SunScan
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Delta-T Devices Portable canopy analysis system for crops SunScan uses field measurements of PAR in crop canopies to provide valuable information about Leaf Area Index and biomass production.    Measures incident and transmitted PAR in plant canopies Usable in cloudy, clear and changeable conditions Direct display of Leaf Area Index (LAI) Unique BF5 Sunshine Sensor reference measures Direct and Diffuse components of incident light Portable, weatherproof and battery powered Introduction SunScan is a simple and flexible system for measuring and analysing the incident and transmitted Photosynthetically Active Radiation (PAR) within crop canopies. It provides vital information about the penetration of PAR into crops, and is essential in work SunScan Probe such as comparative crop studies, for separating out the The probe has an array of 64 PAR effects of cultivar and treatment. It is particularly well sensors embedded in a 1m long probe, and is suited to low regular canopies (as found in many connected via an RS-232 cable to a handheld PDA. agricultural crops). As a reading is taken, all the sensors are scanned and SunScan users don't have to wait for the measurements are transmitted to the PDA. special weather conditions – the The average light level along the probe is calculated, and all of the probe can be used in most individual sensor readings are available if required for detailed PAR light conditions (but best mapping. An operating button on the probe handle enables successive near mid-day). readings to be taken quickly and simply on demand. Alternatively, unattended logging can be conducted under program control from the PDA. Readings are in units of PAR quantum flux (mol.m-2.s-1) and units of LAI (m2.m-2). Main SunScan components an

SunData software modelling SunScan uses a sophisticated model of light transmission through a uniform canopy, based on work by Campbell (1985), and Norman and Jarvis (1975) and taking into account the following factors: • Direct & Diffuse incident light • Canopy Leaf Area Index • Leaf PAR absorption • Solar zenith angle • Canopy Leaf Angle Distribution • Transmitted fraction Solar zenith angle is calculated from the actual time, latitude and longitude. Leaf Angle Distribution and Leaf Absorption are estimated by the user. All other variables necessary to calculate LAI are measured...

Ordering information SunScan systems All systems are based on the main components listed below. SunScan Complete System type SS1-COM SunScan Probe, SDA2 SunData Software, RPDA2, Sunshine Sensor type BF5 with cables type BF5-SS1-05 and EXT/8W-05, Tripod and Carrying Case. SunScan Complete System with Radio Link type SS1-COM-R4 as above with BF5-RL4 and SS1-RL4. SunScan Standard System type SS1-STD3 SunScan Probe, SDA2 SunData Software and RPDA2. Main components SunScan Probe type SS1 including alkaline batteries and user manual (technical manual on CD). SunScan Probe with radio link type...