CE318-T – Sun Sky Lunar Multispectral Photometer

The CE318 is the reference for automatic multispectral atmospheric photometry.
Developed for the NASA in 1992, it was constantly improved to meet the growing requirements of AERONET (AErosol RObotic NETwork), the worldwide federation of networks dedicated to the measurement of atmospheric aerosols and federated by the NASA. Other independent networks like SKYNET, CARSNET, and SONET also operate CE318 photometers.

The latest version, the CE318-T, takes advantage of cutting-edge technologies to improve metrological performance and facilitate operations. AERONET decided in 2015, after full validation, to accept only the CE318-T for new photometers entering the network.

The CE318-T performs sun, sky and lunar light measurements, for the retrieval of essential physico-optical parameters: Aerosol Optical Depth (AOD), Volume Size Distribution (VSD), complex refractive index (n), shape factor, water vapor content. The high sensitivity tracking, detection chain and internal data processing result in enhanced measurements. Flexible communication and solar autonomy allow easy operation both on fixed sites and temporary locations.


Key Benefits

  • Full autonomy with low power consumption (5 W solar panel)
  • Day-time (SUN/SKY) & night-time (MOON: from 1st to last quarter) measurements:
    • AOD, VSD, n, water vapor
  • Several models according to the application:
    • Standard, polarized, BRDF, SeaPRISM (Ocean & Lake Color)
  • High accuracy & long-term stability
  • Flexible communication: RS232, USB, cellular modem, satellite
  • AERONET compatible: fully automated & homogeneous data processing
  • Secured data storage (on SD card)

Package contents

  • 1 sensor head CE318-T (different models according to the applications)
  • 1 collimator
  • 1 cable for sensor head CE318-T
  • 1 control unit CE318-T
  • 1 bi-axial robot
  • 1 tripod infrastructure with enclosure and built-in solar panel
  • 1 wetness sensor
  • 2 x 6 V Batteries / 8.0 Ah in series
  • 1 x 110 / 220 V charger
  • 1 x 3 m cable for connection to a PC
  • 1 PhotoGetData software license
  • 1 flycase for transportation of the whole instrument

Note 1: The user may connect an additional RS232 extension cable to extend the line length. Cimel recommends that the total line length should not exceed 15 m.

Note 2: If the PC is not equipped with a DB9 RS232 connector, the user may use any usual commercial RS232 / USB converter to connect to a USB connector on the PC.

Related solutions

Sensor Head

Full scale digital count precision < 0.1%
Half field of view 0.63°
Smallest scattering angle (from the sun) for sky measurements
Spectral range Si detector: from 340 to 1020 nm InGaAs detector: from 1020 to 1640 nm
Long term drift of single band filters’ transmission rate < 1% / year

Control Unit

Firmware Compatible with all photometer models & all available scenarios
Data coding 32 bits
User interface Touch keyboard
Backlight graphic display
Input & output connectors On a single removable terminal block
Communication outputs RS232, USB, DCP, Hexa-Band (UMTS/3G/W-CDMA), Quad-Band (GPRS)
Storage Flash memory (4 MB): 6 to 8 weeks data storage, for automatic transfers
SD card (8 GB): virtually unlimited capacity security for manual retrieval
Additional measurements Rain detector, GPS, Barometer, Temperature & Humidity sensors (inside of the protection enclosure)
Additional input Thermopile pyranometer (not supplied)
Monitoring Software PhotoGetData Instruments setup, wavelengths selection, scan modes & scenarios configuration, measurement scheduling, data analysis, data visualization, data storage
(raw data, k8, ASCII files)


Azimuth range 0° – 360°
Zenith range 0° – 180°
Tracking resolution 0.003°
Sun / Moon tracking accuracy (automatic active tracking) 0.01°


Temperature range Power adapter (110 – 240 V)
Solar panel 5 W solar panel embedded in the protection enclosure of the control unit
Batteries (backup) 2 batteries 6 V / 8.0 Ah in series

Photometer models

Reference Description Available bands
CE318-TS9 Standard model 340, 380, 440, 500, 675, 870, 937, 1020, 1640 nm
CE318-TP9 Polarized model 340, 380, 440, 500, 675, 870, 937, 1020, 1640 nm / Polarization in three directions
CE318-TU9 BRDF measurements (9 filters) 380, 440, 550, 675, 740, 870, 937, 1020, 1640 nm
CE318-TU12 BRDF measurements (12 filters) 415, 440, 490, 555, 675, 702, 740, 782, 870, 937, 1020, 1640 nm
(SeaPRISM for Ocean Color)
Measurement of radiances emerging from sea water surface 400, 412.5, 442.5, 490, 510, 560, 620, 665, 779, 865, 937, 1020 nm
(SeaPRISM for Lake Color)
Measurement of radiances emerging from lake water surface 412.5, 442.5, 490, 510, 560, 620, 665, 681, 709, 865, 937, 1020 nm


Reference Description Characteristics
15 m cabling PC line kit for 15 m cabling length 15 m RS232 cord
RS232 – USB converter
100 m cabling PC line kit for cabling length up to 100 m RS232 connection kit
100 m special cable (tube cut to length)
RS232 – USB converter
Satellite transmission kit Autonomous DCP satellite transmission system Transmitter, protection enclosure, dedicated solar generator, 2 m mast, anchorage system
Heating robot For operation in freezing environmental conditions Robot with heating (AC mains supply)
10 m cables for indoor installation of the control unit

Environmental conditions

Temperature range Without cold weather option: -20°C to 50°C (in non-icing conditions)
With cold weather option: -30°C to 50°C
Humidity range 0 to 100% RH (in non-icing conditions)

Mechanical Specifications

Infrastructure Tripod, with protection enclosure
Packaging Flycase for transportation
Dimensions (H x W x D) Flycase box: 66 x 52 x 47 cm
Tripod box: 101 x 54 x 54 cm
Gross weight Flycase box: 29 kg
Tripod box: 20 kg

Related Posts



Climate Science Projects
IAOOS - Ice Atmosphere Arctic Ocean Observing System FEBRUARY 2011 - DECEMBER 2019 The IAOOS Project's objective is to develop...
Read More
Sunbelt Spectra comparison with Standard ASTM G173: the Chilean case

Sunbelt Spectra comparison with Standard ASTM G173: the Chilean case

CE318T Photometers Scientific publications Solar
Sunbelt Spectra comparison with Standard ASTM G173: the Chilean case December, 2017 Two spectra of solar direct normal irradiance (including...
Read More
FIREX – AQ Mission

FIREX – AQ Mission

Air quality CE318T CE376 News Projects
FIREX - AQ Mission Approximately half of fire emissions in the US are from Northwestern wildfires and half are from prescribed...
Read More