E194 Other Functions and OptionsWiper operation varies according to the mountedaccessories. Refer to the operation manual of the accessoryto use.* (NOTE)• Do not operate the wiper with dust, oil, foreign obstacles stainedon the glass surface. Otherwise, the glass may be damaged.Completely clean the glass before operation.• If the wiper is operated in the low-temperature environment or forwiping snow, condensation may form on the glass.• Do not operate the wiper in a dry condition without moisture.Otherwise, rubber blade deterioration or incomplete wiping mayresult.• Replace the rubber blade when worn, deformed, or damaged, orwhen incomplete wiping occurred. Contact your Canon dealer.• To use the wiper manually, set the power switch of the wiper to“OFF”.Do not manually use the wiper while it is turned “ON”.4-5 Nitrogen Gas Filling(Option)To prevent fog or condensation on the internal surface of thelens, you can fill the lens barrel with nitrogen gas.Nitrogen gas should be refilled at the periodic overhaul, andbefore the critical event.* (NOTE)To refill nitrogen gas, gas canister and filling tool are required.Contact your Canon dealer or your Canon sales representative.4-6 Zoom Control SelectingSwitch(Only XJ27x AF and XJ27x)Either the speed servo or position servo can be set as theservo system from the analog zoom demand. This setting isperformed using the zoom control selecting switch.Setting steps1 Remove the lens shroud from the lens body.2 Set to the servo type using the zoom control selectingswitch.3 Upon completion of the adjustment, mount the lensshroud on the lens body.Zoom Control Selecting Switch“SPEED” position (left side):Speed servo (default)“POS.” position (right side):Position servo* (NOTE)• Similar setting options to the zoom control selecting switch arealso equipped on the information display, however only the statusof the servo system is reflected on the display. For that reason,the setting can not be performed on the information display.• With “POS.” selected, operation can not be performed from thedigital zoom demand.