Edit: Alternate process after feedback:
Lossless version is here:
https://flic.kr/p/VJHTXv
Original Post:
Just before the full moon this month I was able to get out and try to sort out the spacing required for using the 0.6 reducer with the Sharpstar 107PH. I've discovered that I do not quite have the correct combination of connectors/spacers to be correct, but I'm getting close. Although the (rotated) image has been partially cropped to remove some vignetting, I've left some evidence of the spacing issues in a couple of corners (near the top of the view).
I think to get the best out of this reducer, even if I ever sort out the spacing properly, I will need to eventually go to larger filters - the 1.25" vignette too much. I think I lose about 15% on the widest axis.
Larger view without the jpg compression:
https://flic.kr/p/VCCevg
The details:
Sharpstar 107PH with a 0.6 reducer
ZWO ASI1600MM-C at -15C, Unity settings.
Ha 13 x 180 sec
OIII 12 x 180 sec
SII 12 x 180 sec
Darks and flats applied.
Processed in PixInsight.
In what seems to be a reoccurring theme for me, the imaging session was interrupted by clouds and so this is all I was able to get.
Feel free to give feedback, etc. There's one feature on the image that I'm still trying to find out more about (as in if it's real or some strange artifact). Near the top far right of the image, you might be able to see a small mostly blue "circle". It's outside the main nebula, above 2 brighter stars, maybe about 1/6th the way down from the top. You might need to look at the larger version to see the feature. Any ideas what it is?