Colour on Deep Sky Objects

[Scosmico]

Hi,

What is the minimum aperture that you need to see colour on Deep Sky Objects?

[ollypenrice]

To all intents and purposes I'd call it impossible. We have a 20 inch Newtonian at a very dark site and I see no colour in, for instance, M42, yet I do see structural detail that looks photographic. It will depend a little on your eyes because some people do report seeing a hint of colour in some DSOs. All I can say is that my eyes would need a good bit more than 20 inches. I saw no colour in M27 in a 25 inch at the Observatoire de Haute Provence, for instance.

Olly

[RikM]

M57 was visually pale blue through a 16" LB at SGL5 last year. That's the only 'colour' I have seen in a DSO other than coloured doubles.

[Odd Dob]

Grey is a colour, isn't it?

[Ags]

Some double stars have nice colors!

[Scosmico]

Thanks for all replies. Appreciated.

[astroeddie]

The Eskimo Nebula and Cats Eye nebula show a very pale blue/green colouration.

Everyone's eyes are different.

Alas they never look like they do in the images. Just the thought of looking at an object for what it is suffices 99% of the observers.

[ollypenrice]

Good point about the small bright planetaries. They do show colour but in terms of structure are pretty much stellar in appearance.

Olly.