makes it appear so ethereal and magnificent at the same time. As usual some excellent detail from one of the masters. As Steve says there is some detail inside that bright core that I am sure you could reveal if you so desired but equally, by keeping the core glowing as you have, probably looks more real (I hear it is about respecting something...? )
Regarding the faint outer loop, yes, there aren't many images out there that show it well, or even at all.
MIke
thanks very much Mike - appreciate the comments. I tried to keep it looking as real as possible and the core detail is almost totally compressed at this stretch. However, agree that it is there and I will try to bring it out a little more in future processing. processing images to show fairly deep detail is a bit like squeezing a balloon - get it to do what you want it in one place and it pops out somewhere else.
Quote:
Originally Posted by Placidus
Wow! The world is really changing, and Trish and I are still riding on the wings of a pterodactyl. I suppose that since we can do 1 hour narrowband subs, the fact that we need to is less onerous.
You sure have plenty of subs for doing statistical outlier rejection and/or drizzling. The latter is out of the question for us with perhaps 6 subs a night. (Tonight we're having a bash at a patch of the Vela SNR, and will get 7 frames if all goes well and the pterodactyl doesn't crash).
I envy you. when I do calibration/stack on 600 odd 16mp subs, it takes a good part of a day on an i7. However, it is nice to be able to just shrug the shoulders if some intermittent cloud came through and ruined 20 subs
Quote:
Originally Posted by Atmos
Very nice Ray and well done for showing that outer loop
From memory Steves and Mikes had a bit more contrast at the core of the main galaxy which I think is what Steve was getting at; making the black pop
By no means makes it any less of a fantastic shot
thanks Colin. I tried to get it looking vaguely like a low res version of the ESO image https://cdn.eso.org/images/publicationjpg/eso1411a.jpg and didn't put in much effort on the core. will have to re-look at the original data, since a simple high pass filter on the stretched image (as Steve suggested) does too much damage by bringing out the noise on this image. That will have to wait, been looking at this image long enough for now .
thanks very much Mike - appreciate the comments. I tried to keep it looking as real as possible and the core detail is almost totally compressed at this stretch. However, agree that it is there and I will try to bring it out a little more in future processing. processing images to show fairly deep detail is a bit like squeezing a balloon - get it to do what you want it in one place and it pops out somewhere else.
Agreed and what you settled on looks perfectly fine to me mate, no need to process out the inner details...unless you want too ...be cool to see in a separate version though
) 
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