Learning Center

Get elevation data for contours

Contours are drawn from an elevation surface of the whole field. Load a Saved LiDAR DEM (best, works offline), import a GeoTIFF or a point file, use a whole-field survey you saved, drive the field now, or open LiDAR & Mapping to fetch LiDAR. Which kits can draw contours, and what each source asks you.

  • Full Automation Kit
  • Guidance Only Kit
  • Ditch Assist Lite

In the app Levee › Use Existing Data › How do you want to get started?

A contour is a line of equal elevation, so the app needs elevations across the whole field, not along one line: an elevation surface (a DEM). You only need it once per field. The same sources feed Levee, Contour-Guided Terracing and Contour Tiling.

Before you start

Time: about a minute to load saved data; driving a new field takes as long as the drive.

Who can draw contours

Loading, surveying and exporting work on any connection. Drawing and following contours needs a control module (Full Automation or Guidance Only Kit), an activated Reach (Ditch Assist Lite), or Simulate. On a DIG™ module or a Bluetooth GPS the app stops at Contour guidance is for Ditch Assist owners; an unactivated Reach opens the activation screen instead (Activate).

The sources

On the Levee screen they're the buttons under How do you want to get started?; the sidebar has the same actions with shorter names.

Levee screen with nothing loaded: top bar Generate contours to begin; source panel with Survey New Field, Saved Survey, Point File, GeoTIFF DEM, Saved LiDAR DEM, Open LiDAR & Mapping and Load Saved Job; sidebar Import DEM, LiDAR, Load Survey, Points, Drive to Map, Load Job
  1. Saved LiDAR DEM. The usual choice. The other buttons in the panel are the other sources.
  2. The right-hand column. The same actions with shorter names: Import DEM (GeoTIFF DEM), LiDAR (Saved LiDAR DEM), then Load Survey, Points, Drive to Map and Load Job.
SourceBest forAsks you
Saved LiDAR DEMMost fields in the US and Canada. Prepared once on internet Wi-Fi, then works with no internet.Which field. Comes with its boundary; always in metres.
GeoTIFF DEMA drone or survey-software elevation raster (.tif).Draw a boundary or not; the file's units (Meters / Feet).
Point FileA text file of lat, lon, elevation points.Columns, delimiter, header row, units.
Saved SurveyA whole-field survey you drove before with Field Survey.Which survey.
Survey New FieldNo data yet and a field you can drive.A benchmark first, then you drive.
Open LiDAR & MappingFetching LiDAR now, when you have internet.Sends you to LiDAR & Mapping.

Saved LiDAR DEM

Tap Saved LiDAR DEM

It's the fourth button in the row under Or use existing data, in the middle of the screen (or LiDAR in the right-hand column). A list of your saved fields opens.

Levee source panel with the Saved LiDAR DEM button
  1. Saved LiDAR DEM. Tap it.

Tap your field

Each row shows a field saved from LiDAR & Mapping, with its area and detail. Tap yours. Contour Settings opens next, using the field's own boundary.

One row of the saved LiDAR DEM list: a small hills icon, the field name Section 12 West, and under it 251 ac · 2.8 m/px 1
  1. A saved field. Name, acres · metres per pixel.

Empty list: No saved LiDAR DEMs found. Use LiDAR & Mapping while online to save one first. See Prepare a field and Reuse the saved DEM offline.

GeoTIFF DEM

Tap GeoTIFF DEM

It's the third button in the row under Or use existing data (or Import DEM in the right-hand column). The tablet's file picker opens.

Levee source panel with the GeoTIFF DEM button
  1. GeoTIFF DEM. Tap it.

Tap the Download folder

The picker opens on the tablet's folders; the name at the top is your tablet's model. Files you download or copy over usually land in Download. Tap it.

Android file picker showing the tablet's folders: Alarms, Android, Audiobooks, DCIM, Documents, Download, Movies, Music and more
  1. Download. Tap the folder your file is in.

Not on the tablet yet: Move files to the tablet.

Tap the .tif file

A GeoTIFF has a red picture icon and ends in .tif. Tap it. It can be up to 64 MB / 4,000,000 cells. The app reads it, then asks Define field boundary?.

Files in Download: design files and a GeoTIFF named field-dem.tif, 2.36 MB, with a red picture icon
  1. The .tif. Your file's name will differ.

Tap Skip or Draw Boundary

A boundary keeps contours off roads, ditches and the neighbour's ground. Skip (use full extent) on the left uses the whole file; Draw Boundary on the right lets you tap the field corners.

The two buttons at the bottom of the Define field boundary? window: Skip (use full extent) in white and Draw Boundary in green 1 2
  1. Skip (use full extent). Contours over the whole file.
  2. Draw Boundary. Tap the field corners (how).

Tell it the file's units

A GeoTIFF doesn't always say whether its elevations are metres or feet, so Contour Settings shows Source units. It starts on Feet; most LiDAR and drone DEMs are in metres. Pick wrong and the contours come out about three times too far apart (a metre file left on Feet) or too close together (a feet file set to Meters).

The Elev range and Estimated contours lines are always worked out as if the file were in metres, and don't change when you tap Meters or Feet. For a feet file they read about three times high: here a file with about 100 ft of relief shows 328 ft and ~1,312 lines, and the many-contours limit greys out Generate. Pick a larger interval to get under it, then judge the spacing on the map.

Contour Settings for a GeoTIFF, lower part: Source units Meters / Feet with Feet picked, Smoothing at Medium, Estimated contours ~1312 lines in red, Many contours — consider a larger interval., and Generate greyed out 1 3
  1. Source units. Tap Meters or Feet, as the file really is. Feet is picked to start.
  2. Estimated contours. Turns red over 500 lines, with Many contours — consider a larger interval. under it.
  3. Generate. Grey until you pick a larger interval.

File errors: Could not parse GeoTIFF file, GeoTIFF has no valid elevation data, or This DEM is too large to load … (clip it to the field). More: Fix import errors.

Point File

A text file (.txt, .csv, .xyz, .tsv) with latitude, longitude and elevation on each line. At least 10 good points are needed (Too few valid points parsed …). The app fills the gaps between points to make a surface, so even, dense points give the best contours.

Tap Point File

It's the second button in the row under Or use existing data (or Points in the right-hand column). The tablet's file picker opens.

Levee source panel with the Point File button
  1. Point File. Tap it.

Tap your point file

Open the folder it's in (usually Download), then tap the file. Import Point File opens.

Files in Download in the tablet's file picker, including a point file named S1_XYZ_Raw.xyz
  1. A point file. Your file's name will differ.

Check the settings, then tap Import

The top shows the first five lines of the file. Check the Delimiter, Header row and the three column boxes match what you see there. Elevation in starts on Feet: tap Meters for a metre file. Then tap Import at the bottom right.

Import Point File: Preview (first 5 lines) of latitude longitude elevation rows (blurred here), Delimiter Whitespace (space/tab), Header row checkbox, Lat column Col 1, Lon column Col 2, Elev column Col 3, Elevation in Meters / Feet, Cancel and Import 1 2 3
  1. Preview. Check it's lat, lon, elevation.
  2. Delimiter. Whitespace, comma, tab, semicolon or single space.
  3. Columns. Which column is Lat, Lon, Elev.
  4. Elevation in. Starts on Feet: change it for a metre file.
  5. Import. Builds the surface; Contour Settings opens next.

Saved Survey

Tap Saved Survey

It's the first button in the row under Or use existing data (or Load Survey in the right-hand column). Load Saved Survey opens with your whole-field surveys from Field Survey, each with its points, sessions and date.

Levee source panel with the Saved Survey button
  1. Saved Survey. Tap it.

Tap Use for Contours

It's the wide button under the survey's name. The app builds the surface (Generating elevation surface…), then Contour Settings opens. The icons on the right of the row export / share the survey (Export from Levee) or delete it; the bin deletes at once, with no confirmation.

Load Saved Survey: North 40 levee, 59 points • 1 session(s) • date, Export / share and Delete icons, Use for Contours, Cancel 2
  1. Use for Contours. Builds the surface from this survey.
  2. Export / share, Delete. The bin deletes straight away.

Only whole-field surveys are listed, not ditch or channel line surveys. Nothing saved: No saved surveys found. Survey a field first. Fewer than 10 points: Survey has fewer than 10 points; not enough to interpolate.

Survey New Field

Survey New Field (in the Levee wizard, the source panel, or sidebar Drive to Map) opens Field Survey. Drop a benchmark, drive the field back and forth about a swath apart, tap Finish & Save, then Save & Use Now to go straight on to the contours. Step by step: Survey a whole field.

Open LiDAR & Mapping

Open LiDAR & Mapping (sidebar LiDAR) switches to LiDAR & Mapping to draw a boundary and fetch public LiDAR: Draw and save a LiDAR DEM, then reconnect to the controller and load it from Saved LiDAR DEM. It needs internet, which the control module's Wi-Fi doesn't have, so do it before you go out. It also needs the one-time unlock; until then it shows LiDAR & Mapping is for Ditch Assist owners.

LiDAR & Mapping is for Ditch Assist owners, with one-time activation steps: join the control module Wi-Fi with password 12345678, tap a workflow card and Connect, switch back to normal internet; OK
  1. OK. Closes the window. Do the three steps below once, then LiDAR works on any internet.
  1. Join the control module's Wi-Fi (password 12345678) in the tablet's Wi-Fi settings (how).
  2. Come back to Ditch Assist, tap any workflow card, then tap Connect.
  3. Switch the tablet back to your normal internet (farm Wi-Fi or phone hotspot).

A DIG module or an activated Reach also unlocks it. Full steps: Unlock it once.

LiDAR & Mapping, start to finish Five steps. While the tablet has internet: 1, draw the field boundary on the map, up to 800 acres; 2, the app fetches public LiDAR elevation data, USGS 3DEP in the US or NRCan HRDEM where it covers Canada. No internet needed from here: 3, the tablet itself works out flow lines, depressions and ponding and saves them with the field; 4, the Drainage Planner turns the flow lines into a drainage plan you save; 5, in the field on the control module Wi-Fi, add the layers from Map Layers, and Levee, Contour Tiling and Contour-Guided Terracing use the saved LiDAR DEM. LiDAR & Mapping Needs internet Draw the field Up to 800 acres 1 Fetch LiDAR Public elevation data 2 No internet needed Tablet maps the water Flow, low spots, ponding 3 Plan drains Drainage Planner 4 Use it in the field Layers and saved DEM 5

Prepare each field on internet Wi-Fi. In the field, on the module's Wi-Fi, Levee loads it from Saved LiDAR DEM with no internet.

  1. Draw the field. Tap its corners on the map, up to 800 acres. Steps 1 and 2 need internet: farm Wi-Fi or a phone hotspot, not the control module.
  2. Fetch LiDAR. Public elevation data: USGS 3DEP in the lower 48 states, NRCan HRDEM where it covers Canada.
  3. Tablet maps the water. Flow lines, depressions and ponding are worked out on the tablet and saved with the field. Nothing is sent away.
  4. Plan drains. The Drainage Planner turns the flow lines into a plan you save.
  5. Use it in the field. No internet needed. Add the layers from Map Layers, again after each app restart. Levee, Contour Tiling and Contour-Guided Terracing load the saved LiDAR DEM.

If something goes wrong

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