Playing with duoband colors - and sooo many stars!

[dx_ron]

As the Milky Way starts coming into view again, I've started imaging the Tulip Nebula with the AT130EDT + L-Ultimate 3nm duoband filter. Not finished yet, but with 9.5 hours and clouds, moon and an upcoming trip I started playing around with processing.

There's a lot to play with at Optidev time, between highlighting the tulip shape vs stretching the other Ha parts and trying (or not) to maximize visibility of the mostly Oiii bow-shock from the Cygnus-X1 black hole in addition to the pink v red Ha axis.

Here is the basic default color settings after a stretch focused on the tulip shape:

Tulip_Lu_115x300s_bicolor-default-pink.jpg (497.58 KiB) Viewed 5261 times

It turns out that quite a lot of the "problem pink" can be dealt with simply by maximizing Dark Saturation:

Tulip_Lu_115x300s_bicolor.jpg (484.3 KiB) Viewed 5261 times

[dx_ron]

I also tried separate mono processing of the Ha / Oiii (separating the channels in Compose), followed by RGB/RGB Legacy recomposition:

Tulip_Lu_115x300s_Ha-Oiii_test_v1.jpg (499.71 KiB) Viewed 5260 times

and

Tulip_Lu_115x300s_Ha-Oiii_test_v2.jpg (489.52 KiB) Viewed 5260 times

I like the colors best that way, though some brightness tweaking will be needed. One problem is that making any change in how the colors get balanced requires reprocessing one (or both) channels from scratch.

I do not plan to try to coax sky blue into the center of the main nebula, as many do on astrobin. Yes, that is where the Oiii signal is strongest - but it is also where the Ha signal is strongest.

[lots of work to do on stars, and I did not bother to try to be consistent across these images]

[Mike in Rancho]

Pretty cool! As I was going down the set and things became darker and more red saturated, I was thinking myself that getting white back into the core would probably look the best. And the last image got there!

Heavy star field though, gosh. So maybe that could be pushed back just a bit in the final, whilst retaining the target as-is. Perhaps some usage of SS, or adjustment of black point more or less?

[dx_ron]

Crazy how many stars there are in the Milky Way, ain't it? Yeah, something will need to be done. I collected about 1.5hr of OSC stars for it, also. Hope to gather a bunch more duoband time next moon cycle, when it will be high enough at full dark to not have to find any filler target.

[dx_ron]

17 hours of duoband now, and 2 hours of OSC stars.

HOO, with R and G/B processed separately as mono, then combined using RGB/RGB Legacy:

Tulip_HOO_Ha_v3_12_shrink-dim_SS-50_NR+Oiii_v3_HDR_shrink_iso_NR+OSC_v3.jpg (661.6 KiB) Viewed 4761 times

and "HxO" (nothing loaded into the green channel):

Tulip_HxO_Ha_v3_12_shrink-dim_SS-50_NR+Oiii_v3_HDR_shrink_iso_NR+OSC_v3.jpg (679.08 KiB) Viewed 4761 times

The stars look kind of OK when the image is viewed as a thumbnail, but go to full size and there's an endless number of equally dim stars (the work of SS and Shrink) pretty much obliterating the fainter parts of the nebula.

Should I resort to <gasp!> starnet?

It's all an interesting exercise, what with having to make a new file with reprocessed Ha and/or Oiii mono for any tweak to the balance and stretch.