Dark frames question

[libraryman]

I didn't have chance to take dark frames after obtaining my light frames before daylight came so i tried to take the dark frames later; cooling the camera in the fridge to a tempreture that i thought was appropriate

I'm not sure of the tempreture i shot the lights at and if i'm taking the darks at a lower tempreture than the light frames, would this have a big impact on the historgram of the final stacked image.

i tend to see the Data well over to the 0 point of the historgram and possibly clipped, i'd appreiciate a clue as to why my data appears this way.

R

historgram.pdf