NB is way out of my comfort zone, but there has to be something to do when the moon is up. tried to keep the colour as close as possible to the broadband versions on the web.
there is no real point in high resolution with this object, so it is software binned 2x2 to improve the SNR. It really is a spectacular region though, with a huge cavity opened up by the bright new stars and very ragged tendrils all over the place.
250f4 Newtonian with ASI1600 at gain 100 and 200. Ha=54x600s O3=39x600s. Thanks for looking. regards Ray
Very nice, Ray Maybe just a little too biased towards Ha/red? Not sure you should take too much notice of that comment after my last couple of images, but I'd treat this one a little differently The detail is fantastic, BTW
"Thor's Other Helmet" as Fred calls it looks sharp and deep. The globular at the bottom of the image adds lots of interest (it's out of field for us).
thanks very much - appreciated
Quote:
Originally Posted by DJScotty
That's very nice Ray. Good work!
thanks Scott
Quote:
Originally Posted by Atmos
Really nice Ray. Did you find the 2x2 binning help a lot?
thanks Colin. binning did no damage, but improved the SNR by a noticeable amount.
Quote:
Originally Posted by RickS
Very nice, Ray Maybe just a little too biased towards Ha/red? Not sure you should take too much notice of that comment after my last couple of images, but I'd treat this one a little differently The detail is fantastic, BTW
Thanks Rick. I am incompetent at this, so tried to keep colour as close to a variety of broadband images as I could - maybe with limited success. Will have another look at reducing the red a bit.
Quote:
Originally Posted by gregbradley
Beautifully done. Look how tightly resolved those small bright central stars are.
Wonderful.
Greg.
thanks Greg. taking the sampling down to ~1.6 arcsec sure makes the stars look nice and small doesn't it?
Quote:
Originally Posted by glend
Love it Ray! Great detail in the central core cluster area. How did you prevent diffraction spikes?
thanks Glen. the spikes are there, but not very pronounced in NB, especially with binning.
Love it Ray, very natural looking other than the red cast/background.
Not hearing much on the forums re. binning this camera, so I'd love to see a comparo of bin2 vs bin1. Could you pm me a link to any files? or better yet, post here for others to see too?
Hi Ray, whilst I don't understand your comment, I do appreciate that you have done a great job on this difficult target.
I say difficult having imaged it twice for a zillion hours in NB but I have yet to find a truly pleasing colour palatte, as indeed you have done here.
The image is well composed, nicely balanced and maybe just a tad red, and it's very good result.
thanks Andy. the comment on resolution could have been better expressed, but the point I was trying to make is possibly illustrated in the unbinned/binned comparo http://astrob.in/full/289059/0/ which shows (I think), that there is little point in displaying a big billowy neb like this at full resolution for web viewing - it looks better and is easier to take in at lower scale - and, apart from some very faint stars, there doesn't seem to be any loss of significant information.
Quote:
Originally Posted by SimmoW
Love it Ray, very natural looking other than the red cast/background.
Not hearing much on the forums re. binning this camera, so I'd love to see a comparo of bin2 vs bin1. Could you pm me a link to any files? or better yet, post here for others to see too?
thanks Simon. I chose a reddish cast because the DSS1 data show some extensive red nebulosity surrounding the main region. However, I take the point and will reprocess some time soon.
the binning was not done on the camera, but in software (Nebulosity), after it was all processed. My understanding is that the camera does not do a very good when binned (loses a couple of bits of dynamic range), so I have never used it that way. The image at http://astrob.in/full/289059/0/ shows some non-binned and binned data - I think that the extra SNR and perception of sharpness justifies binning.
It is a lot better to software bin than hardware bin with this camera. I would argue that it is better to process unbinned (especially for decon as larger stars respond better than smaller) and then reduce resolution later on.
I think what Ray is getting at with the binning on this nebula is that there is no high contrast regions that suffer. Taking Eta Carina as an example, there are a LOT of high contrast regions in and around the Keyhole Nebula that benefit from as much resolution as possible.
NGC 1760 is a lot more whispy with some detail in the nebulosity but virtually no contrast.
I agree it is a great object. I have imaged it twice in recent year and think it has a lot to offer for imagers. Probably better in full NB I think. Glad to see you tip toeing into the NB waters Ray.
You're definitely on a roll Ray. That looks great. The colour is so natural that it's hard to pick it as a NB image. Extremely nice composition too with that little cluster at the bottom
It is a lot better to software bin than hardware bin with this camera. I would argue that it is better to process unbinned (especially for decon as larger stars respond better than smaller) and then reduce resolution later on.
I think what Ray is getting at with the binning on this nebula is that there is no high contrast regions that suffer. Taking Eta Carina as an example, there are a LOT of high contrast regions in and around the Keyhole Nebula that benefit from as much resolution as possible.
NGC 1760 is a lot more whispy with some detail in the nebulosity but virtually no contrast.
yep, that was what I was getting at - the nebula does not have much fine detail, so full res is not needed.
Quote:
Originally Posted by Paul Haese
I agree it is a great object. I have imaged it twice in recent year and think it has a lot to offer for imagers. Probably better in full NB I think. Glad to see you tip toeing into the NB waters Ray.
Thanks Paul. Am trying to keep on the edge of the NB waters - they look pretty deep
Quote:
Originally Posted by Regulus
This is a very effective image Ray. Well done.
Trevor
thanks very much Trevor
Quote:
Originally Posted by Stevec35
You're definitely on a roll Ray. That looks great. The colour is so natural that it's hard to pick it as a NB image. Extremely nice composition too with that little cluster at the bottom
Cheers
Steve
Thanks Steve. Appreciate your comment, because I put a lot of time into balancing the colour so that it looked as close as possible to a broadband image that I found.
The detail is fantastic, BTW 
