The initial analysis of satellite imagery within Cropwise Imagery begins with the Map View. Within the Map View selected images can be displayed according to the selected vegetation index and color palette.
Table of Contents
• Viewing and Filtering Images
• Vegetation Index Descriptions
• Color Palette Adjustment
Viewing and Filtering Images
To begin viewing field satellite imagery in Cropwise Imagery, navigate to Map View within the left-side menu.
Next, select the image catalog dropdown to view the list of available images. Cropwise Imagery defaults to Sentinel, 10 meter resolution images which are available for selection every 3 to 5 days on average. Each available image will display one of three cloud presence icons:
Sunny: low cloud presence
Partially cloudy: medium cloud presence
Cloudy: high cloud presence
Highlighting your cursor next to each available image will indicate the cloud presence level. Images can be filtered based on date selection, cloud presence and sources.
Vegetation Index Descriptions
Cropwise Imagery defaults to the NDVI (Red) vegetation index and can be changed to one of the following options depending on current crop growth stage and agronomic scenarios.
Vegetation Index Description
|The Normalized Difference Vegetation Index (Red) (NDVI (Red)) is the most common index used to measure plant health. The amount of light that is absorbed by the plant is measured from -1 to +1. Non-vegetative objects like roads are calculated in the -1 to 0 range while vegetation is seen in the 0 to +1 range, with 0 being unhealthy and +1 being very healthy.|
|SAVI||The Soil Adjusted Vegetation Index (SAVI) takes into account bare soil alongside the plant that also reflects light. This index is a good choice for early vegetative stage plants or crops that often have bare soil present.|
|Visual||Visual, also known as RGB, is what we would see as humans looking down from space. You can use this view when you want to check for clouds or other atmospheric anomalies on your images.|
The Enhanced Vegetation Index (EVI) filters out some atmospheric inconsistency that NDVI does not. EVI is a good choice when in an area with very dense canopy vegetation.
|NDWI||The Normalized Difference Water Index (NDWI) measures moisture and is great for detecting pools of water in the field. These pools of water show up on the map as red areas.|
|NDVI (Green)||The Normalized Difference Vegetation Index (Green) (NDVI (Green)) is similar to NDVI (Red), but is better suited for later stage plants.|
|The Ratio Vegetation Index (RVI) measures the ratio of NIR to Green. This is often very sensitive to grasses and is a basis for the Cropwise Imagery pasture management system.|
|ARVI||The Atmospherically Resistant Vegetation Index (ARVI) is useful for areas with significant rain, fog, or pollution. The ARVI index is not as sensitive to atmospheric conditions as other indices such as NDVI.|
|NIR||The Near-Infrared (NIR) is the infrared color of the image collected by the satellite. This band of light is used within the calculations of many other indices.|
|VARI||The Visible Atmospherically Resistant Index (VARI) is less sensitive to many atmospheric effects, allowing for vegetation to be estimated in a wide variety of environments|
The legend visible in the Map Controls menu is measured from 0 (red) to 1 (green). A vegetation index is used to measure plant health by calculating how much light the plant is absorbing and using for growth. Areas within fields represented from a light green to solid green, index values closer to 1, will indicate a healthy plant biomass.
A plant reflecting more light is a less healthy plant because it is using less light and will be represented with an index value closer to 0. These areas in the field will be typically represented from yellow to red.
Color Palette Adjustment
The color palette can also be adjusted to other predefined palettes.
Click here to learn about Variability View for a better understanding of the variances within a field.
Click here to learn how to use the Visual slider bar to identify hotspots in imagery.
Click here to learn how to perform a side-by-side image comparison.
Click here to learn about additional mapping tools.
If you have any questions regarding this content, please reach out to us with the contact information provided below.
Syngenta Digital Support
Phone: (270) 435-4369 - Option 1
M-TH: 7:00 AM - 6:00 PM CST
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