I just got a Rapid, and adjusting the EV ring which shows the options for shutter speed and apeture for correct exposure is a pianful little piece to use, is this normal on the Zeiss lenses, or it this indicative of gunky works? I've read that the partiular grease/alloy composition used in some zeiss lenses was prone to mold and solidification freezing the whole thing, is this true or applicable to the Rapids?