Error transferring images to SD card

Hi Pix4D,

 

I did a survey using Double Grid but when checking the images on the SD card, I saw that they are not transferred correctly.

The app shows that it took around 500 pictures but only 300 are on the SD card.

The last few pictures are very distorted as well (enclosed).

I did another survey afterwards, and everything seems fine then.

Is there a way to still get the pictures from the other survey and what could have been the issue?

Is it an issue with the drone, SD card, the app, …?

Thanks a lot, 

Siegmund

Hi Siegmund, 

The images are directly saved on the SD card by the drone, so we can’t restore it when it’s not recorded on the SD card. In most of the case on the iOS system, this happens when the connection between the drone and the remote controller/app.

The interactions between the drone and the app during a mission are as follows.

  1. The app receives the GPS location of the drone (drone to the device).
  2. The app decides to take a picture according to the new location and asks the drone to do it (device to the drone).
  3. The drone may or may not take a picture, even though usually it does.
  4. The drone sends back a message to say that the picture was taken (drone to the device).
  5. The app shows the camera icon at the position of the drone when the message is received.

Therefore the camera icons on the flight track of the grid do not always correspond to the exact location of the photos where they were taken. Indeed some delays may happen in steps 1, 2 and 4 described above. It can happen that the camera fails to shoot (step 3.) but still sends a callback to say the image was captured, which results in fewer images on the SD card. The solution would be decreasing the speed of the drone or capturing the image with Safe mode.