Calibrate and verify accuracy of light meters, shutter diaphragm operation, or lens carriers, using timing instruments. Disassemble equipment to gain access to defect, using hand tools. Adjust cameras, photographic mechanisms, or equipment such as range and view finders, shutters, light meters, or lens systems, using hand tools. Clean and lubricate cameras and polish camera lenses, using cleaning materials and work aids. Measure parts to verify specified dimensions or settings, such as camera shutter speed or light meter reading accuracy, using measuring instruments. Test equipment performance, focus of lens system, diaphragm alignment, lens mounts, or film transport, using precision gauges. Examine cameras, equipment, processed film, or laboratory reports to diagnose malfunction, using work aids and specifications. Requisition parts or materials. Read and interpret engineering drawings, diagrams, instructions, or specifications to determine needed repairs, fabrication method, and operation sequence. Fabricate or modify defective electronic, electrical, or mechanical components, using bench lathe, milling machine, shaper, grinder, or precision hand tools, according to specifications.