First in Full Range PDA Spectrometer, Spectroradiometer and Spectrophotometer Systems
1 Canal Street  ◊  Unit B1
Lawrence, MA 01840  USA
Tel: 978 687-1833  ◊  Fax: 978 945-0372

Copyright © 2012 Spectral Evolution, Inc
The PSR+ is designed for field use in vegetation reseaerch. The unit is
lightweight and portable with two Li-ion batteries for a full day in the field, and no
moving optical parts to breakdown. High resolution and unmatched sensitivity
(NER specifications) make the PSR+ the spectroradiometer of choice for critical
field work, including measuring water content in leaves with our leaf clip and
ILM-105 light source.
To accurately estimate vegetation health, it's important to
measure water content. Water stress negatively affects plant
growth and health, cutting back on photosynthesis efficiency. In
most cases, researchers look at water content on a leaf/variety

A portable field agricultural spectrometer like the
PSR+ allows
researchers to measure water content/stress in the field without
affecting the sample. The PSR+ is a full range (350-2500nm) NIR
field portable spectroradiometer with high resolution and high
sensitivity for clear and accurate spectra. Using the PSR+,
spectra are collected quickly, accurately and without sample
preparation. The spectra can exhibit main water absorption
features including the most pronounced at 1450nm and 1950nm.
In addition less prominent but easily recognized features
between 400-700nm can also be analyzed.

All data is saved as ASCII files for use with 3rd party analysis
software like R or ENVI. The PSR+ and all Spectral Evolution
spectroradiometers include DARWin SP Data Acquisition
software with 19 vegetation indices, including the Normalized
Difference Water index (NWDI) and Water Band Index (WBI). The
indices areaccessed from pull down  menus in DARWin.

Leaf spectra can be collected using our unique leaf clip which
features a reversible plate with one side for white reference
measurements and the other for leaf reflectance. The leaf clip
includes a light source that is kept away from the sample so no
heat-related problems occur to damage the sample.

Download a technical paper on maize foliar water stress levels
by clicking here.

Click here for more information on our leaf clip and ILM-105 light
DARWin SP Data Acquisition software is included with every spectrometer and
spectroradiometer. DARWin includes a pulldown menu for access to 19
vegetation indices including NDVI, NDWI, and WBI.
Measuring Water Content in Vegetation