How much smoke is normal?

Before any of the trater boys start piping up, no it's not on fire!!

How much smoke is normal when it's warm and just ticking over? I noticed tonight that when sitting ticking over I'm getting some White/grey smoke up the rear window. rear dimmister not on, so it's not that.
When I apply some throttle, I get more smoke, but after coming off it dies back down again.
Not loosing water, and I'm pretty sure the small oil I'm loosing is coming from the rocker cover gasket.
I'm a little concerned.

tis condensation from exhaust - coz of cold wevva