Perfectly normal to see a light misting when the ambient temps are low & humidity high. Should clear on it's own, once temps rise & humidity lessens, through the lamp units breather. Failure to clear can sometimes mean the breather has blocked, which may need investigation. A crafty solution, if it worries you, is to drop out the bulb, in a dry garage preferably, then dry out the unit with a hairdryer using a warm setting. Once clear make sure you switch the hairdryer to cold, so the lamp unit it brought back to ambient temperature. Replace the bulb & off you go
However, persistant water droplets on the inside of the lens is quite another matter, maybe a crack or leak somewhere.