Veteran aerial photographers can roll out their trusty old Cessna 177 as leading precision ag mappers are dumping drone and satellite shots in favour of higher quality images from genuine piloted aircraft.
The 177 has long been a favourite of aerial photographers. There’s no wing struts to get in the way of a good shot, doors are easily removed, many have been fitted with belly hatches for vertical photography, and later model 177RG planes have retractable landing gear. Cessna says they built 4,295 units between 1968 and 1978.
In the years since, Cessna 177 numbers have not significantly declined. Here’s why — contrary to the popular myth, experienced aerial photographers and their aircraft are in greater demand as clients ask for the best possible resolution, says John Bourne of Ceres Imaging in Oakland, California.
Ceres has a larger market share in California than all the other imaging companies combined, including satellite, drone and aircraft outfits. The ag imaging company serves American farm clients living from the Mississippi River west to the Pacific coast. In some areas, Ceres has enough farmers signed up to contract with aircraft to fly entire regions as one large block of land. Bourne says there’s no way that can be accomplished with UAV, also known as drones.
Satellite and UAV aerial imagery have not turned out to be all they were cracked up to be. Bourne says his company has abandoned UAV imagery. In a phone interview, Bourne says that since dropping drones, Ceres has been able to offer clients the highest accuracy available in the aerial imagery market.
“Farmers and other industries tell us they require high resolution. That’s why we now employ fixed-wing aircraft with pilots. Fixed-wing aircraft give us 20 centimetre resolution, and sometimes as much as 10 cm resolution,” says Bourne.
He adds that each pilot can shoot thousands of acres per day. Once he’s shot a set of fields, he simply flies over to the next set of fields. There’s no time wasted in packing up the drone, driving an hour or more to the next site and setting it up again. Ceres hires aerial photo services that have compatible equipment and have the same personal drive to create high resolution maps.
“We started as a UAV-based company, but very quickly transitioned to aircraft, incorporating a small amount of satellite data as well. We switched out of UAV because aircraft are actually more cost-effective and less time-consuming than drones. We contract with the pilots and tell them what we need shot each day, and they go shoot it.
“The grower doesn’t need to waste time tinkering with technology or processing images or trying to get his maps to reference correctly. He focuses on managing his farm. Our custom pilots focus on gathering images. And we do the data processing and tell the client what it all means.”
While all their primary images are aerial, Ceres uses some satellites for big-picture analysis. He says they use satellite as a low-cost solution to fill in gaps that may have been missed.
Bourne says image resolution is always important, but there’s a related aspect that many people overlook, that being the accuracy of what the model shows. An example, he often uses would be a drone photo that has high resolution but the algorithms don’t match the situation, so the accuracy is wrong. A high-resolution drone photo that isn’t backed up with good data can indicate that a field is water-stressed when, in fact, the opposite is true. That kind of data inaccuracy creates major problems for farmers.
“Retailers all offer fertigation, either through the centre pivot or your drip system. They’re using our images to help give their customers better service. They’re modifying the zones mid-season based on what our images tell them. Growers are switching from up-front to in-season input applications. We’re seeing more input decisions being pushed later in-season than ever before.”
A farmer making seeding plans studies the zones he has created through years of testing, checking and analysis. What goes into the ground depends to a great extent on those zone maps. And while the boundaries may squirm around a little from year to year depending on conditions, they are basically inscribed in digital. There’s no need to start all over and re-do them from scratch.
“When you plan your seeding, you base it on the zones you’ve been comfortable. But things change through the growing season, based on rain, based on temperature or crop disease. You need to be aware of those changes in making decisions on adding nutrient or applying a growth regulator or fungicide. Highly accurate crop information lets you fine-tune your decisions.”
Kirk Stueve is a remote-sensing scientist at Ceres, and a farmer.
“No matter how good your zones are in springtime, after the growing season begins, things happen,” he says. “Our variable rate application zone tool gives growers the in-season intelligence to revise zones or make new ones based on the realities of what’s happening in their fields at that time.
“The VRA zone tool automatically creates management zones, using proprietary high-resolution aerial imagery-based data layers. The layers include water stress, chlorophyll and thermal data to create management zones based on real-time in-season data. Growers choose from two to 25 zones per block, and then import them into their applicator technology.”