Spec Sheet
Configuration Overview
Applications/Configurations
Spectrometer Options
Manual

• Up to four independent channels (CCD spectrometers) for measuring up to four light-field quantities (irradiance or radiance) nearly simultaneously.
• Several spectrometer configurations offer wavelength ranges from 300nm-1000nm and pixel resolution from 0.30.
• Sophisticated controller is easily programmed for autonomous data collection (e.g., moorings) or communicates with external computer.
• Built-in auto exposure and dark correction plus radiometrically calibrated output.
• Up to 512 MB of nonvolatile flash memory for internal logging.
• Rugged and versatile fiber-optic cables and light collectors provide enormous flexibility.
• Submersible to 200 meters and includes accurate depth sensor.

• Ocean-color remote sensing - Measure above and in-water remote-sensing reflectance.
• Primary productivity - Measure spectral scalar irradiance in situ.
• Ocean-optical research - Measure profiles of any light-field quantity.
• Environmental monitoring - autonomous or integrated with a mooring
• Benthic optical properties - Can be diver operated for measuring the bottom reflectance and the transmission of light through benthic canopies.
• Any application requiring the measurement of absolute (calibrated) radiometric field quantities with high spectral resolution.

The HydroRad is a revolutionary advance in field radiometers. Competitively priced, the HydroRad includes up to four CCD spectrometers in an acetal plastic pressure housing. The housing and fiber-optic cables are pressure rated to 200 meters and the HydroRad includes an accurate depth sensor. The spectrometers receive light from a specially designed fiber-optic cabling and connector system that is extremely rugged and radiometrically stable. Three types of light collectors can be used to measure plane irradiance, scalar irradiance, and radiance. The complete HydroRad system is calibrated in absolute radiometric units for both in-air and in-water measurements.

For an overview of the HydroRad's many configuration options click here.

The standard spectrometer option measures the range from 350 to 850 nm with 0.30 to 0.35 nm pixel resolution, while the high-resolution composite-grating spectrometer option measures the range from 250 to 1100 nm with 0.40 to 0.45 nm pixel resolution.  Both options collect data from all spectrometer channels simultaneously.  For more details on the spectrometers, click here.

The HydroRad-E1, shown at left, and -E2 include one embedded planar irradiance collector.  HydroRad-E2's also include a collector on a fiber optic cable, which extends from the bottom of the unit.

The HydroRad is completely self-contained and can be operated manually, autonomously, or via an externally connected computer for real-time data collection and display. A sophisticated embedded controller powered by internal rechargeable batteries (or powered externally if desired) performs all of the functions for operating and collecting data from the spectrometers. The controller is programmed to seek optimal integration times depending on light levels, automatically correct for dark current, and radiometrically calibrate the output data. It has many other sophisticated programming functions for autonomous operation.

Multiple HydroRads (with optional daisy-chain ports) can be daisy-chained together to form a virtual instrument of up to 12 channels.

The fiber-optic design available with this field radiometer offers many advantages over traditional field radiometers. The relatively small light-collectors, for example, can be located away from the HydroRad housing to minimize self-shading and to provide the ability to measure light in a variety of configurations. For remote-sensing applications, we offer two innovative accessories, a fiber-optically tethered buoy for measuring both above surface and below surface irradiance and radiance, and an extendable wand designed specifically for holding the fiber-optic collectors for measuring above water downwelling irradiance and upwelling radiance.

Standard embedded collectors are Planar Irradiance. However, Radiance collectors may be substituted. Standard Fiber Optic Cable length is 3 meters - lengths up to 100 meters are available.  Customer should specify collector type for each fiber optic cable.

To see examples of HydroRad configurations designed for various applications, click here.