NGC 3603 was difficult to process, so many stars interfering with the nebulosity!!
It was hard to decide where to stop with the minimum pass filter to reduce the stars. I think the colour of the nebulosity is about right, looked at many images and just took an average.
NGC 3603 (bottom cloud) is an open cluster of stars situated in the Carina spiral arm of the Milky Way around 20,000 light-years away from our solar system. and is surrounded by the most massive visible cloud of glowing gas and plasma known as a H II region in the Milky Way.
NGC 3576 (top cloud) is a minor nebula in the Sagittarius arm of the galaxy a few thousand light-years away from the Eta Carinae nebula. It is much closer and smaller than the distant 3603.
Equipement.
Telescope 8" f/4 astrograph.
HEQ Pro 5 mount - orion mini guider.
Camera canon 1100D at ISO 800
15 x 5 minute subs - 9 darks - 9 flats - 9 bias.
mmm laptop screens are noted not to be the best. There are better screens than others but i have a Spyder monitor calibrator. It sets a colour profile and loads it though the graphics card. That way you can be assured that the colour reproduction is in the ball park.
The other way in photoshop is to use the eyedropper tool and the RGB values,
just hover it over the stars and it'll show you the rgb component.
I used to use that extensively with the printing industry when my monitor wasn't calibrated so we check either RGB or cmyk values
I had a quick play with your image in gimp and came up with the attached, hope you don't mind. I still couldn't change the purple tinge though.
on 3 of my LCD's, there's a purplish tinge to the stars.
IMO, Just play around a bit more with the processing and change the hues on midtones or shadows and less on highlights, that would preserve star colours to a certain extent.
Can see a slight difference, can't see purple in the stars.
Might go and buy a better screen!
P.S. Two of my brothers are in the printing Industry.
Cheers,
Justin.
yep, they'll know what I mean. I spent hours colour correcting a scan on my monitor, but was shocked when it came back from the printers.
see if you can get an icm profile for your display.
Thats the new model of what i use and a 20" Phillips wide screen thats 4 years old and it almost matches the print perfectly to the colours coming out of the printer!
But yes using the RGB eye dropper can do it too if you know what your looking for.
check your histograms in PS youll see what im talking about 
