CraigTopo

on Exporting to Civil3D - best workflow?

Few tips that sped up my workflow: 1. Export classified point cloud from DroneDeploy, not raw. The classification is decent and saves time. 2. Use the "Ground" class only for your surface. Don't import everything. 3. Thin the point cloud before surface creation. You don't need 50 points per square foot for a topo surface. I thin to 1 point per 0.5-1ft depending on the site. 4. Build surface from point cloud not from points. Civil3D handles point clouds more efficiently now. 5. Generate contours from surface, not from points. With this workflow a 50 acre site goes from DroneDeploy to finished contours in maybe 30 minutes for me.

on Exporting contours from drone data - what interval and format?

Export the DTM as a TIN surface to Civil3D, then generate contours there. You get much better control over smoothing and you can classify/edit the surface before contouring. Never deliver raw photogrammetric contours - they always look bad. A little surface cleanup goes a long way.

on Coordinate system headaches - NAD83 vs WGS84 vs local

DroneDeploy has gotten better at this. You can set your output coordinate system in the project settings now. Still not perfect but saves a step. For local assumed systems though, you're stuck doing manual transformations. No way around it.

on Ground control targets - what brand/size are you using?

Hot take: spray paint on the ground works fine for construction sites. Quick, visible, disposable. Just mark your points and move on. We use inverted marking paint in an X pattern.

on Stockpile monitoring dashboard we built in-house

Are you using the DroneDeploy API for this? Been wanting to do something similar but their API documentation is sparse.

on Coordinate systems in DroneDeploy - how do you handle state plane?

You can set the coordinate system directly in DroneDeploy before processing. Go to Map Settings > Coordinate System and search for your EPSG code. California Zone 5 is EPSG:2229 (feet) or 26945 (meters). If you set it before processing, everything comes out in that system. No need to transform in Civil3D. Also make sure your GCPs are in the same system or it'll be a mess.

on Oblique imagery for facade surveys - flight planning tips

Don't forget a nadir pass too. The combination of nadir + oblique gives much better results than oblique alone. I usually do one nadir grid, then four oblique passes (N/S/E/W facing).

on Cross-sections from drone data - workflow tips?

Civil3D corridors are actually great for this once you set up the templates. Create your alignment, attach the drone surface, and use the section editor. You can batch export to XML for reporting. The trick is setting up your templates right the first time.

on OpenDroneMap vs paid alternatives - honest comparison?

I ran the same dataset through WebODM and Pix4D last month. Results were surprisingly close - within 2cm on checkpoints. WebODM took about 40% longer to process though. The real difference is workflow and export options. Pix4D just has more polish and better Civil3D integration.

on DroneDeploy vs Pix4D vs Propeller - which one for a surveyor?

Interesting. Sounds like DroneDeploy might be the move for variety. Anyone know how the Civil3D export works? That's where most of my deliverables end up.