Too few frames. Noisy background

Object IDNGC 1579
Perseus
DetailsMag. 5.9
Size 12′ x 8′
Telescope250mm f4.8 Newtonian
MPCC
CameraQHY168C @-15°C
IDAS P2
Exposure(s)17x240s
10/50 gain/offset
darks, flats, bias
CaptureNINA
ProcessingAPP, Photoshop, Topaz DeNoise AI