Let us format. Let us delete. Let Us Drone.

You and your son have been loving the trips to the park with the Spark and his bicycle. The training wheels have been on for weeks, and today is the day that little Jimmy makes the monumental transition to two wheels. As he is mounting that bright red Trek, you get ActiveTrack ready on your Spark, which will allow you to get the whole event on video while freeing up a hand if wobbly wheels prevail. Just as you hit the record button as Jimmy’s feet find purchase on welcoming pedals, an “SD card full” message pops up. You just transferred the old footage to your computer last night and deleted it from the SD card! What gives?

There are several occasions when formatting your drone's SD card is necessary. One such occasion is when you delete SD card files using your computer, but a glitch occurs where the files are hidden from view when you “delete” them, but they aren’t actually deleted. This was depicted in the story above and would call for an SD card format. To format the SD card, open the DJI Go 4 app and go to the camera settings. Click the rightmost tab and scroll to the bottom where you’ll see “Format SD Card”. Tap that and you’ll be good to go, with everything being erased from the SD card.

What does formatting an SD card mean?

If you haven’t spent much time in the world of technology, a term like “formatting” may sound all kinds of foreign to you. Put simply, formatting an SD card for your drone is the process of setting up a file management system so your camera will know where to place videos and images. This is exemplified in the creation of the DCIM (Digital Camera IMages) folder you see when you insert your drones SD card into the computer.

Will formatting an SD card delete its contents?

Yes, and no. Formatting your drones SD card will erase the file management system that was previously set-up. What does that mean for you? If you format the SD card using the DJI GO 4 app, remove the SD card from the drone and place it into the computer, you will not see any files on that card. The actual images and videos are still present (or at least parts of them if they’ve been written over by new data) somewhere on the card. Formatting the SD card gives the camera permission to rewrite over the deleted data. If you’re wondering how much space is available to use on the SD card after formatting it, the answer is all of it.

I watched a YouTube video that gives a good illustration of this. If you open a textbook to the table of contents and cover one of the chapter titles with a sticky note that says “empty” on it, the corresponding chapter doesn’t magically disappear. Just as you can’t see the chapter title in a book's table of contents, you can’t see any of the videos or images in the directory but they are technically still there. Here’s the video: https://www.youtube.com/watch?v=G5s4-Kak49o

If you want to ensure that the contents of a memory card are permanently deleted, you have two options: rewrite over the data multiple times until not even a trace of the old content exists, or you can physically destroy the card.  

Is there a difference between formatting and deleting?

As we learned above, formatting an SD card tells the camera to set up a new file management system. In doing so, the old file system and all of its contents will be “deleted” (remember, the deleted content will still be momentarily present, there just won’t be anything pointing to it). Deleting gives you the option to get rid of select images or videos, leaving the file management system unaltered. You can delete individual images or videos from the app or on the computer when the SD card is inserted.

When should I format my drones SD card?

Similar to the post where I covered IMU calibration, DJI doesn’t talk much about formatting your SD card. So let’s talk about the times it may behoove you to commence the formatting process:

• Every time after you transfer your images and videos to your computer.
• If the app gives you an SD card error. There may be a glitch in the card and formatting it may rectify this. If formatting doesn’t do the trick, consider upgrading the SD card.
• When you get a new SD card. There’s talk as to if this is necessary, but formatting a new card ensures that your drone will be able to correctly write data to it.
• If you get a max capacity error after you have already removed the old images and videos.

• If you accidentally turn off the drone while you are still recording a video. Although this hasn’t happened to me, some have reported that video files were corrupted when they turned off the drone while still recording. Just remember to backup all of the card's contents first.

• If you want to maintain the cards full speed performance potential. Periodically formatting the SD card is like doing a deep-cleaning of your house after you’ve been opting to simply “straighten-up” the last few months.

How to format the SD card?

Before formatting the SD card, ensure that you have already backed up any images or videos that are currently on the card. It is good practice to format the SD card within the DJI GO or GO 4 app. Why is that? FAT32, exFAT, and NTFS are different types of file systems, and if you format the SD card on a computer that has a default file system that is different from what your drones camera prefers, you may get errors upon trying to use that card. Yes, I understand that there are workarounds to make formatting on a computer work efficiently, but the average drone user just needs to know that formatting within the app is recommended.

Fortunately, formatting an SD card within the app is simple. As mentioned above, turn on your remote controller, open the DJI GO or GO 4 app and power up the drone. Tap on the camera settings and click the rightmost tab. Scroll down to the bottom and you’ll see “Format SD Card”. Tap that and give it a second; naturally, this may take a bit longer if you have a lot of data currently stored on the card.

Can I format the SD card to allow the camera to record videos larger than 4GB?

The simple answer: no, not yet at least. You may have learned after you recorded a fifteen-minute time-lapse video of the sunset that the video was broken up into two or three shorter videos. At least that’s how I found out that DJI will only allow a single video file to be a max of 4GB in size.

The FAT32 file system only allows single videos up to 4GB, which had many DJI drone users turning to their computers to format their SD cards with the exFAT file system (which does not have the 4GB single file size limit) in hopes of recording longer videos. However, even with the exFAT format, the camera will still break up long videos into 4GB chunks. Bummer.  

This is even more of a bummer for users of older DJI drones like the Phantom 3 Pro where frames would be dropped between videos that were broken up, so the video wouldn’t look all that smooth when stitched together. DJI has since fixed this issue with their newer drones. Now we’ll anxiously wait for DJI to allow us to record an entire sunset timelapse without having to do any stitching.  

Can I retrieve pics or vids if I accidentally formatted the card?

You wouldn’t be the first if you accidentally formatted an SD card or deleted some of its contents. Luckily for us, smart people have created recovery software that is designed to bring back that content you put in a state of purgatory. The fact that “deleted” content can be “un-deleted” shows us that content isn’t truly gone until it is written over with new content.

To see if this was possible, I did an experiment of my own. After formatting my SanDisk Extreme Plus 128GB card, I downloaded Disk Drill, a recovery software made for Mac and Windows. I ensured the card was indeed empty before proceeding with the recovery. Following the instructions on the software, I sat back and watched as my images and videos were resurrected. It worked!

Now, I’ll say that the free version of Disk Drill only allows you to preview the recovered media. If you’d like to actually get the data back, you’ll have to buy the pro version for $89. This was by no means a thorough test and I’d encourage you to do some research on different recovery software options out there as I’m sure some work better than others for different applications (Windows vs. Mac, etc.).

Trevor’s Take

Don’t be like that guy who didn’t get video of little Jimmy’s first time on a bike without training wheels! Life is about making mistakes and (hopefully) learning from them. If you’ve learned something from this post, then maybe an SD card format mistake isn’t one you have to make. I didn’t dive into the brand or type of SD card to use, but there are cards that have been proven to work better with DJI drones than others. A quick Google search will yield a plethora of information on this topic. Keep those props and camera rolling!