Willis' Astronomical Observations: Unexpected weather of Hehuan mountain

Totally unexpected! The weather last night was so dramatic!!! It started with rain, lightning & thunder. After the rain stopped, the sky was clear! We ran up to a site called 武嶺 at once. In the middle of setting up the equipment, terrible fog came. Savio & I were punished to stand & wait! In the midnight, the sky was clear again. We started the setting again. There were terrible people around & they used torches!!! Anyway, the sky was unstable until 3:00am. I was on the point of giving up, but finally I got everything work!!!! These are my M31 & Double Cluster! I found that when I use the auto Noise reduction in D40, there is a dark band in the lower part of the images!!! In addition, dews were formed in both the main scope & the guide scope. I don’t have any heater to avoid it. So I can just use an air pump to rectify the problem. It couldn’t be fixed completely anyway! The lucky thing is that it didn’t cross my DSO. Otherwise, it wasted my time. Sometimes we really need some luck to take good photos. When the sky is OK, no people & car making any forms of light pollution, there was a satellite crossing my 10 mins M31 photo. Good grief! Well, I posted both cropped & un-cropped versions here. I will not use the noise reduction function in the coming night, unless I fixed the problem.

APM-TMB 80/480
TV 0.8X
LPS-P2
HEQ5Pro LVI I
M31: ISO 800, 600s, single frame, No flat frame, No dark frame (There was a satellite crossed my photo!!! I will make it again!!!)
Double Cluster: ISO 800, 300s, single frame, No flat frame, No dark frame

Double Cluster: The dark band due to 40D's noise reduction