AeroCartwright
A reference collection on drone mapping, photogrammetry, LiDAR workflows, and geospatial data processing. Written by a GIS scientist with M.S. GIS, FAA Part 107, and 10+ years of field experience.
In Progress
Each series is a structured body of work on a single subject — published in order, with future articles already scoped. Pick a thread and read it through, or jump in at whatever index matches your skill level.
Series
Aviation checklist methodology applied to drone mapping — the discipline that keeps real survey work defensible. Seven phases from mission planning through deliverable handoff.
Mostly published. Final phase publishing soon.
Six-phase drone mapping checklist from pre-flight to deliverable handoff. Based on aviation protocols — prevents costly reflys and data rejection.
Pre-flight checklist for drone surveys: airspace verification, weather assessment, equipment inspection. Part 1 of the 7-phase drone mapping checklist series.
Altitude, GSD, overlap, battery budget — the four parameters that decide whether drone mapping data is usable. Mission planning checklist for surveyors.
GCP deployment checklist: placement, measurement procedure, photo documentation, field logging. Every step from planning through pre-flight.
Post-flight QA checklist: image review, coverage verification, metadata validation, 3-2-1 backup. Part 4 of the drone mapping checklist series.
Drone processing checklist: CRS setup, alignment QA, GCP integration, checkpoint validation, quality report review. Prevents accuracy failures.
Drone mapping deliverable handoff: file formats, CRS documentation, accuracy statements, client communication. Part 6 of the checklist series.
Series
Mini-4-Pro–class mapping for budget-constrained professionals, freelancers, and serious hobbyists. From first orthomosaic through running a paid practice.
Publishing weekly. New articles every Tue / Thu.
FAA regulates the flight, states regulate the data. Learn where drone mapping crosses into surveying law, which states enforce, and the safe business model.
Fly a grid mission with a consumer drone, process a georeferenced orthomosaic in WebODM within 90 minutes. No GCPs, no survey gear, no paid software.
DJI Mini 4 Pro mapping accuracy: ±6-16 ft GPS-only, ±4-12 in with DIY GCPs, ±0.5-1.2 in with surveyed GCPs. Consumer vs enterprise drones.
Set up survey-accurate GCPs without a surveyor or RTK. DIY target construction, budget measurement equipment, and field procedures that work.
Drone mapping flight parameters: GSD, overlap, altitude, speed. 80% frontal / 70% side minimums. Accuracy improves 11x from 60% to 80% overlap.
WaypointMap vs Litchi Pilot vs DroneLink vs DJI Fly for automated Mini 4 Pro missions. KMZ workflow for RC 2, MSDK apps for Android.
Free WebODM vs paid Pix4D for consumer drone imagery: orthomosaic quality, accuracy, real cost math, and exactly when each one is worth it in 2026.
Series
Deploy WebODM / OpenDroneMap on AWS spot instances. Cloud-scale photogrammetry at single-digit dollar cost per project, with the security and recovery practices that make it production-grade.
Rolling out Jul–Aug 2026.
Confused by OpenDroneMap, WebODM, NodeODM and ClusterODM? Here's what each piece does, which you actually need, and how the free stack compares to Pix4D.
Your first AWS bill says $47.23 when you expected $2. What happened, why egress dominates, and three simple practices to prevent bill shock.
Evergreen
Standalone articles outside the named series — the reference material you reach for when you need to look one specific thing up.
How accurate the survey actually is — RMSE, ground control, checkpoints, RTK and PPK, coordinate systems.
How many ground control points does a drone survey need? 5 GCPs for under 5 acres, 8–12 for 50–500. Distribution beats density — and always include independent checkpoints.
RTK alone produces 2–5 cm horizontal but 5–15 cm vertical bias. Why GCPs still matter, when checkpoint-only works, and the bowling/doming failure mode.
The White House's August 13 Section 232 proclamation puts 25-100% tariffs on imported drones and components, effective Sept. 3. Here's what's confirmed, what isn't, and how it plausibly hits mapping hardware.
Build georeferenced NeRFs from drone imagery: RTK/PPK integration, COLMAP geo-registration, Nerfstudio, point cloud export, checkpoint validation.
Your drone map is a meter low everywhere except around the GCPs. Here is the diagnostic decision tree for vertical bias — and the fixes that actually work.
RMSE drone mapping explained: what the formula means, why vertical is always worse, CE90/LE90 conversions, NSSDA statements, when it's good enough.
The drone map doming effect causes systematic elevation errors up to several feet — and the orthomosaic looks fine. Here's how to detect, fix, and prevent it.
The drone mapping quality report looks reassuring — until a client finds 8-inch errors. Learn to read every Pix4D and Metashape number before delivery.
GCP residuals measure fit, not accuracy. Drone survey checkpoints provide independent validation. How to set them up in Pix4D, Metashape, WebODM.
BVLOS is coming. Part 108 rules, waiver process, equipment, PPK workflows, and the crew-savings math for corridor and linear infrastructure.
Consumer drone mapping buyer's guide: DJI Mini 4 Pro vs Mini 3 Pro vs Autel Evo Nano+. Accuracy, rolling shutter, GCP needs — field-tested verdicts.
WGS84 vs NAD83, state plane, vertical datums — the CRS settings drone operators get wrong, and how to fix them in Metashape, Pix4D, and ODM.
LiDAR vs photogrammetry for drone surveys: real accuracy numbers, hardware costs, processing workflows, and a decision framework — when each technology wins, and when it doesn't.
Four positioning tiers for drone surveys: GPS, RTK/PPK, GCPs, and full RTK+GCPs+checkpoints. Match accuracy to the job — not every project needs the top tier.
RealityCapture vs Agisoft Metashape vs Pix4D vs WebODM — pricing, speed, accuracy, and GCP workflow compared, and which one wins for survey-grade work in 2026.
Real drone survey accuracy in 2026: ±2–5 cm horizontal, ±3–12 cm vertical typical. RMSE vs CE90 vs LE90 explained, ASPRS classes, 5 red flags in any quality report.
RTK vs PPK for drone surveys: both hit 1-3cm accuracy. RTK corrects in real time, PPK processes post-flight. Failure modes, costs, when to use each.
Image-to-model pipelines — overlap, doming, settings, software comparisons, processing settings.
WebODM split from the OpenDroneMap nonprofit on April 6, 2026. What changed, why, and migration steps — new GitHub URLs, Docker images, docs.
PIX4Dmatic 2.0 absorbs PIX4Dsurvey into three tiers. Full comparison vs Metashape and DJI Terra on price, accuracy, GCP workflows, and deliverables.
Compare AI point cloud processing tools: Pix4D, Metashape, OpenPointClass. Real accuracy benchmarks, workflows, and which saves time in practice.
Part 107 authorizes you to fly. It does not authorize you to survey. Where the line is, how states draw it, and how to operate legally in the gray zone.
WebODM 3.2.8 adds DXF export for permanent overlays. OpenDroneMap's ODM 3.6.2 fixes a bug that could silently drop GPS telemetry. Two forks, one week — what shipped.
How to pull the bare earth out of a 50-million-point drone photogrammetry cloud. The three tools compared: algorithm, workflow, cost, failure modes, and which one to pick.
Every ODM processing parameter explained: feature-quality, pc-quality, matcher-type, mesh-size, SMRF, orthophoto-resolution. Three usable presets.
WebODM install guide for Windows, Mac, Linux: Docker setup, first task, hardware requirements, common errors. Free photogrammetry on your hardware.
Classify drone point clouds into ground/vegetation/buildings with Metashape, LAStools, PDAL, CloudCompare, ArcGIS Pro. Tool decision framework.
A practitioner's guide to Agisoft Metashape processing settings: what each quality slider controls, why the tradeoffs matter, and three presets for real jobs.
Image overlap drone mapping: 75/60 is the floor, not the target. Here's what fails when overlap is wrong and how to set photogrammetry overlap by job type.
In April 2026 WebODM forked the OpenDroneMap stack and renamed it — ODM became ODX, NodeODM became NodeODX. Which one you actually install, and why.
Orthomosaic export settings, point cloud formats, DEMs, coordinate systems — and how to package drone deliverables so clients can actually use them.
Compare RealityScan, OpenDroneMap, Meshroom, and COLMAP for photogrammetry on Linux. Headless processing, Docker deployment, and which tool fits your workflow.
Drone data in ArcGIS Pro: import orthomosaics, point clouds, DSMs. Workflow to volume calculations, contours, and ArcGIS Online delivery.
3D Gaussian Splatting for drone operators: vs photogrammetry, accuracy benchmarks, software and pricing, hybrid workflow, what it cannot do.
Digital twin construction contracts pay $3K-15K/month recurring. The three-tier service model, CRS alignment, platforms, and how to win your first.
WebODM cloud vs local: AWS spot costs ($3-5/job), egress surprises, decision framework for when cloud wins vs when your workstation is better.
NeRF vs photogrammetry for drone mapping: accuracy numbers, output products, georeferencing limits, and a decision framework for when each wins.
Complete QGIS workflow for drone data: import orthomosaics, build pyramids, contours from DEMs, point clouds, QField field review. QGIS 3.44 LTR.
An orthomosaic is a georeferenced image mosaic built from overlapping drone photos. How photogrammetry creates one, GSD, GeoTIFF vs COG, GIS use.
DSM vs DTM vs DEM for drone operators: definitions, how each is derived from photogrammetry, ground classification, and when each product is required.
Drone mapping hardware guide: CPU, GPU, RAM, NVMe requirements for photogrammetry. Workstation builds by project size and processing software.
Drone data explained: imagery, orthomosaics, point clouds, elevation models, 3D meshes. How photogrammetry turns photos into geospatial products.
AeroCartwright: drone mapping education and geospatial tools from a working GIS professional with firefighting, academic, and federal field experience.
When LiDAR beats photogrammetry and when it does not. Multispectral, NeRF, Gaussian splatting alternatives.
The FCC's Covered List redefinition proposal names consumer DJI models and a Sept. 2 comment deadline. Here's what's confirmed, what's my analysis, and how to file a comment before the window closes.
Multispectral drones aren't just for crops. Water quality, wildfire, building inspection, mining, forestry — 7 non-ag applications with ROI.
In the field — planning, automation, risk, BVLOS, and what separates professional flight from hobbyist.
Drone mapping risk framework: regulations, crashes, airspace, privacy, GPS spoofing. Four categories with LAANC, insurance, ADS-B, and checklists.
Your Part 107 certificate puts you in the same FAA system as airline captains. Sectional charts, LAANC, ADS-B In — airspace discipline matters.
Part 107, BVLOS waivers, surveying legality, pricing, packaging, and the business of drone mapping.
United Flight 1980 reported striking a red drone on approach to San Diego International Airport. Here's what the incident reveals about mixed airspace risk and what every Part 107 operator needs to understand.
Tools
Free, embeddable, vendor-neutral. Use during mission planning or to sanity-check a deliverable.
Pillar Guide
30+ pages condensing the entire pipeline — mission planning, field ops, processing, deliverables, QA/QC — into a single field-ready PDF. Free.
Free download: The Complete Drone Mapping Workflow Guide — 30+ pages of field-tested methodology.
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