3 Aerial Image Types You Should Collect

3 Aerial Image Types You Should Collect

By collecting field imagery – whether through a satellite, airplane or even drone – farmers can turn data points into decision points. But an image is never just an image. Often, investigating different types of images can lead to even greater insights, according to Dave Swain, manager of precision ag technologies at Southern States Cooperative.

Southern States studied airplane aerial imagery from 4,000 customer acres this past season, Swain says. In particular, they looked at three distinct types of field images, he says.

1. Aerial view. This is a standard Red, Green, Blue (RGB) image; in other words, a “real-time aerial photo.”

2. Near infra-red (NIR). This images shows the heat and reflectiveness of vegetation in the field. Brighter red areas typically indicate more vegetation. This can sometimes signal high weed pressure, not better crop production.

3. Multi-spectral, or normalized difference vegetative index (NDVI). This image is a combination of RGB and NIR images.  This type of image shows a field’s vegetative vigor or potential health of the crop.

The goal of collecting multiple image types is to ID the potential limiting factors that are limiting maximum crop yields, Swain says.

“Typical limiting factors that may be identified [from these images] are moisture, nutrients or compaction,” he says. “Most farmers know where the good and bad producing areas are in their fields. We aren’t really telling them something they don’t already know.”

Southern States used airplanes to capture aerial imagery for its customers. Swain says that allowed them to capture images at one meter, one-half meter or one-quarter meter resolution, comparable to what can be collected with UAVs and higher than what is typically captured via satellite (5-meter resolution).

For the “DIY” crowd who prefer their own drone and capture their own multispectral imagery, there are a wealth of YouTube videos such as this one that describe how to convert a regular camera so it can take NIR or NDVI imagery.

Have a question about RGB, NIR or NDVI imagery? Ask for answers on the AgWeb technology discussion boards.

Back to news


Spell Check

Texas Hoosier
Fort Worth, UM
3/25/2015 05:26 AM

  The resolution numbers for commercial satellite imagery, specifically panchromatic and multi-spectral images from WorldView-1, WorldView-2, Worldview-3, GeoEye-1, QuickBird-2, and Ikonos-2 are as follows: WorldView-1 (Pan Only - 19.68 inches); WorldView-2 (Pan - 17.32 inches, MSI - 69.29 inches); WorldView-3 (Pan - 12.20 inches, MSI - 48.8 inches); QuickBird-2 (Pan -25.19 inches, MSI - 100.79 inches); GeoEye-1 (Pan - 16.14 inches, MSI - 64.57 inches); Ikonos (Pan - 31.89 inches, MSI - 127.56 inches). Now, while these values may reflect the maximum resolution capability of the Panchromatic (Black & White) and Multi-Spectral (Color) image producing capabilities of the associated satellite imaging sensor systems, for commercial release of imagery, Panchromatic and Multi-Spectral images are limited to 50 centimeter or 19.69 inch resolution for public release due to US government policy. The quoted value of "5 meter resolution" in this article, which I assume is for panchromatic images has long since been exceeded and would be indicative of the maximum resolution of imagery from the French-built, SPOT-series of satellites that was available starting in 1986, although 5-Meter resolution SPOT images were not available until the launch of SPOT-5 in 2002.


Corn College TV Education Series


Get nearly 8 hours of educational video with Farm Journal's top agronomists. Produced in the field and neatly organized by topic, from spring prep to post-harvest. Order now!


Market Data provided by QTInfo.com
Brought to you by Beyer