K2 Plus's built-in camera is pretty good, but the internal light coming from the rear right side of the printer creates a refraction in the lens which can be seen as an undesired haze on the picture. See the before and after pictures.

Use a lens hood to protect against this.

Print in PLA at 0.08mm layer height, use a 5mm brim. It took less than 2 minutes. While looking to the live video through Creality Print, attach to the camera carefully, with the hood wing facing the rear light. Adjust until the borders disappear from the image. Enjoy clear picture!