Multispectral Mapping in Ireland
Multispectral mapping uses specialist sensors to capture data across multiple wavelength bands, revealing information about vegetation, soil, and water that is invisible to standard cameras. The technology is widely used in precision agriculture, environmental monitoring, forestry, and habitat assessment, providing the detailed analysis needed to make informed land management decisions.
We provide multispectral drone mapping services across Ireland using the Micasense Altum sensor, which captures five discrete spectral bands plus a thermal band simultaneously. Whether you need crop health analysis for precision farming, habitat classification for an ecological assessment, or canopy condition data for forestry management, we deliver processed vegetation indices and classified maps tailored to your specific requirements.
How We Capture Multispectral Data
Our sensor is the Micasense Altum, mounted on a DJI M300 platform. The Altum captures six images simultaneously across blue (475 nm), green (560 nm), red (668 nm), red edge (717 nm), near-infrared (842 nm), and thermal longwave infrared bands. This combination provides the spectral range needed for accurate vegetation index calculations and thermal analysis.
A downwelling light sensor (DLS) mounted on top of the drone continuously measures ambient light intensity and sun angle across all five spectral bands during each flight. Specialised processing software uses this DLS data to correct for changes in lighting conditions, such as clouds passing over the sun, ensuring consistent and comparable results across a survey and between repeat visits.
Multispectral sensors have a smaller field of view than standard RGB cameras, so missions require lower flight altitudes and higher image overlap. We use UGCS flight planning software with terrain-following enabled, which adjusts the drone’s altitude as the ground rises and falls to maintain a constant ground-sampling distance across undulating terrain. Data volumes are substantial, as each capture generates six images, so we manage processing on-site as needed.
All data is processed using Agisoft Metashape, which handles RGB, multispectral, and thermal imagery in a single workflow. We deliver georeferenced orthomosaics, vegetation index maps, and classified outputs in standard formats including GeoTIFF, shapefile, and KMZ.
Vegetation Indices and Data Processing
Vegetation indices are mathematical formulae applied to specific spectral bands to highlight particular characteristics of vegetation, soil, or water. The most widely used is NDVI (normalised difference vegetation index), which measures the difference between near-infrared reflectance (strongly reflected by healthy vegetation) and red reflectance (absorbed by chlorophyll). The formula is: NDVI = (NIR – Red) / (NIR + Red)
NDVI values range from -1 to +1. Healthy, photosynthetically active vegetation typically scores between 0.6 and 0.9. Bare soil, water, and stressed vegetation return lower values. Beyond NDVI, we can calculate NDRE (normalised difference red edge), which is more sensitive to chlorophyll content in dense canopies, and a range of other indices depending on the analysis required.
It is worth noting that some drone platforms and software packages offer what they describe as NDVI using standard RGB cameras with colour filters applied to the output. This is not genuine multispectral imaging. Without the near-infrared and red edge bands captured by a dedicated multispectral sensor, these outputs lack the spectral data needed for accurate vegetation analysis. We use only genuine multispectral sensors for all index calculations.
Precision Agriculture
Multispectral mapping is essential for precision agriculture. By surveying farmland before any intervention, you can identify exactly where crop stress, nutrient deficiencies, pest damage, or waterlogging occur, allowing you to target treatments precisely rather than applying chemicals and fertiliser uniformly across an entire field.
Our multispectral surveys support variable-rate application (VRA) by providing prescription maps that modern GPS-guided sprayers and spreaders use to automatically adjust application rates. This reduces input costs, limits chemical use to the areas that actually need it, and supports compliance with Department of Agriculture, Food and the Marine (DAFM) guidelines on responsible pesticide and nutrient management.
Typical agricultural applications include identifying pest and disease outbreaks early, detecting nitrogen and nutrient deficiencies, measuring water stress and drainage problems, monitoring crop growth stage and estimating yield, assessing crop damage from weather events or machinery, and supporting agricultural insurance claims with objective evidence.
Environmental Monitoring and Habitat Mapping
Multispectral data is increasingly used in environmental monitoring and ecological assessment in Ireland. Environmental consultants use drone-captured multispectral imagery to classify habitat types, map vegetation communities, detect invasive species, and monitor changes in vegetation condition over time.
For Appropriate Assessments and Natura Impact Statements under the EU Habitats Directive, multispectral surveys provide the habitat extent mapping and vegetation classification evidence that ecologists require. The spectral signatures of different plant communities allow trained analysts to distinguish between habitat types and identify areas of degradation or colonisation by invasive species such as Rhododendron ponticum or Spartina anglica. Water quality indicators, including algal bloom extent and turbidity, can also be assessed using specific band combinations.
Forestry and Woodland Assessment
Multispectral mapping provides forest managers with detailed canopy health data at a resolution that satellite imagery cannot match. NDVI and NDRE indices highlight areas of stress caused by disease, drought, wind damage, or nutrient deficiency across large areas of plantation or native woodland. Repeat surveys at seasonal intervals track changes in canopy condition and recovery after thinning operations.
When combined with LiDAR data, multispectral outputs support species classification, growth-rate analysis, and environmental impact assessments for forestry operations. We deliver outputs compatible with standard GIS platforms for integration into existing forest management systems.
Turf Management and Sports Surfaces
Golf courses, sports pitches, and amenity grasslands benefit from multispectral surveys that map turf health, moisture distribution, and disease pressure across the entire surface. Greenkeepers and turf managers use the resulting maps to target aeration, fertiliser application, and irrigation adjustments to specific areas rather than treating the whole surface uniformly.
For golf courses, multispectral data supports seasonal maintenance planning and provides objective documentation of course condition for club management reporting.
Frequently Asked Questions
Standard RGB cameras capture three visible light bands (red, green, blue). Multispectral sensors capture additional bands beyond visible light, including red edge and near-infrared, which reveal information about plant health, moisture content, and soil conditions that RGB cameras cannot detect. Only genuine multispectral sensors provide the data needed for accurate vegetation index calculations.
Accuracy depends on the sensor quality, calibration, flight conditions, and processing methodology. Our Micasense Altum sensor with downwelling light sensor calibration produces research-grade NDVI and NDRE outputs. The DLS compensates for changing light conditions during the flight, ensuring consistent results. We recommend flying in even lighting conditions where possible for the best results.
Yes. Multispectral outputs are used by environmental consultants to support Appropriate Assessments, Environmental Impact Assessment Reports (EIARs), and habitat condition monitoring under the EU Habitats Directive. The data provides objective, repeatable evidence of vegetation condition and habitat extent.
This depends on the required ground sampling distance, terrain complexity, and airspace restrictions. For a typical agricultural survey flown at 80 metres altitude, we can cover approximately 50 to 80 hectares per day. Larger areas may require multiple survey days. We confirm coverage rates during the initial consultation based on your specific site conditions.
Standard deliverables include georeferenced orthomosaic imagery, NDVI and other requested vegetation index maps, and a summary report. We deliver in GeoTIFF, shapefile, and KMZ formats for compatibility with GIS platforms, precision agriculture software, and standard mapping tools. Additional outputs such as classified vegetation maps or prescription maps for variable rate application can be produced on request.