Great info thanks all.
In retrospect I did everything wrong. Applying my novice thinking that a telescope would work best if its temperature matched ambient, I put it outside at dusk. When I went out at 10pm I was surprised (and a bit concerned) to find it covered in dew! haha ... guess this is called 'learning curve'
Anyway I wiped it dry, remove OTA cap and aligned. With OTA pointing at Moon/Mars soon enough the pupil (if that's wot its called?) was misty .... now I know it's better to keep OTA warm!
I'm going to add heater + shield, plus have a hair dryer handy.
I'm not up for painting it white ... well yet anyway. But interesting point, I guess that's why so many pro scopes are white.
cheers