Free tool
Drone Photo Coverage Check
Check a mapping flight before you pack up. Drop in the photos, add the field boundary if you have it, and see where every photo was taken, the overlap actually flown, the ALT range, and red boxes wherever data may be missing.
1. Photos from the flight
Only each photo's metadata is read, in this tab. Nothing is uploaded.
2. What you planned
Along each flight line.
Between neighbouring lines.
Field boundary (optional)
Adds a check for any part of the field no photo covers.
Leave blank to use each photo's ALT (height above takeoff). Set it if the takeoff point sat well above or below the field.
Before you leave the field
Catch gaps while you can still re-fly
- Copy the photos from the drone's card to a laptop or tablet and drop the whole folder in.
- Add the boundary you planned from, or draw one with the boundary tool.
- Re-fly the red boxes before processing, so the map or model comes out whole the first time.
Questions
What does the check look at?
Each photo's metadata: GPS position, capture time, ALT, gimbal pitch and heading, camera model, focal length, and image size. The straight-down photos are grouped into flight lines in the order they were taken. The distance between photos along a line gives the front overlap flown, and the distance to the neighbouring line gives the side overlap, both measured against each photo's ground footprint.
What makes a red box?
Three things. Along a line: two photos far enough apart that front overlap falls more than 10 points below your target, or a photo missing from the line's usual spacing. Between lines: side overlap more than 10 points below your target, such as a skipped line. Inside the boundary, if you add one: ground that no straight-down photo covers at all.
Is the altitude ALT or AGL?
ALT: height above the takeoff point, as DJI records it in each photo (RelativeAltitude). Footprints and overlap assume that is the height above the ground being mapped. If you took off well above or below the field, or the field slopes, enter the true height above ground so footprints are sized right.
Which drones and cameras work?
Any camera that writes GPS into its photos. DJI aircraft also record ALT and gimbal angles, which the check uses. The Mavic 3 Enterprise and Multispectral, Matrice 3D and 4 series, Phantom 4 RTK, Zenmuse P1, and the thermal models are recognised by name. Other cameras are sized from their focal length and 35 mm equivalent. Oblique photos are shown on the map but left out of the overlap check.
What should I do about a gap?
Zoom to it and look at the photos either side. A gap along a line usually means a missed trigger or a gust; between lines, a skipped or shortened line. Re-fly that area before leaving the field if you can. Download the gaps as KML to see them in Google Earth or to draw a small re-flight with the KML to FlightHub 2 tool.
Are my photos uploaded?
No. The browser reads only the first 256 KB of each photo, where the metadata sits, and everything stays in this tab. Nothing is sent to AcreWatch or anyone else, and closing the tab discards it.