I have recently bought from Hartblei a Kiev 66 Automat slide projector. It seems that the higher is the temperature of the equipment, the harder is the turning of the focusing wheel. Is it wise to put any kind of lubricant on the plastic thread? Which one? A last question, what's the aim of the silver side of a projection screen? Regards, Jose Royo --- Rollei List - Post to rollei_list@xxxxxxxxxxxxx - Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' in the subject field OR by logging into www.freelists.org - Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field OR by logging into www.freelists.org - Online, searchable archives are available at //www.freelists.org/archives/rollei_list