When does processing go too far?

[ollypenrice]

Correct, though, in what terms and to what purpose? My aim is to get the star looking small, tight and the right colour.

Olly

[themos]

Here's a "smaller" question: Should we colour balance so an A1 star looks white or a G2 star?

[Steve]

I have been wondering.

We know from experience that only a handful of targets display colour to the naked eye (i.e. Betelgeuse, Jupiter and Saturn). But, what if we could actually travel closer to, say, M42. Would we see the colours shown in images like the one posted by Olly here in this thread? Or would our eyes still not have enougth sensitivity to see anything other than shades of grey? I would like to think we would at least see hints of colour, but I really don't know?

[RobH]

I would guess that you'd see colour in the regions close to you.....this is hot inonised gas in some cases, just a long way from us, hence very faint. I may be completely wrong of course

Rob

[Psychobilly]

maybe...

nebula - How dense are nebulae? - Astronomy - Stack Exchange

[Ags]

I think you would see no more color than through a telescope using a magnification that gives the maximum exit pupil for your eyes: that is showing the image larger/nearer at the maximum brightness your eyes can manage. As I understand it, surface brightness does not decrease with distance, so even if Orion filled the sky you would not be getting more photons per square arcsecond.

Another problem would be the stars lighting the nebula would also be closer and brighter, so the best bits of the nebula would be lost in glare.

[themos]

The only way to see colour would be to make a weird "telescope" that somehow added all the light from ten thousand 8-inch f/6 newtonians, resulting in an effective f/.06 instrument but with a 4mm exit pupil.

[themos]

The first operation on a person's retina to enhance it to the point of seeing colour in nebulae will happen sometime in the 2060s.

[rfdesigner]

The only way to see colour would be to make a weird "telescope" that somehow added all the light from ten thousand 8-inch f/6 newtonians, resulting in an effective f/.06 instrument but with a 4mm exit pupil.

When the Subaru telescope was built an eyepiece was specially commssioned to allow opening dignitaries to actually look through it.

Apparently the views were out of this world.. colours were visible.

Telescopes — National Geographic Magazine

Derek

[ollypenrice]

I don't think going closer would necessarily help. You widen the field of view occupied by the object and so observe an ever diminishing density of gas and, therefore, saturation of colour. Wandering around inside M42 you'd see nothing but stars because the gas is really so tenuous. There is an optimum FOV, I suppose, in which the object fills the retina in whatever instrument (or no instrument) in use. We do indeed need a hypoerfast visual tleescope with tiny exit pupil. Don't just stand there, Themos, DO something!!!

Olly

[RobH]

I can see that you wouldn't see colour in something large and tenuous like M42 for the above reasons, but I'm pretty sure that you'd see it in the early stages of a planetary nebula, and certainly early on in a supernova explosion...in both cases the light is emitted from a pretty localised area and will be bright....very bright in the case of the SN. Obviously it all depends on the distance of the observer of course.

[Earl]

No "Wrath of Khan" style clouds to play cat and mouse in !

[RobH]

No "Wrath of Khan" style clouds to play cat and mouse in !

What....you mean it wasn't true

Khaaaaaaaaan !!!!

[barkis]

I have read somewhere, that if a one inch core of the Orion Nebula was taken, and I think the distance mentioned was 40 light years, the total weight of the material would be equal to a twopenny piece. So tenuous is the neb.

Ron.

[ollypenrice]

I have read somewhere, that if a one inch core of the Orion Nebula was taken, and I think the distance mentioned was 40 light years, the total weight of the material would be equal to a twopenny piece. So tenuous is the neb.

Ron.

...and I used to trot out what I've read several times in books, that the density of the Great Nebula is less than can be acheived in the best laboratory vacuums on earth. But then a Manchester University academic who visits regularly said, 'Ah, not any more!! We have recently built... ' But M42 is still only marginally denser than nothing!

Olly