IC5070 - Pelican - Narrowband

[OzDave]

About a month ago I captured some Ha frames of the Pelican nebula but didn't manage to get any OIII or SII due to the moon phase and other factors. Finally this month I managed to get the remaining narrowband frames and I've worked this up into an LRGB composite. HA is the L channel, while RGB is composed from a blend of SII and Ha (Red), a blend of OIII and Ha (green), and OIII (blue). There are 11 Ha frames of 20 mins and 7 frames of 30 mins for OIII and SII. Just under 11 hours total integration time. Processed in PixInsight.

Full scale image is on Astrobin (here).

[swag72]

Looking good Is that a gradient bottom left corner?

[OzDave]

Looking good Is that a gradient bottom left corner?

I suppose it could be a gradient, but I did do Dynamic Background Removal in PixInsight, so it ought not to be. I was trying to convince myself that it was simply how the California Nebula (or part thereof) looked. It is difficult to do DBE on this image because actually most of it is nebula and there is not a whole lot of background to use as reference.

I actually need to reprocess this anyway since the OIII and SII have only been calibrated with 3 darks (couldn't wait to get more). But now I have the full compliment of 15 darks done I should really go back and recalibrate. I can look for a gradient then.