Hi everyone!

I'm working on a 4x4 SHO Panel, following the same workflow I did a few times already. I prefer to create 3 mosaics, one for each filter, and then align and combine them. The problem at the moment is that, for any reason, it seems that my bottom pannels on the Sii filters are 'gaining' a noise that wasn't originally there after I apply the GradientMergeMosaic process.

I'd like to detail below what I'm doing before combining the 3 mosaics, and where I see the problem. This is what the process looks like for each panel of each channel:
  1. WBPP
  2. Cropping
  3. Gradient removal (I use GraXpert)
  4. Background Normalization
  5. BlurXterminator (Correct only)
  6. ImageSolver on each pannel
  7. MosaicByCoordinates for registering the images
  8. GradientMergeMosaic for stitching them all together
  9. BlurXterminator on the resulting image (this time for deconvolution)
  10. NoiseXterminator


This has worked without issues before, as you can see on my Ha mosaic below.

Ha_Mosaic.png

Now, by applying the same process to my Sii images, I see a huuuge increase in noise on the two pannels of the bottom. This is the result of GradientMergeMosaic for the Sii pannels:

Sii_Mosaic_P1P2P3P4.png

If you look closer, this level of noise isn't originally there. Here you can have a side-by-side comparison of the original top left and bottom left pannels, before they are registered and GradientMereMosaic is applied:

Sii_Mosaic_Noise.png

I also experimented by stitching together only the left and then the right pannels separately, and that results in two smoother images (please ignore the fact that I didn't crop or handle additional individual registrations for this experiment, so you have the 'void' on each side of the images below):

Sii_Mosaic_P1P3.png
Sii_Mosaic_P2P4.png

One more thing: I'm mostly applying the 'Average' combination on GradientMergeMosaic, with a Shrink Radius of 8 and a Feather Radius of 10, but I have played around with these settings a bit and the results were very similar (even with 'Overlay').

Any ideas what may be causing these weird results?

Thank you so much!
Moleiro
Like