the core of M42 seems to be well, but the stars at periphery have much coma. The DSS will not work well with these images.
It seems projection from an ocular, and a better position of the camera with centralization of M42 on the field of view should solve your problem with DSS.
you can verify with star test. But your photo shows stars near M42 with a good round shape.
Any reflector has some coma at periphery. If the field of camera is centered in the edge of field of telescope, you will see much coma. The camera must be centered with the field of telescope to capture the best image.
The image at center of field of the telescope and the image at center of field of sensor of the camera.
