Design of low-cost, compact and weather-proof whole sky imagers for high-dynamic-range captures
This work addresses the need for durable sky imaging systems for cloud monitoring in specific climates, representing an incremental improvement over previous models.
The researchers tackled the problem of designing weather-resistant whole sky imagers for hot and humid climates by developing two new models that use high-dynamic-range imaging instead of mechanical sun blockers, resulting in devices capable of operating in Singapore's conditions with regulated internal temperatures.
Ground-based whole sky imagers are popular for monitoring cloud formations, which is necessary for various applications. We present two new Wide Angle High-Resolution Sky Imaging System (WAHRSIS) models, which were designed especially to withstand the hot and humid climate of Singapore. The first uses a fully sealed casing, whose interior temperature is regulated using a Peltier cooler. The second features a double roof design with ventilation grids on the sides, allowing the outside air to flow through the device. Measurements of temperature inside these two devices show their ability to operate in Singapore weather conditions. Unlike our original WAHRSIS model, neither uses a mechanical sun blocker to prevent the direct sunlight from reaching the camera; instead they rely on high-dynamic-range imaging (HDRI) techniques to reduce the glare from the sun.