Capturing Orthomosaics

 

 

Unless the site is a large utility-scale solar site (>10MW), or there are airspace restrictions preventing a high-altitude flight, we recommend the pilot captures orthomosaic/ base layer imagery. To capture an orthomosaic / base layer imagery, follow these guidelines.

 

Orthomosaic Imagery Requirements

 

Equipment

Drone: Capture with a multi-copter UAS with gimbal mounted camera. A DJI Phantom 4 Pro is a good drone for this purpose but other drones are acceptable as well.

High-resolution camera: 4000×3000 pixel (12 MP) resolution minimum as provided by, for example, the Phantom 4 or Mavic 2 cameras.

Relative position accuracy:
Horizontal: 1.5 m Vertical: 0.5 m.

Absolute position accuracy:
Horizontal: 5 m Vertical: N/A.

 

Ground Sample Distance

5 ± 1 cm/pixel.

 

Altitude

400 feet (AGL).

 

Image Resolution

4000×3000 pixels or greater.

 

Field of View

50 degrees or greater.

 

Gimbal Pitch

Nadir (straight down) with deviation up to 10 degrees acceptable (to avoid glare).

 

Overlap

70% front overlap (direction of flight) and 70% side overlap.

 

Image Alignment

The horizontal edge of the image aligns with the long edge of the solar rows*
*See special instructions for fixed-wing drones.

 

File Format

JPEG
Metadata must contain GPS location, relative altitude, gimbal pitch, gimbal yaw, gimbal roll and timestamp.

 

Image Quality

Imagery must be free from motion blur.
Imagery must contain minimal glare.

Enviornmental Conditions

Skies are clear and sunny or slightly overcast.

Irradiance greater or equal to 600 Watts per square meter.

*We recommend irradiance meter use to confirm sufficient irradiance.

If requested, pilots will be required to supply Raptor Maps with images proving POA irradiance from a sensor. If pilots cannot prove irradiance was above 600 Watts per square meter throughout the flight, a reflight will be required.

Humidity ideally less than 60%.

Wind below 6.7 m/s (15 MPH).

Sample image captured during mapping flight.