Image Processing - Modified Canon DSLR Cameras

I'm wondering if there is a standard amount by which the saturation of the red should be reduced to give a more "natural" appearance?

Mike.
Let me offer my 2 cents here.

Astrophotography to begin with is most 'Un Natural'
There is no getting away from this fact.
(Unless you have your camera settings set to record exactly what
the human eye would see looking at a particular scene)
then all the rules go out the window and out into space

Therefore because the human eye cant track at sidereal rate,
stop down the iris as we wish and increase our colour sensitivity,
essentially if it looks 'natural' to you then how can anyone else argue
with you?

We sometimes say an image looks 'overprocessed'
or 'too dark / bright' but essentially we are looking at an
image the human eye could never ever see and then processing
it using only our own inherent memory of the night sky to force it
to look like what we imagine it should look like
( if we had ccd chips for eyes.)

I think sometimes people approach the image processing side of astrophotograhy a little to
analytically.
(especially engineers )
True there are some basic 'rules' to follow but my own personal opinion is
that unless you are specifically trying to tease out things in an image
the the human eye cant see through an eyepiece then essentially
'no rules apply'.

As for how much to increase or decrease a colour, in this case red,
I'd say forget about formulas and rules,
just play around with the image until you are happy with it.
I'm slightly colour blind in the red/green, have a crap laptop monitor
to process on and somehow they come out looking ok to other people.
Maybe it's the crap laptop!
:lol:

In any case Mike,
please post up your reprocessed work so we can see the differences.

I gave Deep Sky Stacker a try this evening.
Cool little program with very nice features.
I love the way it can work directly with Canon RAW files.

Below is an attempt to process an image I showed earlier which I captured over on Mt. Parnon.
Any suggestions on how the image could be improved would be appreciated as I am not too familiar with the DSS program.
www.astroshot.com/Greece-2008/2008-07-05-Milky-Way-V2.jpg
The Hutech-modded 300d is much more sensitive in the red than the standard camera. While I want all the extra detail that the camera captures, I don't necessarily want to keep the extreme bright red colours. I'm wondering if there is a standard amount by which the saturation of the red should be reduced to give a more "natural" appearance?

*I've split these posts from the Mt. Parnon thread and pulled them over here. Unfortunately, I made a bags of it and the order of the posts has now changed. To make sense, it should read with mine first, and then Franks post.*

Therefore because the human eye cant track at sidereal rate,
stop down the iris as we wish and increase our colour sensitivity,
essentially if it looks 'natural' to you then how can anyone else argue
with you?

We did offer to strap you to the Astrotrac!

I think sometimes people approach the image processing side of astrophotograhy a little to
analytically.
(especially engineers )

Guilty as charged. Seriously though, it is something I am acutely aware that I sometimes focus too much on the technical side of it and miss some of the artistic elements in it.

In any case Mike,
please post up your reprocessed work so we can see the differences.

This is the original image from the camera:
www.astroshot.com/Greece-2008/2008-07-05-Milky-Way.jpg
Processed image:
www.astroshot.com/Greece-2008/2008-07-05-Milky-Way-V2.jpg
Second one looks a little too orange right now I think.

Second one looks a little too orange right now I think.

I'd have called it brownish but I guess it's my eyes.

Sometimes in music if you are 'mixing' a track and say you want
more bass,
you can decrease the treble and high to give the impression of more bass
without actually muddying up the track.
(Pheonix can probably better explain that than I can)

So sometimes I dont go near the colour I want to change,
I change the primary opposite and some of the other hues to in effect
change the perception of the colour.
I'm not exprienced in processing deep sky images but I'd reckon it
may be helpful in retaining the detail in nebula or HA regions.

Try increasing the opposite colour to the one you want to 'dim'
This colour wheel may help
www.owlnet.rice.edu/~psyc351/Images/ColorWheel2.jpg
If the image becomes too saturated you can pull it back in 'satuaration'
see if that helps.

Thanks for the tips Frank.

After playing with the image again, I think I have settled on this:

www.astroshot.com/Greece-2008/2008-07-05-Milky-Way-V3.jpg

Image shows M16 (The Eagle Nebula) and M17 (The Swan Nebula) to the right of the image with Sh2-54 emission nebula above M16. Gamma Scuti is located near the centre of the image. This images consists of 2x6 minute exposures combined in Deep Sky Stacker and later processed in Photoshop CS3. Image taken using Hutech-modified Canon 300d set to ISO400 and Canon 100-400mm L IS USM lens set at 100mm focal length. The sky was so incredibly dark, I could see my own shadow cast by the light of the Milky Way! What an experience!