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Developer: Leiden University (hardware, software), DDQ (software), Bright LED solutions (hardware, external partner)
Contact: Olivier Burggraaff:
Supporting materials
User Manual: iSPEX 2: Deployment and Operation

Attach iSPEX 2 to any smartphone and gather data on spectropolarimetry by taking a picture of the water, the sky and a grey card for calibration. Since it is attached directly to your phone, iSPEX 2 does not need to enter the water and can be used from the shore or a boat. Data on the intensity and polarisation of light at different wavelengths (colours) is collected and analysed to provide information on the concentrations of certain materials in the water such as: chlorophyll-a, dissolved organic matter, and particulate matter.

Using a smartphone to gather environmental data allows everyone to become a scientist, massively expanding the amount of measurements that can be taken over time and area. As a low-cost sensor iSPEX 2 can easily be used to extend monitoring programmes into remote areas or at any time between official sampling runs.

Through the MONOCLE project the amount and quality of data collected via iSPEX2 has greatly improved through the development of an entirely new hardware design universal to almost every smartphone, and by data analysis now being based on the SPECTACLE method (Burggraaff et al 2019). 

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