StarTools

I use a Color OSC. I've been considering some of the added detail in images I've seen posted in various places online. I would like to practice following the instructions for adding Ha to an LRGB image, but as I don't yet have the equipment to capture Ha I've been looking for some downloadable datasets online. The closest I've come is a link here on this website to Jim Misti's website. I was trying to use Jim's data set for NGC7000. For whatever reason, I can't get a good image, it is probably me, but I began reading pertinent postings here which indicated that the Ha file be calibrated and stacked with great precision or issues might arise. I'm looking to get a known good LRGB dataset, along with a corresponding Ha dataset to practice with. There are links here and there on the web, and some here, but there are many invalid links.

So, does anyone have, or know of a place where I can obtain a good dataset for LRGB & Ha?
Thanks in advance!

Regards,
Troy

Well in addition to the Misti site there's also the big CN thread linked from the ST page, maybe even HST files?

For practice though, just about any decently-stacked and registered sets with sufficient integration should do.

Depends what the goal is, I suppose. To me, I see three main reasons for adding Ha to LRGB. One would be knots of Ha in galactic arms, just about any large or medium galaxy should do. M31, M33, M81. Another would be enhanced Ha nebulosity to a visual spectrum image. M78 with Barnard's loop is a good call there. Finally there's more full field Ha nebula with RGB stars. Plenty of candidates there.

There's other stuff too, perhaps more fanciful, such as trying to use Ha as a luminance base for visual coloring.

NB Accent is tailor made for much of the more "normal" Ha + LRGB usage.

California Nebula may not be the best dataset for practicing such things. Maybe for narrowband Ha plus RGB stars? It can look decent in SHO, and of course there's a ton of Ha, but not a whole lot of OIII or, IMO, otherwise much of visual spectrum interest to be doing a NB+BB combine.