DRAFT

Appendix D Litchi

Litchi is one of the Drone 360 Apps you can use to take 360 photos with your drone. When triggered, the app will take control of the drone and take a series of still photos that can be stitched together to create a 360 panorama. In addition, the iOS version of the app can stitch the images into a 360 after the flight.

D.1 Pros and Cons

Features that people like about Litchi include:

  • the Litchi mobile app is available for both iOS and Android.

  • Litchi is designed for videographers who want to do complex video sequences that would be challenging to capture manually. Litchi supports many flight modes and waypoint actions including 360 panoramas.

  • The “Auto Pano” button on the app will take control the drone during a flight to take a series of photos with enough overlap to stitch well. The default settings work well, but you can adjust the settings to take more or fewer images.

  • Missions can also be designed on the app or before you go to the field on the Litchi website (called Mission Hub). Missions created using the website will be synced to the mobile app, after which you can use the app to fly the mission. (Note however that as of early 2021 the web-based mission planner still can not take enough photos at a waypoint for a full 360 panorama, only a single wrap-around panorama).

  • Waypoint missions can be saved and repeated for monitoring programs. They also make it easy to share your mission with other users.

  • The Litchi app for iOS can stitch 360 images after the drone lands, so you can check the quality while you’re still in the field.

  • The photos Litchi takes are saved on the memory card on the drone, so you can download them after the flight and stitch them with your own software.


Limitations of Litchi include:

  • It only works with a handful of DJI drones (including the DJI Mavic, Phantom, Inspire, and Spark)

  • The iOS and Android app costs $25 each. If you want to use it on both Android and iOS devices, you have to buy both versions of the app.

  • The number of features and options steepens the learning curve and takes a while to get used to.

  • In-app stitching is only supported on the iOS Mobile App (note this feature is expected to be added to Android app in early 2021).

  • Although you can add a series of actions to a waypoint mission to take photos at different angles, you can only do this at one pitch so it won’t be a full 360 panorama. To take enough images for a full 360 panorama, you have to end the current mission (or fly manually to the desired location), and manually click the Auto Pano button on the app.

  • Litchi does not support photogrammetry (mapping) missions.

D.2 Litchi Tips and Tricks

  1. If you’re new to Litchi, check out the getting started videos. It’s not a simple app to use. Practice creating a simple waypoint mission using the app before you start planning missions via the Mission Hub website.

  2. Some people report conflicts if DJI GO and Litchi are running simultaneously. If you experience this, after you’ve done your pre-flight checks with DJI GO (i.e., verify the RTH altitude, check camera settings, etc), force close the DJI GO app and start Litchi.

  3. As with any app that flies your drone, learn how to take over control during a flight, and practice to make sure that works. You don’t want to be fumbling around to take control as your drone is flying off into the sunset. Using the toggle switches on your remote controller is generally a more sure-fire way of taking manual control than buttons on an app.

  4. To test out Litchi’s panorama functions, start by flying manually to a location where you’d like to take a 360 photo, then press the Auto Pano button on the app. This button is visible when you’re on the ‘Pano’ screen (more info).

  5. For best results, take panorama photos when the sun is high in the sky. If the sun is low enough to be in some of the photos, it will be more difficult for the stitching program to match the exposure with other images.

  6. Try taking panoramas from a few different altitudes (e.g., 50ft, 150ft, 300ft) to find a good balance between how far you can see into the distance and the amount of detail in the images.

  7. If the stitching doesn’t turn out well, try to trouble shoot. Consider increasing the number of images taken (by increasing the amount of overlap), make sure you’re flying with enough light. You may also stitch the images in a program that allows you to edit the tie points (e.g., Hugin).

  8. To create a mission that takes a 7-shot panorama (see caveat below) in Mission Hub, select the waypoint where you want the photo taken and click the Panorama Preset button. This will add the necessary actions to take 7 photos.

Note: the 7-shot panorama you can program into a flight in Mission Hub is not the same as clicking the ‘Auto Pano’ button during a flight (which takes 23 images, including a nadir image). To get a full 360 image, do not use Mission Hub. You can however use Mission Hub to plan a waypoint mission, and when it reaches a waypoint switch to Pano mode on the app and use the Auto Pano button.