EasyView Big Digit Light MeterThe EA31 measures up to 20,000 foot-candles and 20,000 lux in four ranges with ±3 percent accuracy. This light meter features a compact and rugged design with a large display and analog bargraph to view trends. Additional features include Data Hold, Min/Max, Auto Power Off, and over-range indication. Comes with built-in stand, remote sensor with protective cover and 39-inch (1-meter) coiled cable, protective rubber holster, six AAA batteries, carrying case, and user manual. Model EA31-NIST is also available with a NIST traceable Certificate of Calibration.What Is a Light Meter?A light meter measures the amount of visible light, also known as illumination, in a given area. For many meter brands, including Extech, illumination is expressed in units of measure called Lux (for metric) and foot-candles (used in the US). To use an Extech light meter, the sensor is placed on a tabletop or other surface in the area to be measured and the light level reading is indicated on the meter's display.Various Types of LightingThere are many different types of lighting that can be measured. the most common are: sodium, tungsten, mercury, and fluorescent. The following list shows common applications for each lighting type.Sodium lighting: Highway, parking lots, security measurementsTungsten lighting: Sunlight and incandescent lighting measurementsMercury lighting: Highways, parking lots, stadiumsFluorescent lighting: Indoor lighting for workstations and store display areasMore Extech Instruments to Choose FromEA30EasyView Big Digit, Wide Range Light MeterThe Extech EasyView Wide-Range Light Meter measures up to 40,000 foot-candles in four ranges and 400,000 lux in five ranges with ±3 percent accuracy - ideal for outdoor use. It features a compact and rugged design with a large display and analog bargraph to view trends. Peak mode captures short light pulses to 100µs. Relative function zeroes the sensor or can be used to display the difference from a reference value. Additional functions include data hold, min/max, and auto power off. Comes complete with built-in stand, remote sensor with protective cover and 39-inch (1-meter) coiled cable, protective rubber holster, six AAA batteries, and carrying case. Model EA30-NIST is also available with a NIST traceable Certificate of Calibration.EA33EasyView Big Digit Light Meter with MemoryThis compact and ruggedly designed meter has a wide measurement range to 99,990 Foot Candles in five ranges and 999,990 Lux in five ranges with 0.001 Fc/0.01 Lux resolution. Features include: Store and Recall up to 50 measurements with relative or real time clock stamp, Luminous intensity (candela) calculation, a ripple function that excludes stray light from the primary light source measurement, multipoint average function, timed hold, relative measurement in absolute value or percent deviation, comparator function with high/low alarms, and auto power off with disable. Comes complete with built-in stand, light sensor and protective cover with 36-inch (0.9-meter) coiled cable, protective holster, six AAA batteries, and carrying case. Model EA33-NIST is also available with a NIST traceable Certificate of Calibration.