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View Full Version here: : NGC 3603, so many stars!


tilbrook@rbe.ne
29-03-2012, 04:40 PM
Hi,

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.

Median stack in DSS, processed in Photoshop.

Cheers,

Justin.

bmitchell82
29-03-2012, 04:43 PM
Looks alright bar you have cooked the red like no tomorrow! :) check your histograms in PS youll see what im talking about :D

tilbrook@rbe.ne
29-03-2012, 05:04 PM
Thanks Brendan,

A question, what monitor is best when doing processing?
I'm using my lap top, and the screen is not the best.

Cheers,

Justin.

bmitchell82
29-03-2012, 05:10 PM
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.

alistairsam
29-03-2012, 06:01 PM
Hi Justin,

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.

tilbrook@rbe.ne
29-03-2012, 06:10 PM
Thanks Alistair,

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.

alistairsam
29-03-2012, 06:12 PM
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.

bmitchell82
29-03-2012, 06:33 PM
http://spyder.datacolor.com/product-mc-s4pro.php

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.

tilbrook@rbe.ne
29-03-2012, 06:47 PM
Thanks for that link Brendan.

I'm going to try processing through my flat screen LCD TV.

It gives better colour than my laptop, worth a go anyway.

Cheers,

Justin.

Ross G
29-03-2012, 08:33 PM
Hi Justin,

A very good photo of a nice looking object.

Ross.

LucasB
29-03-2012, 10:44 PM
Nice shot! You are producing some very nice photos.:thumbsup:
Lucas

tilbrook@rbe.ne
29-03-2012, 11:26 PM
Thanks Ross and Lucas,

We are lucky down under, so many amazing objects to choose from.

Cheers,

Justin.