I've got a ticket open with QHY support and all they've offered me so far is to increase the offset. I've been shooting gain 10/offset 50 forever and I confirmed that for bias frames the minimum ADU is 4, so I'm not clipping and this seems like an unlikely fix.
Any other suggestions of things to try/check? The attached light frame is 300s with an IDAS NBZ dual narrowband filter - single sub, no calibration, just an autostretch in PixInsight.
![20250209313-scaled[1].jpg](https://cdn.astrobin.com/ckeditor-thumbs/106775/2025/5f547ae5-67f0-481c-ada3-424820846ca0.jpg)