I'm really happy with this result!
I never intended to use the scope I did here for imaging. I got it on a lark, because everyone should own a ridiculously large refractor at some point. Mine was used but essentially NIB, tags still on, because the original owner found it too heavy for them. It's an achromat and visually it does have some evident CA. Still I have fun looking at the moon with it, etc.
Narrowband imaging isn't impacted by CA as long as you can align the images. PixInsight does a great job of this. Is it perfect? No. Did this scope cost what a 6" APO would have cost? Not even close!
This scope also produces a wonderfully flat field when using the TSFlat2 or, as in this case, the Starizona ApexED-L reducer. I may be becoming addicted to the sharp stars out of this refractor and scoffing at my reflectors.
The palette here is one I borrowed from The Coldest Nights: Ha for Red, Oiii for blue, and Green is a combo, preferring Ha where that's strongest and Oiii where that is. Instead of the usual red/cyan Veil image this gives me something with more dynamic range. I like it, anyway!
https://thecoldestnights.com/2020/06/pixinsight-dynamic-narrowband-combinations-with-pixelmath/
Comments