My first light shot of Rosette with new narrowband filters

[Josh Lake]

We just installed a new set of SII, Ha, OIII filters for our observatory, and I got first light with them two nights ago. After a day of processing in between chasing the kids around, we got our final shot (first draft):

http://i.imgur.com/ca2tI.jpg

Setup: Tak FSQ-106, SBIG STL-11000, Astrodon 5 nm filters.  4 x 20 minute subexposures (5 in Ha).

I'm thrilled, and this is the best image I've taken yet hands down. I processed it almost entirely in PI and learned a lot in the process. I can't wait to try with Juan's pixel math palette as seen in the 'Hardcore Rosette' thread in these forums (the best shot of Rosette I've ever seen, BTW).

I'd love some feedback on the stars in particular -- the red halos on most come from the red Sulphur channel. Should I run a morphological transformation on them before doing the channel combination?

Any other feedback or advice is appreciated! Today is essentially my 1 year anniversary of using PI and it's been my best year doing astronomy yet.

[Lex]

Hi jlake,

i really like this version of the Rosette!! Nicely done, especially first time with NB filters!
Perhaps you can try to use the SNR to reduce the red touch a bit, you have to try if this works..

Cheers!!

[Josh Lake]

Can you elaborate? Do you mean Signal/Noise Ratio? Or a tool that I can use to selectively adjust the red channel?

Thanks!

[pfile]

probably meant the "SCNR" tool, subtractive chromatic noise reduction.

[Lex]

Jlake, pfile,

Exactly, that's what I meant 

[Josh Lake]

Oh, yes, SCNR, of course! Thanks. Silly of me for not picking up on that...

[pfile]

i dunno what it is about the narrowband filters, but it always seems like one of them has fatter stars than the others. i guess the stars are brighter at particular wavelengths, make sense.

i suppose you could deconvolve the red channel only, or more agressively, to try to tighten down those stars. or, as you suggested, MT on the red channel data would probably help.

[Lex]

That's a good idea to, killing the problem after it's birth 

[Jules]

Lovely Image, I do like NB imaging.

Best Regards

Julian