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Ryderscope
24-08-2019, 07:54 PM
Continuing the progress with my NGC6334 project, I now present herewith the LRGB version of this well known object. This image has certainly proved that every processing journey is going to throw up new challenges. The dynamic range and sheer concentration of data in the red end of the spectrum made it quite interesting to process whilst keeping a lid on saturation and brightness. I suppose that there is a strong subjective element in our approach to colour and saturation and this is no doubt reflected in where this image has landed. I was originally going to do a RGBHa image but I didn't like the result so settled for LRGB which actually presents better IMHO. The Ha will have its chance to shine next when I get on to the SHO processing.

Approximately 12 hours of data collected during June/July with my TSA 120 @ F5.6 and QSI 683 WS-8 CCD.

Link to image on Astrobin here. (https://astrob.in/422315/0/)
Click on image in Astrobin for larger version.

Comments and critique welcome.

Clear skies,
Rodney.

Atmos
24-08-2019, 08:28 PM
Really nice detail and contrast in the Ha regions Rodney. One of the best parts about RGB as opposed to HaRGB is the colour balance and this looks spot on.
Love the stars from the TSA, such good correction :thumbsup:

peter_4059
24-08-2019, 08:34 PM
Super image Rodney. Nicely captured and processed.

dave_galera
24-08-2019, 09:42 PM
Nice image and processing, this is on my list to image in the near future.

Sunfish
24-08-2019, 10:01 PM
Thanks. Great image. So that is what the LRBG Cat is supposed to look like.

Geoff45
25-08-2019, 08:40 AM
Shaping up nicely Rodney. I completely agree with leaving out the Ha. It often doesn’t work when there is already a lot of red showing up. I like the detail in the top right paw. Interesting purple colour in the bottom paw.

Ryderscope
25-08-2019, 09:26 AM
Thanks Colin and Peter. The observation on the star field from the TSA 120 is appreciated given the number of hours that I have spent on chilly nights mucking around until the early hours of the morning with field flatteners, focal reducers, new focusers, auto focus stepper motors, playing trial and error with spacers and backfocus distance, tilt adjustments etc. etc. I finally have a configuration that seems to work so I am sticking with that for now.

Ryderscope
25-08-2019, 09:37 AM
Thanks Dave. I popped in and had a look at your gallery and you have an excellent portfolio of images. You definitely should add this one to your list.



Thanks Ray. There is certainly a wide variation of images of this area and I doubt that any two are alike. Makes the hobby more interesting I think.

Paul Haese
25-08-2019, 09:43 AM
A nicely balanced rendering of a target that is almost purely red. I like the luminance which gives a misty look here and there which often gets missed if you just use Ha. This is why I pretty much always collect luminance these days no matter if I intend to just use narrow band data or not. It just gives that little bit extra to the overall finish.

I agree that colour perception is entirely subjective. Everyone see colour at different levels of saturation (based on your own colour perception) and of course every monitor despite being calibrated will show slight differences in saturation and brightness. It's often a tricky process and each object has the need to be processed differently from others.

Ryderscope
25-08-2019, 09:54 AM
Thanks Geoff. I did notice the smatterings of a hint of magenta in a couple of locations. Almost like a dusty cloud of magenta drifting across the top of the image.



Thanks Paul. It certainly took a bit of trial and error on this one before settling with a combination that worked well.

multiweb
25-08-2019, 10:39 AM
Superb Rodney. :thumbsup::thumbsup::thumbsup:

Ryderscope
26-08-2019, 09:47 AM
Thanks for the feedback Marc.