How to Plan a 2D Photogrammetry Mission with the Mavic 3 Enterprise and Matrice 4 Enterprise
The most common type of mission flown with the DJI Mavic 3 Enterprise (M3E) and DJI Matrice 4 Enterprise (M4E) is for 2D photogrammetry. This article provides an overview of this mission planning process.
1. Power on your drone and remote controller (RC).
2. Connect your RC to a WiFi network or hotspot to ensure base maps will load to assist with mission planning. To connect to wifi, pull down from the top of the screen and tap the wifi icon.
3. From the home screen of DJI Pilot, tap Flight Route.
4. Tap the + sign in the top right and select Create a Route
5. Tap Area Route.
6. Locate your site by panning around the map and using two fingers to adjust the zoom.
7. Tap the screen to begin drawing your mission area.
8. Edit the polygon to fit your desired survey area. When you are done editing your polygon, tap the blue check mark.
9. Adjust the mission name and the settings listed in the table below by navigating through several menus in the app. When you encounter settings in the app not mentioned in this table, leave them at their default.
Drone Setting
Set to
Question to Ask Yourself
Reason
Drone / Camera
M3E Series M3E Wide
M4E Series M4E Wide
Which camera are you planning on using for this mission?
The mission parameters will be different for different lenses, so make sure this is set accurately.
Collection Type
Ortho Collection
Do I need vertical faces captured in my model?
Select Ortho Collection if you do not need vertical faces to be captured in high detail. This will ensure your mission is as efficient as possible while collecting enough imagery to build an accurate 3D model.
Ortho GSD
Default
Do I need to achieve a specific ground sample distance for this flight?
View the GSD estimate to understand what resolution to expect with the current settings. Remember that manually increasing or decreasing the Ortho GSD value will alter other mission settings, such as flight route altitude.
ASL/ALT
Relative to Takeoff Point (ALT)
What elevation is your target altitude referenced to?
Unless you are referencing to altitude above Sea Level (ASL) in the EGM96 geoid model, set this to ALT.
Route Altitude
200-400ft (60-120m)
How high should I fly compared to the takeoff point?
The height is a balance between how quickly you would like to complete your survey (higher makes it faster) and the ground sampling distance that you need. This range satisfies this balance.
Elevation Optimization
Disabled
Is my terrain or altitude expected to vary during flight?
When enabled, the drone will take a few oblique images at the end of the flight. You do not need these to process your data with Propeller.
Safe Takeoff Altitude
User Preference
Are there obstacles in my takeoff area?
Set the Safe Takeoff Altitude to be higher than the tallest obstacle in your area. This will ensure the drone flies straight up until it is above the obstacles before traveling to your mission start point.
Speed
Max Speed Allowable*
How fast should I fly?
*Unless you're trying to reach the required 10 minute mission time, increase the speed to minimize overall flight time. In low light conditions, reduce the speed and the shutter speed to ~1/800.
Course Angle
User Preference
What direction should I fly to cover the survey area?
Adjusted with the slide. Fewer turns means more area covered per battery.
Upon Completion
Return To Home
What should I do after completing the mission?
Safety and not losing your drone. Once completed, the drone will go back to the home point automatically.
Advanced Setting
Set to
Question to Ask Yourself
Reason
Target Surface to Takeoff Point
0
Is the terrain I want to survey at a different altitude than my homepoint?
Unless the terrain you are surveying is at a very different altitude than your takeoff point, leave this setting at 0.
Side and Front Overlap Ratio
~80%
How much should each of the images overlap each other?
This provides enough overlap so if some images are missing or poor quality while still building a contiguous model. The lower the detail on the surface below, the higher your overlap should be. If you have a large area to survey, you can reduce the horizontal overlap (no lower than 60%) to increase the area you can cover per battery.
Margin
0
How much margin do you want to leave around the survey area?
Provided your flight boundary covers the entire area you wish to survey, you don't need any margin.
Photo Mode
Distance Interval Shot
What metric is used to capture images?
Distance shooting allows the drone to capture images with consistent overlap.
Custom Camera Angle
Disabled
N/A
Keeping this setting disabled will ensure your camera angle stays nadir (-90) and ideal for mapping.
Route Start Point
User Preference
Where do you want your mission start point to be located?
Tapping the points on your mission boundary will allow you to set the start point location and update your flight route. Conserve battery by selecting the most ideal start point relative to the takeoff location.
Takeoff Speed
User Preference
How fast should the drone take off?
Faster takeoff speeds will slightly reduce the battery voltage but may be necessary on active sites.
11. Tap the save icon on the left side to save your settings.
12. Navigate to the camera settings by tapping the live camera view. The map and camera view will switch places.
13. Adjust the camera settings as described in the table below. If you happen to encounter settings in the app not mentioned in this table, you can leave them at their default.
Note that in winter, or in low light conditions, there are special considerations to make. You may need to slow down the flight speed of the craft (to less than 10m/s) and adjust the shutter speed to 1/800 or 1/500 to allow enough light to hit the sensor.
Failure to do this can result in a high ISO and will reduce the quality of the images you capture.
Camera Settings
Set to
Question to Ask Yourself
Reason
Mode
S (Shutter Priority)
How should the exposure be controlled?
To avoid motion blur. Shutter priority tells the camera that a fixed shutter speed must be used. The camera can adjust the exposure with aperture and ISO.
Auto Exposure (AE)
Unlocked
Can the camera auto-adjust exposure?
This needs to be unlocked for the camera to adjust the exposure with aperture and ISO.
Shutter Speed
1/1000
How fast should the shutter close?
1000 is usually a good starting point for sunny conditions. In low-light conditions, reduce the shutter speed to ~800 and lower the speed.
Focus Mode
AFC
N/A
PLEASE NOTE: The M3E and M4E will automatically switch to Manual Focus (MF) at the start of each mission. This is expected, and no user input is required.
Images must be in a JPG format to upload to Propeller.
Lock Gimbal While Shooting
Enabled
Do you want the gimbal to lock in place while it takes a photo?
Leave this on its default setting. This will help prevent blurry images.
Mechanical Shutter
Enabled
Do I want my camera to use the mechanical shutter?
A mechanical shutter uses the conventional front and rear shutter curtains at the front of the sensor. Not using the mechanical shutter will introduce distortion.
Dewarping
M3E - Enabled M4E - Dewarping is off by default in M4E, which is the expected behavior.
Should dewarping be applied by the camera?
This will help improve the accuracy of your data depending on your drone model. PLEASE NOTE: Even when the dewarping setting is enabled, dewarping will always be off for photos taken with the M4E during a mission.
14. Double-check your settings in the Preflight Checklist and ensure Dewarping is ON (M3E) or OFF (M4E) for best results. The Preflight Checklist will appear when you start your mission.
Check the airspace on your site before you arrive, and remember to charge your AeroPoints and drone batteries before your mission.
I still can't do it!
We wrote these articles to equip you with everything you need to get the job done on your own, but we understand that sometimes this isn't sufficient.
If you're stuck, the Propeller hardware support team may be able to help. You can contact them by emailing hardwaresupport@propelleraero.com.au.