Processing (orthomosaic, DSM)

Processing is DroneField’s core action: from drone imagery it produces the orthomosaic (a unified, orthorectified RGB image), the DSM (surface model), and — when requested — the multispectral vegetation indices.

Processing runs entirely locally: no cloud, no queue. Your data stays on your machine.

See it in action: 1,782 Phantom 4 Multispectral images processed in 20 seconds on a MacBook M4:

Starting

1. Open a project with imported imagery.
2. In the right-hand Actions section, click Process.
3. The Processing settings panel opens.

The processing settings panel

Three main controls:

Target GSD (resolution)

GSD = Ground Sampling Distance, i.e. how many centimetres on the ground a single pixel represents in the final orthomosaic. DroneField’s supported range:

• Minimum: 3 cm/px
• Maximum: 20 cm/px

Three presets are offered, and any value inside the range is acceptable:

Preset	GSD (cm/px)	Good for
Precision farming	3 – 10	NDVI analysis, detailed inspection
Flight planning	5 – 7	Recommended for drone-applied VRA maps
Quick overview	15 – 20	Quick check, flight-path validation

Recommended values by purpose:

• Drone-applied application map: 5–7 cm/px
• Ground (tractor) application: 10 cm/px
• NDVI analysis: 3–5 cm/px

The smaller the GSD (e.g. 3 cm/px), the:

• More detail in the orthomosaic
• Larger the file size
• Slower the processing (2–4× longer)

The default is 5 cm/px for most farm-scale work.

Process multispectral images

Only meaningful for P4M or M3M. When enabled:

• All vegetation indices (NDVI, GNDVI, NDRE) are produced automatically
• The individual MS bands (G, R, RE, NIR) are orthorectified as separate layers
• Processing time increases roughly 40% (multi-band rendering)

For RGB-only drones this switch is disabled.

Terrain mode

Turn this on for hilly terrain. Then:

• Twice as many tie points between images
• A finer-grained surface-model grid for more accurate terrain
• A more detailed 3D terrain surface (see 3D Map)
• Processing is ~50% slower

On flat terrain (e.g. Hungarian Great Plain), leave it off — it needlessly slows things down.

High resolution (HQ)

Below Terrain mode. When enabled, the source images are processed at a higher resolution, so the orthomosaic stays sharper when you zoom in. Worth switching on when image quality matters — but expect roughly 2× longer processing, more memory (the time estimate reflects it) and, on large fields, a considerably larger output file. HQ projects carry a purple HQ badge in the project list. On machines with less memory the app automatically steps the resolution down instead of stopping.

Two launch options — Start vs Fast processing

Two buttons at the bottom of the panel:

Start (default)

The precise, industrial-quality processing. Use this for the final orthomosaic, NDVI analysis, application map, report — anything where accuracy counts.

Processing time: a 100-image Mavic 3 M RTK RGB survey takes less than 40 seconds on an Intel i9 / 16 GB RAM / Windows machine (6 cm GSD), and less than 30 seconds on a Mac M4 / 24 GB RAM / macOS 26 machine (5 cm GSD); multispectral processing adds roughly 40-60% to the runtime.

Fast processing

Significantly faster, simplified mode — roughly 30 seconds to 2 minutes for 200 images. Use it when:

• On-site you want a quick preview by the drone
• You only care about coverage (is every patch surveyed?)
• Precise alignment isn’t required

The two modes produce the same output structure — you can later rerun in precise mode with the same imagery. Credits or licence aren’t re-charged on rerun; the same project is unlimited.

The processing overlay

After launch, a translucent overlay appears on the map with the phase indicator:

┌────────────────────────────────────────┐
│  ⚙ Position refinement is running…     │
│                                          │
│  ████████████░░░░░░░░░░░░░░░ 62%       │
│                                          │
│  Elapsed: 4 m 12 s · Remaining: ~2 m    │
└────────────────────────────────────────┘

The phases in order:

1. Image analysis — reading image metadata
2. Tie-point search — finding matching points between image pairs
3. Position refinement — pixel-precise optimisation
4. Surface model — building the terrain grid
5. Render preparation — assembling the texture mosaic
6. Orthomosaic render — the final orthorectified image
7. Vegetation indices (if requested) — NDVI, GNDVI, NDRE
8. Done — saving outputs

The Cancel button stops processing at the end of the current phase — partial results remain, but later phases don’t run.

Tips for best results

• Keep the Mac cool — long jobs (15+ minutes) can throttle the M3 thermally. An open desk, cool surface, and a stand all help.
• Close other applications — particularly memory-hungry Adobe apps.
• Use NVMe SSDs — faster intermediate writes save lots of time.
• 24+ GB RAM is recommended for 500+ image projects.
• Watch memory usage on the Settings → Diagnostics panel while processing.

What do you get at the end?

The map automatically shows the fresh layers:

• Orthomosaic — RGB orthorectified image
• DSM — surface model (greyscale + contours)
• NDVI / GNDVI / NDRE (if requested)
• Flight path (green line)

The right-hand Project info panel gets fresh figures:

• Average GSD (precise value from processing)
• Accuracy — based on RTK statistics
• Area — precise hectare value

Reprocessing

The Process button can be hit again on the same project:

• New settings (different GSD, different mode) overwrite the old results
• Credits are not consumed again — a project licence is spent once, then unlimited reruns

The intermediate files folder

Processing writes intermediate files into the project’s Layers/ folder — e.g. 3D terrain data, tie-point cache, texture cache. These are safe to delete afterwards to reclaim space — the final outputs (Export/ folder) are kept separately.

Settings → Maintenance clears these across every project with one button.