Cooling down time

[tommys]

I'm new at this and have just got a Skywatcher Explorer 130P. I understand it should be left outside to cool down. How long should I leave it before using it?

[Kevdan]

Good question , I have ordered the exact sam escope and was going to ask this as well as about 2 million other questions,

[Moonshane]

it really depends on the difference in temperature and also the magnifications you will initially use. eg. if you go from a warm house to a -2 outside garden then it will take longer to equalise. you can start to observe at low magnifications much more quickly than at high magnifications.

BUT effectively ignore all the above as you could estimate at around 5 minutes per inch of aperture. your scope is about 5.5" so just about half an hour should be OK. if you can leave it longer then even better. a small fan can help but is not really needed at your aperture.

I usually take the tube outside, then start setting up, line up the finders, find my coat, hat etc and do a brew and then it's nearly half an hour anyway!