The PR-521 (PR-525 and PR-523) system combines illuminance (with PR-525 - utilizing true cosine correction) and luminance (with PR-523) measurement capabilities - unique for handheld photometers and colorimeters.

The system adds color (CIE 1931 xy, CIE 1976 u'v', Correlated Color Temperature and dominant wavelength) to the list of capabilities. The PR-521 lets you add up to six sets of color correction factors to maximize accuracy when measuring exotic sources.

To make Continuous Measurements, simply press and hold the measurement button. Results are displayed instantaneously - no detector integration or dark measurements to wait for.

A special Peak/Valley data locking feature lets you display the largest (Peak) or smallest (Valley) value during a continuous measurement sequence.

Use the Delta capability to automatically calculate the photometric and color differences between two samples.

Accurate measurements of pulsing or repetitive sources is assured with the SYNC feature of the PR-521. The instruments can be instructed to automatically detect the rate (20 to 400 Hz) of the sample and adjust the measurement acquisition accordingly. You can also enter the frequency value manually.

Instruments can be controlled from a PC using the Remote Mode command language by sending and receiving ASCII text instructions over a virtual COM port - standard equipment with the PR-521.

A rechargeable Li-ion battery means portability - up to 12 hours on a single charge.

A built-in USB Interface lets you connect to the outside world.

Save thousands of measurements on the Secure Digital (SD) card.

PhotoWin 2 Windows software can be used to control the PR-521 systems to provide a powerful and easy to use graphical user interface (GUI) for:

• Instrument set-up
• Standard (luminance / illuminance / color), Reflectance, Transmittance and Contrast Measurements
• Save measurements
• Print Results
• Export to Excel
• Chart Intensity vs Time