Colour rendition

[LewisM]

Probably a hot topic (been good at picking those lately), but where do we draw the line on proper rendition of DSO, especially nebulosity.

M42 is a CLASSIC example - I have seen SO many varying colour pictorials on M42, it's hard to conclude what is actual/real colour! I have seen from nearly all blue, to hot pink to every imaginable variation.

I TRY to deliver my images in what I PERCEIVE is natural colour rendition - fairly mute at that - but is there a so called bench mark standard to compare to/strive to emulate? I thought Hubble may be a good start, but SO many are in false colour, and sometimes it is not annotated that the image is false colour.

I acknowledge there are definite colours for each gas emitted, but of course the intensity/hue depends on MANY factors.

Really would like some constructive discussion on this one

[multiweb (Marc)]

I was actually chatting with someone who saw it through a very large telescope (4m) and he said the sword is bright pink but the area around it is green. The outer shell is pink then deeper red and brown. So is the core of the tarantula. Green. But green is considered an evil colour by most astro imagers for some weird reason. There is also a green removal plugin for PS called HLVG.

[LewisM]

I know LOL

When I was rendering my latest M42 image, there was some green showing in the outer shield (above the "bubble" especially). I erroneously muted that a little, since NO images tend to show it! There is a tinge of it still there, but not a great deal. I was happy to extract a good deal of brown though.

[skysurfer]

Colors in M42 ?

Yes a 4m telescope will reveal it but an amateur scope of at most 40cm ???
Did anyone see colors in M42 (or another bright example: NGC3372) with an amateur scope ?

[Octane (Humayun)]

I've seen green/pink in M42 through a 25" Dobsonian.

H

[LewisM]

I am talking IMAGING

So, what the CAMERA should be displaying in the output

[Octane (Humayun)]

It's all subjective creativity.

Sorry for going off topic. It won't happen again.

H

[technofetishism (Nick)]

what exposure is the camera using, that will effect the colour shown. is it an astro or full spectrum modified camera?

[LewisM]

OK, I must have not been overly clear - in the final packed, vac'd and stacked image, thrown into PS or whatever PICTURE editor you use, what BENCHMARK to use to judge colours?

I understand personal choice, but surely there is some benchmark to which to match colours?

H, go off tangent all you like - it's not a problem, I just saw us drifting away from what I was asking, and that is, colour "standards", if they even exist. I note a good degree of colour conformity across larger telescope establishments, and that is what I try to standardise mine on (some images OLD).

[Octane (Humayun)]

The way I (and, a lot of us) look at it is from an artistic standpoint and not from a scientifically-correct one.

Produce what looks good to your eyes. As long as it's within reason. i.e., you don't turn pinks to purples and blues to greens, and, so on.

I personally consider astrophotography an artistic pursuit.

Don't worry about getting too caught up in correctness.

Of course, if you really wanted to, you'd go down the monochrome CCD path and then colour balance your images with a known G2V star.

H

[technofetishism (Nick)]

heh, just had a mental image of an mosaic of an Andy Warhol style set of images of M42 then

[naskies (Dave)]

Here's a good primer on the topic:

http://starizona.com/acb/ccd/advtheorycolor.aspx