This is my first major project using my new Antlia ALP-T dual narrowband filter: a 3-panel mosaic on the California Nebula. The mosaic was planned and captured using Zwo's built-in methods in the asiair plus. I only had a single clear night, so I captured 40 x 5 min on each panel and integrated the best 3 hours, for a total of 9 hours integration time. 

As with most of my mosaics, I extracted and processed Ha and [OIII] separately on each panel, then merged into separate Ha and [OIII] mosaics before recombining in HOO1 (i.e., natural colors) and HOO2 (more emphasis on Ha and [OIII] structures, and certainly more colorful!) For HOO2, I used 1.25x Ha and 5.0x [OIII], with the Ha green channel bumped up a smidgen. 

Because there is so much nebulosity at the edges of panels, mosaic processing was challenging in AstroPixelProcessor, but I finally arrived at some good tricks: 
1. Stack and process light pollution for Ha and [OIII] panels separately before mosaicing  
  * Use "reference" instead of "full" during integration, so that you have less junk on the edges. 
  * Take screencaps of where you place your squares for light pollution removal. Match square placement as much as possible on neighboring panels. 
2. To start your mosaic, load your processed Ha and [OIII] panels in separate channels 
3. Standard settings in registration:
  * pentagon pattern recognition, scale 1 to 10
  * use dynamic distortion correction 
  * disable "same camera and optics" 
  * registration mode: mosaic 
4. Use "advanced" and "multiply-scale" in normalization 
5. For integration: 
  * Integrate per-channel 
  * Do *not* use LNC in integration -- it introduces more artifacts than it's worth. You're better off spending more time in 1. If you must use LNC, use first degree, and at most 3 passes. 
  * I used 20% overlap in acquisition, and used 15% MBB blending 

And that's it! 

A: Mosaic in original colors, at half resolution
B-D: Mosaic in adapted HOO, at half resolution (variations of color balance) 
E: Ha mosaic, full resolution 
F: [OIII] mosaic, full resolution 
G: HOO mosaic, full resolution (large file!) 
H: Zoom background 
I: iPhone background