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astropintr
20-06-2007, 06:20 AM
Hallo south guys!
Before 3 days I took picture of nebulae NGC 7000 in CYGNUS in the northern hemisphere. I took picture with my Skywatcher ED 80/600 and unmodified CANON EOS 350 D. I was very surprised with result!

Date: 17. 6. 2007 00:15 - 02:45 SELC
Skywatcher ED 80/600 + Canon EOS 350 D unmodified
exposure: 13 x 5 min, ISO: 1600
manualy guided with refractor 70/500
processed: Subraw, Adobe Photoshop 7.0 CE
weather: clear sky, temperature 12 C
:)

jase
20-06-2007, 09:20 AM
Nice camera and telescope combination. You've framed the North America Nebula well and a top effort for manually guiding.:thumbsup:

Two comments;
You're colour balance needs improvement. Boost Yellow and Magenta to bring the stars back to a white/blue appearance (this can be done for highlights only to keep the nebulosity tones). Also the image displays noise in the dim regions. Perhaps use a layer mask or the colour range tool in PS to selectively reduce noise in those areas.

FOOTPRINT
20-06-2007, 09:40 AM
Hi,
This is a very good result, nice sharp focus good contrast, and the colour is good also considering the Canon is unmodified, keep up the good work, look forward to seeing some more Pix. from north of the Equator, have you tried M51.

cheers....Jim

astropintr
20-06-2007, 04:12 PM
Colour balance is problem with unmodified Canon. If I applied correct color of nebulae, color of star will be not good. If you have unmodified Canon, you must use copromise.

Thank you very much for your comments!

Pavel ;)

RB
21-06-2007, 01:51 PM
Hello Pavel,

Very nice shot of NGC 7000, v.nice detail, sharpness and guiding.
I think the colour balance can be rectified though somewhat without disturbing the star colours too much.
Would you mind if I have a go adjusting the colours in your image and post it here?

Cheers
Andrew

astropintr
21-06-2007, 04:09 PM
Yes,
you can processed my photo! Thank you very much for your activities!
I am looking forward of your processing!

Thank you! Pavel:thumbsup:

RB
21-06-2007, 10:05 PM
Here's what I came up with using Photoshop CS2.
Spent some time adjusting the colour balances and the Hue/Saturation.

Thank you for letting me have a go, it's been raining here so haven't done any imaging in a long while.

astropintr
22-06-2007, 05:26 AM
Very nice! Great work! But only one comment! The stars are not good color, I see only white. But there are also stars, which are yellow colors. But very nice color of nebulae! ;)

RB
22-06-2007, 09:42 AM
Glad you liked the colours of the neb.
I really liked the detail in your image, the original size must look awesome.

I understand what you're saying about the star colours.
Working from a small jpg web version of your web image I was limited as to how far I could adjust the colours (I usually work in 16 bit .tiff).
Also colour tints in images look different on different types of monitors too, what looks like yellow tints in some of the stars on my CRT might look completely white on an LCD monitor or laptop or even another CRT.

The main thing I wanted to show was an example of what can be done in terms of colour correcting the image "without disturbing the star colours too much".

Thank you once again for the opportunity to have a go, I've enjoyed viewing your image and look forward to seeing more of your work.

:thumbsup:

jase
22-06-2007, 05:11 PM
Normally, I wouldn't do this as modifying an image in such a highly compressed state is a recipe for disaster. Really lacking dynamic range to play with, but I thought I'd provide an insight to one of the ways to remedy star fields/colours in PS.

Created a duplicate layer of original - now you have two layers to work with - one for stars, the other for nebulosity (you can go on a create many other layers depending on what you want to achieve, but the complexity level increases. I try to keep the layers no more than 6, but sometimes go to 8 if I'm working with Ha info. Mosaics are a different story.

Drop the red channel via curves on the duplicate (as can been seen on PS histogram) - red balance is higher than other channels. This brought out more blue balance. I perhaps over did this a little. Then with the PS colour range tool selected specific stars that I wanted to come through and modified the fuzziness to include some of the smaller fainter ones deep within the nebula.

Then on this modified layer, I created a reveal selection layer mask. This allowed the nebulosity to come through, from the original (background) layer, but also bring out the stars. Seasoned to taste. I’ve left the nebulosity untouched (other than boosting saturation) as manipulating this results is too much noise for my liking. The nebulosity is rather muted IMO. Needs more saturation. You "chase" the details by using other layer masks to provide greater control.

I pushed the blue a little too hard, but I think I got my point across - balancing star colors is important for aesthetics. Regardless of what you're using to capture the night sky, it is possible to push the limits in processing.

Dr Nick
23-06-2007, 05:03 PM
Wow! very nice! ;)

astropintr
25-07-2007, 05:10 AM
Hallo guys,
according your comments I used layers for better results color of nebulae.
I think, that color of nebulae is better and color of stars also...
:)

RB
25-07-2007, 09:04 AM
Great work Pavel !

:thumbsup:

Ric
25-07-2007, 10:24 AM
Great image Pavel, what a massive nebula it must be. This is one I have yet to see as it is quite low on my horizon at the best of times.

Cheers