Coma corrector advice

[Endolf]

Hi, I've got a Baader MPCC MKIII which I've been using with my ASI1600 on a TS Optics Photon 200/1000 (GSO rebranded as I understand it). I got a QHY269M and was using it fine with my other scope (SharpStar 61 EDPH MKII). I've now tried the new camera with the my Newtonian and found that the corners of the images are not corrected. I've eventually managed to improve it by adding 1.8mm of spacers, but it's still not corrected. The baader MPCC is cheap, so I have been looking for a better coma corrector. I've seen the SharpStar 1x coma corrector, and having already got sharpstar gear I am tempted. Does anyone have any experience with this corrector?, is it a rebrand of something else?

Any advice welcome, including alternatives.

Thanks

[michael8554]

If the stars are elongated radially from the centre of frame, then the FF is too close.

The normal MPCC spacing is 55mm with the slim lockring, or 57.5mm without.

Michael