California Nebula NGC 1499

I had just 2 hours clear time the other night so I set up 2 mounts, 2 scopes and 2 cameras and imaged the California nebula.
I combined the data from both cameras to get this image.
It is a color image but I used the HA (red) channel for just luminance and combined the G and B channels in other ways to create a realistic look at the gigantic dust/gas clouds…

Specific Feedback Requested

Any appreciated.

Technical Details

asi294 and asi 2600 cameras, askar 600 f5.6 and Williams 81 gt scopes.
PP in Pixinsight.


This is the standard Hydrogen Alpha edit, hence the name.

You pulled out amazing tonal detail in the monochromatic interpretation, compared to the red version! The detail of the threads surrounding the main object are outstanding!

Thanks Diane… although initially I thought pixinsight overrated, it does things no other software can do… Photoshop for astrophotographers, the more I learn , the more there is to learn…It has routines that just pull all the details that are amazing.

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It is definitely the Photoshop of astro processing! (It comes close to making PS look like a kindergarten coloring book.) I’m getting sucked into the astro thing again (feels like unfinished business that got rudely interrupted 5 years ago by a spectacular wildfire) and starting to dig back into troves of notes that were safely in the cloud.

Great image Dan. HA RGB works well but can be tricky to avoid a salmon color as they call it. I use to use PI but switched to Astro Pixels Processor because it works well and was easy to us. Mainly I get a TIFF to take into Lightroom Classic and Photoshop. A trick I learned back in 2007 with HA RGB was the following. There are 2 images, the RGB and HA. In photoshop split the RGB into each channel. Take the HA and paste in over the Red and Blue Image. Set the opacity to70% and changed blending to lighten. Do the same with the blue but set opacity to 15% . Then combine the channels. What this does is help preseve star color and prevent a pink salmon image. As a last step you can use the HA as a luminance layer and set a mask to hide most of it expect the faint areas. Finally Selective Color is a fantastic tool in Photoshop to adjust the colors as needed. This is what I did for the Sharpless Catalog website I did in the past. You are doing a wonderful job with your astrophotography, I know as I have been in it over 50 years.

Astrophotography sure has gotten easier, @Diane_Miller. A 135mm lens on a inexpensive tracker does magic with the cameras and software we have today. I have shown this to the visitors where I work at Kitt Peak during the overnight program

Quite impressive, Dan. Love the initial post as it has such depth and movement. Wow.