Observing Colours in Orion Nebula

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weixing
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Observing Colours in Orion Nebula

Post by weixing »

Hi,
Just wonder anyone had seen colours in Orion Nebula through your scope?? The first time I saw it was through Elton new 18" scope... it was obvious to me. And yesterday night, I realised I can see it through my 8" scope... it was very, very faint... just a hint of it, but I'm quite sure that it's there.

Most part of the nebula was greyish and may be a bit greenish/bluish, but I saw yellow and red on the edge of the band of nebulosity between the Trapezium (Theta-1 Orionis) and Theta-2 Orionis. The edge is divided into two band of colours: reddish/pinkish on the side nearer to Theta-2 Orionis and yellowish on the side nearer to the Trapezium. The yellowish is a bit stronger and easier to see than the reddish/pinkish.

After some experiment, I realised that I can only see it at low magnification and using direct vision: I only saw the colours (just a hint of it) at around 48x (using the Orion 21mm Stratus) with my 8" scope using direct vision... using averted vision, I saw more nebulosity, but no colours. I also remember the colours was obvious in Elton's 18" scope when he use his Pentax 30mm XW which give around 64x, but become very faint when he use a higher power eyepiece (can't remember the focal length).

Anyway, I check with Elton and he can't confirm to see the colours in the nebula and ask zackae to confirm my observation last night when he join me later, but he also can't see the colours. So may be those with scope 8" and above can check whether can you see the colours... Just to confirm I'm not night dreaming... :P :P :P

Have a nice day.
Yang Weixing
:mrgreen: "The universe is composed mainly of hydrogen and ignorance." :mrgreen:
JJLoke
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Post by JJLoke »

i was able to see the orion colours as well using my 3" scope at 19x zoom. it was redish-pinkish-purplish and a slight tint of blue. Same effects using tak 4". 6" and 8" gave more colours like yellow and grey at the core and sides, but the prominent colours stated earlier did become fainter when zoom was pushed higher, but the nebula cloud yelowish grey was more obvious

the 4", 6" and 8" are my club's scope
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swimaniac
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Post by swimaniac »

I was observing from the carpark at my place and I did not see any colours on my Meade 8" SCT at 62X and 100 X. Colour was grey only.
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Tachyon
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Post by Tachyon »

Two possibilities:

1. You actually did the see the colors

2. Your brain somehow managed to fuse the color image of Orion in your memory with the 'monochrome' image you saw (remember, this is not unusual, in a semi-dark room, look at a familiar object which you know the color well, and you will see a tint of the color.)

Whatever it is, just enjoy it!
[80% Steve, 20% Alfred] ------- Probability of Clear Skies = (Age of newest equipment in days) / [(Number of observers) * (Total Aperture of all telescopes present in mm)]
elton
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Post by elton »

Actually I can confirm that I saw some colour on M42. Not the red though. There was a lot of contrast in the big scope with a greater variation of brightness in the different parts of the nebula. At the bright leading edge which I think Weixing pointed out, the grey/green gave way to some yellow. It you think about it, grey-green and grey-yellow are very close, with the yellow areas found only the bright leading edge.
If our eyes are most sensitive to green then it makes sense that the non-green areas are only found in the brightest parts of the nebula.
Looking forward to see the reds. Hopefully get to bring this to a dark site soon.
elton
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Re: Observing Colours in Orion Nebula

Post by elton »

weixing wrote:
After some experiment, I realised that I can only see it at low magnification and using direct vision: I only saw the colours (just a hint of it) at around 48x (using the Orion 21mm Stratus) with my 8" scope using direct vision... using averted vision, I saw more nebulosity, but no colours. I also remember the colours was obvious in Elton's 18" scope when he use his Pentax 30mm XW which give around 64x, but become very faint when he use a higher power eyepiece (can't remember the focal length).
I think this makes sense too. Lower power = larger exit pupil = brighter image. Colour receptors in your eyes need more light to be activated.
JJLoke
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Post by JJLoke »

in the dark, ur eye's rods and cones (perception of black, white, gray and grayscales) are fully activated. increasing magnification reduces light intensity

hope someone can give some light on eyepieces exit pupil and focal length, hows it affect light output and onto the dilated pupil. i read it before somewhere but could not remember clearly.
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wucheeyiun
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Post by wucheeyiun »

i see a tinge of green in m42 from the mewlon ... :)
will like to a peek at elton 18"
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cataclysm
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Post by cataclysm »

see a tinge of green in m42 from the mewlon ...
Yes agree with Cheeyiun, did notice some green in the nebula with the mewlon, I guess you will see more on a bigger scope.
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Post by Robin Lee »

I can obviously see that it's green through my 8" SCT.
Clear skies,
Robin.

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