Just an update: I have been out with the RASA on two nights so far – 11th and 13th – and not yet had trouble with dew forming on the corrector plate – even in the absence of a shield. Hiwever, neither was a wet night (it was -1C and -5C respectively) but there were hard frosts (really hard last night). Will update again when I have used it on a night when water is running off the mount or pier.
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