Last night was something of a rarity: a crisp clear night. And let me emphasize how crisp it was.
I rolled Big Bertha 2.0 out a bit late--around 8:30 PM--and by then, the target that I had originally planned to go after, M101 had dipped too low in the sky for a decent view. After spending some time collimating the mirror, I decided, "It is just too cold out here!" and went back inside.
I am pleased to report that the diagonal mirror holder and mirror cell that I made for Big Bertha 2.0 are very easy to adjust for perfect collimation.