Thread: The Lagoon
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Old 30-09-2008, 03:58 PM
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Peter Ward
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Join Date: Dec 2007
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Quote:
Originally Posted by gregbradley View Post
A fabulous image. Your 14.25 RCOS is awesome.

On the topic of what colour Ha really is, there was a very informative post where I started a thread on Astromart.

Here it is:

http://tinyurl.com/4zrrqj

Glad you liked the image...

I'm not an Astromart member...is there an alternative link?

Despite not having read the discussion....I'd make the observation that it is irrelevant to the colour of H-Alpha discussion as to what a filter *reflects*.

The *transmitted* colour (ie what you eye/sensor actually "sees" ) is everything.

Monitors do not have any pixels "redder" than 620 nm (plus or minus about 10nm).

The brightness (ie amplitude) of a colour does not change its wavelength....hence the best we can do is make LCD/CRT's deepest red (620nm) look a little darker (ie lower amplitude) to try and give an illusion of even longer wavelengths (eg H-alpha at 652nm).

Last edited by Peter Ward; 30-09-2008 at 04:00 PM. Reason: clarification
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