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View Full Version here: : Horsehead and flame


etill
26-03-2021, 08:21 PM
I wasn't really planning on using these subs, I've been mainly focusing on getting my equipment dialed in properly. These are from about two weeks ago when I was trying to work out the tilt using CCD inspector. After hours of adjusting things I just picked a target and setup a seqeuence to catch some data for testing calibration and other things and then went to bed...

When I stacked these to check how well I was able to calibrate with flats (just switched to flats+flat darks and don't bother with bias anymore) I was pretty suprised.

18 x 180s @ -10c QHY10
Baader MPCC
Vixen 200mm/F4
Celestron CGEM (just converted to belts)

Processed in pixinsight
linear fit, normalized DBE
photometric color calibration
median transform for NR
masked stretch
median transform with bias adjustment to sharpen

Its still really noisy but Alnitak was surprisingly gentle to the rest of the frame and for such a short integration I'm pretty happy.

Unfortuantely not able to add more data to this one, I've swapped from the baader mpcc to a paracor and re-introduced all of the tilt and curvature I was working on eliminating. Looking forward to another few weeks of tweaking the setup to get that sorted out.

PKay
27-03-2021, 06:47 AM
Hi Elliot

You should be happy and releived all those tedious adjustments have paid off.

Part of the game unfortunately.

Your result is very good.

My subjective thoughts:

I would move everything to the right a bit so that the horse and flame are centered together.

There is a trick you can do (easy to do in Photshop) is 'area selection enhancement' (my term).

ie: Select an area (say the flame) and adjust the saturation and colour balance.

Some might say this will cross the border from AstroPhoto to AstroArt but I don't think so.


All good fun and well done :thumbsup:

etill
27-03-2021, 08:04 AM
Thanks Peter, I definately see what you mean. There's also a little pocket just below the horsehead and to the left that pops right out with some extra processing with multiscale HDR but I can't quite keep it under control across the rest of the image and it introduces too much noise and other issues so I just undid that and left it as is.

I think it comes down to the quality of the masks I'm making but I wonder if the local histogram correction tool with very carful masking could work on the flame. Alnitak really makes the masking difficult in that area.

Another option I thought of might be earlier in the process when I have everything split up into rgb components for the linear fit. I don't do anything with the lum data there but I have read a lot of other peoples rgb workflow where there's a lot more processing of it before recombination.

AtlasPSD
01-04-2021, 11:10 AM
Very nice nebulosity and details! Feel like you could go a little stronger on the contrast for aesthetics sake, but hats off regardless for where the image is currently at!

multiweb
01-04-2021, 12:51 PM
Beautiful shot. Well done. :thumbsup: