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Alchemy
18-02-2008, 10:04 PM
Hoping for a quick bit of advice, i have bought the astronomic LRGB set for imaging , the Red one looks distinctly orange, particularly compared with the meade red which looks red.
So does this make a difference and how do you (hoping youre experienced at this) blend them just as rgb or as orangeGB ,,, and would using the meade red be any different.

I have not tried them out yet but want to have in mind the correct way prior to joops imminent arrival.

Thanking you for your help:)

iceman
18-02-2008, 10:06 PM
It doesn't matter what colour it looks - it's the wavelengths that it passes through that makes a difference.

Still blend them as RGB.

You may still need to weight each colour when combining, or simply use levels afterwards, to adjust the colour channels independantly. In some conditions, some channels will be fainter and will need more of a boost in processing to even it out.

Ideally, you should set the capture settings so that each colour channel has the same peak in the histogram. This can mean capturing the blue channel at a slower framerate, or using a higher gain. It will be much easier to balance the colours later if you do this.

Great to hear you got the colour filters - what filter wheel have you got?

bird
18-02-2008, 11:01 PM
The astronomik set have carefully matched pass bands. The red filter does let through a bit of orange as well, so the cutoff and slope of the filter matches properly with the green filter.

cheers, Bird

Alchemy
19-02-2008, 07:12 PM
thanks for taking the time to give me the advice i needed, i will keep an eye on that histogram peak, i will run my first results past you when the time comes, your advice on whether i get it right would be appreciated.

i bought the orion multifilter wheel , it holds 5 filters, only the manual turning one, hmmmm probably would help to have a electric focus gizmo

now that ive got the whole filter set im ready.:thumbsup:

iceman
19-02-2008, 10:06 PM
Great stuff C. I've got the same filterwheel, but it's the Atik brand.

I do have an electric focuser - just the Orion accufocus on the normal crayford (not with the fine focus).

Not ideal or terribly scientific/accurate, but it's tonnes better than doing it by hand.