General Tools DLM112SD Data Logging Light Meter with Excel Format SD Card Measures light intensity within 3 automatically switched full-scale ranges - 2,000 lux, 20,000 lux, 100,000 lux (200 ft.-cd, 2,000 ft.-cd, 10,000 ft.-cd) Selectable lux or foot-candle units Performs real-time automatic data logging at sampling time settable from 1 sec to 1 hr.; supports manual logging and changing of card storage location Big (2.5 inch diagonal) front-panel green backlit LCD is easy to read; displays maximum and minimum readings Auto power off function that can be disabled for data logging