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Rob_K
30-11-2015, 10:12 PM
Stupid name for a planet! :P In a sense, what I've done here is a pointless exercise because we know that Uranus is a cyan colour and we know that when we split the light from Uranus we get an optical spectrum like the one I posted in the previous thread.

On the other hand, all I actually got was a Zero Order image of Uranus as a pure white over-exposed blob, and a low-res optical spectrum. You should be able to sum the spectrum to show the visible colour of Uranus. All I did was compress the bar spectrum of Uranus down to one pixel in width using Photoshop. This effectively averages the colour but produces a dim, dark colour representation, not helped by the spectrum being a little under-exposed. To increase brightness and intensity to complete the 'summing' I applied levels and saturation, somewhat arbitrarily but hey! ;)

My processing skills are somewhat Neanderthal and I'm sure there'd be better ways of summing the spectrum (but hopefully not returning to the white of the over-exposed Zero Order image!).

Cheers -

Somnium
30-11-2015, 10:13 PM
it''s better than George !:)

robin_astro
01-12-2015, 03:54 AM
Hi Rob,

Unfortunately gratings are not equally efficient at all wavelengths (The efficency of the blazed Star Analyser grating peaks at ~500-550nm in the green and drops off into the red and blue) so summing the light in the spectrum without correcting for this will introduce a colour cast. (The zero order contains most of the rest of the light missing from the spectrum and usually appears red-ish if not not overexposed)

Robin

billdan
02-12-2015, 01:46 PM
Reminds me of an episode of Futurama, where the Professor says "we changed the name to Urectum because of complaints"

astronobob
03-12-2015, 12:19 AM
Nice one Rob, interesting in deed , , :thumbsup:
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Not only did 'U-Rec-tum' --you very near 'Killed-tum'

:scared3:

ralph1
05-12-2015, 05:06 PM
The 'levels raised' version looks the closest to how the planet looks visually.

Pi-Eyed
19-12-2015, 01:23 AM
What's wrong with George?

:shrug: