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IR instead of R channel?


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If you want to. The likely issues are that the CCD response is generally falling off quite rapidly in the I-band, and many apochromatic refractors are generally only well-corrected in the visual bands and so may give soft stars in the far red as the colour correction diverges.

Neither are universally true - e.g. the Kodak KAF- series CCDs used in things like the SBIG ST10XME have good sensitivity out to about 9500Angstroms, and the Takahashi FSQ also is well corrected in the near-IR.

What did you have in mind? Professionally much of what I do is in the I- and J/H/K-bands, so i'm curious.

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I'm a novice ask me in a couple of years, but in the meantime I think it does offer an alternative that may suit certain conds./ colour preferences etc

Below is an RGB crop from the same data as earlier again r& Ready but you decide if there is any discernible difference/benefit


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True, but then I dont think you would get color image out of IR G, as you need B channel. However, with Ir GB you have all the ingredients

I'd try shifting them all over by one, i.e map I -> red, R -> green and G -> blue, you'll end up with an odd colour balance but NASA et al. do that too and it might work well. Will be different, anyway.

By dropping R I think you're fixing a problem that isn't really there, as you're keeping the channel that's worst affected by seeing (:o, losing one that's normally pretty good ® and replacing it with one that'll be noisier due to the drop-off in CCD response (I).

Edited by Ben Ritchie
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Ir-RGB is much better (for planetary), and for example Ha-RGB for some DS imaging. On Jupiter IRGB will make some clouds green. Light green with Pro Planet 742 and much more green with Pro Planet 804 - and you need veeery good CCD to use Pro Planenet 804 at f/20-28 :] So color balance and sensitivity are an issue here.

You can find some IR-IRGB images on web page.

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