Being a southern Cali girl where cold is about 60 and hot isn't much more than 90, lol, even northern California's temps push me...summer high is often over 100 and average cold is around 40 with the occasional night down in the low 30's but we had mid 20's a few nights ago!!
The ocean really makes the temperatures more consistent - I lived less then 10 miles away - which is why there wasn't too much range...now we're inland by a couple hundred miles along with being about 400 miles further north - so we get four seasons now - but I am getting more comfortable with it being wider
Having proper clothes helps too!! I'm perfectly happy with 48F
I love it too! It has such character in its shape It is in our "front" yard above our driveway. I can see it from my home office desk and love to watch the deer rest below it and the occasional hawk land in it.
No tracking - just a 20 second or so exposure...there's a thing called the rule of 600 which helps you figure out the longest exposure you can get before you start getting star trails...I'll send you the tips I got from who, if you haven't discovered, is an amazing celestial shooter
There's an automatic shake on the d300, thankfully 'cuz I'm way too chicken to attempt it myself - you've got much more experience with that type of thing...the "local" camera shop (where everyone around here goes and trusts) does free cleanings when I absolutely have to get it done
I change often too, but you still couldn't get me to do it (I remember about your expensive work toys ) I'm not positive how it works, but I think I've got the camera set to automatically clean the sensor every time I turn it on - possibly by vibrating the sensor to knock off the dust.
To check your sensor, find a blue sensor test screen on your computer and take a photo of that at f/16 and f/32. This is wear macro comes into problems. I started to take a photo of the eggs with a D7000, but the sensor was really dirty. The Auto-clean doesn't work. The D7000 is notorious for splashing oil from the mirror onto the sensor. I also clean the mirrors that they say can't be touched.