Once I've offloaded pictures and videos from the microSD, I can save the step of formatting the card in the UAV (which involves powering up the mobile device, RC & UAV) by deleting the subfolder(s) of X:\DCIM\ and deleting all files under X:\MISC\ and its subfolders. The microSD is then left with the same folder structure and free capacity as after using the format function in the UAV.

FYI: Image thumbnails appear to be stored in X:\MISC\THM\ directory and take up card space even though the corresponding pictures and videos have been removed.

FYI: This may change with F/W or DJI Go application updates so be advised.

What I've been doing over the past several months is taking the videos/photos off the disc by doing a cut and paste rather than copy and paste, so after the files are at their destination, the SD card is pert'near empty.

I don't do this to keep from formatting the card so much as to keep the files at the root, such as the firmware BIN file, which I like to leave around for at least a couple of weeks after a firmware upgrade to be sure all of the batteries get updated.

Chris

Just format the card while you have it connected to your computer.
It's fast and easy.
There is no need to leave any folder structure as the Phantom puts that on automatically.
If you just delete rather than formatting, you end up with "cobwebs" accumulating.

labroides@yahoo Posted at 2016-6-7 15:48
Just format the card while you have it connected to your computer.
It's fast and easy.
There is no n ...

RE: "... 'cobwebs' accumulating."

Ah! Another superstition.

Making claims without evidence is not good for the reputation.

This forum is in dire need of Mythbusters.

The battle of the masters.

Airspace Explor Posted at 2016-6-8 11:02
RE: "... 'cobwebs' accumulating."

Ah! Another superstition.

And I suppose Lexar wouldn't know anything about their cards either?
Look at the last tip here:  http://au.lexar.com/content/lexar-memory-card-tips

Or ....
http://www.apotelyt.com/photo-memory/formatting-flash-media
https://support.nikonusa.com/app ... g-format-and-delete
http://improvephotography.com/67 ... about-memory-cards/
http://petapixel.com/2012/03/07/ ... mory-cards-healthy/
http://www.kehblog.com/2012/03/m ... ty-error-codes.html
http://digital-photography-schoo ... m-your-memory-card/

Making claims that something is superstition without any evidence ... etc etc

labroides@yahoo Posted at 2016-6-7 18:29
And I suppose Lexar wouldn't know anything about their cards either?
Look at the last tip here:  h ...

What you're seeing may be specific to Lexar products.

I'm using the microSD that came with the Phantom 3.

Airspace Explor Posted at 2016-6-8 11:35
What you're seeing may be specific to Lexar products.

I'm using the microSD that came with the Ph ...

It does not matter what card you are using, the aircraft does not look at the card maker and decide how it will work.

Labroides is correct, the best course of action is to format the card after you have copied all the files off. Copying/Cutting/Pasting makes no difference to the operation, the problem lies within the File Allocation Table, because the entries for each file giving the sector data for writing become fragmented.

And before someone decides to tell us that a solid state memory cannot become gfragmented, yes it can. Not in the sense of a physical hard disc, where the heads have to jump all over the place to write a file, but in the manner that files are not being written as contigous blocks, and therefore the writing process takes longer. And with the current situation of high bitrate files being written to slowish memory in MicroSD cards, you can end up in a situation where the card cannot keep up with the required speed of the writing process.

Formatting the card resets all the entries in the file allocation table to contigous blocks and makes the process easier for the device in the aircraft writing the files. The processsor can then make use of speedier writing routines that write very large blocks consecutively.

By the way, CUT AND PASTE has a danger that some people don't think of.  I was warned early on in digital photography about doing it.  On a rare occasion, you may have a failure on the destination drive and lose the files.  A photog friend lost some important files this way once.  After that, he always copied and then went back to delete.  Personally, I frequently take my chances and do the cut/paste.  If the pix/vids are special, I'm more careful and copy first.  Generally, I format in the P3, even if I did it already on the 'puter.

Why you bother with this instead of just formatting the SD card when it's in your computer?

About the "cut n paste",   there is the possibility that your computer crash or some kind of accident happen, then you lose your file.

huntcool001@gma Posted at 2016-6-7 23:46
Why you bother with this instead of just formatting the SD card when it's in your computer?

About t ...

At least one pilot indicates he keeps the bin file on the microSD but wants to free up space for more image work.

Some people may want to retain the hidden update log files for a period of time as well.

I'm pointing out that some additional space can be recovered after files in X:\DCIM directory are removed by removing corresponding files in X:\MISC\THM\ directory as well.

It'll be the subject of another test to determine if the *.thm & *.r?? files are auto removed by the Phantom when it detects the corresponding *.jpg, *.mov, *.mp4 file has been deleted by an external device.

I will say the p3a does look at the type of sd card.  I say this because I inserted an older 16gb card that was not class 10 or UHS and it barked about it.

When I copy (or cut), I do the entire root directory, in case I later need any of the files in either directory.  I copy the contents into a new folder that contains the date and subject of the flight for future reference.  I.E.:  2016-0608 Checking Out The Canal

walterm Posted at 2016-6-9 02:57
I will say the p3a does look at the type of sd card.  I say this because I inserted an older 16gb ca ...

Yes, the system does a test on the card to determine if it is fast enough for the job. But I said it did not determine the 'maker' of the card and act accordingly.

labroides@yahoo Posted at 2016-6-8 03:29
And I suppose Lexar wouldn't know anything about their cards either?
Look at the last tip here:  h ...

Sorry, I read only the first two links. Nonetheless, in no way those are suggesting that deleting files will leave unwanted, unuseful, dead good-for-nothing files.

cloudycante Posted at 2016-6-9 16:03
Sorry, I read only the first two links. Nonetheless, in no way those are suggesting that deleting  ...

Read a little further then ... I put them in because they do back up the idea that formatting is good.

labroides@yahoo Posted at 2016-6-9 08:34
Read a little further then ... I put them in because they do back up the idea that formatting is g ...

still nothing, sorry.

The closest I find is the hint to format instead of delete, because otherwise the cameras could have some internal db error, which is of course true only for cameras that store db files along with images on the memory cards.

Let all the rest aside, the thing is that memory cards have limited read/write cycles, and formatting them may lead to decrease span of life.

cloudycante Posted at 2016-6-9 18:00
still nothing, sorry.

The closest I find is the hint to format instead of delete, because otherw ...

"memory cards have limited read/write cycles, and formatting them may lead to decrease span of life."
OK ... your turn.  
Can you find me something to back that statement up?

labroides@yahoo Posted at 2016-6-9 10:08
"memory cards have limited read/write cycles, and formatting them may lead to decrease span of lif ...

ehm... do the water boil at 100° C ? :-)

cloudycante Posted at 2016-6-9 18:16
ehm... do the water boil at 100° C ? :-)

The boiling point of whater is well known and can be checked anywhere but your suggestion that formatting an SD card can decrease its life sounds unlikely and I can't find any reference to support it.
If you throw statements like that as if they are fact, you have to back it up.

labroides@yahoo Posted at 2016-6-9 10:59
The boiling point of whater is well known and can be checked anywhere but your suggestion that for ...

gosh, I'm sorry, but I truly thought it was pretty well known.

To point you to the first link I can think of:

https://en.wikipedia.org/wiki/Secure_Digital

Risks of reformatting[edit]

Reformatting an SD card with a different file system, or even with the same one, may make the card slower, or shorten its lifespan. Some cards use wear leveling, in which frequently modified blocks are mapped to different portions of memory at different times, and some wear-leveling algorithms are designed for the access patterns typical of FAT12, FAT16 or FAT32.[96] In addition, the preformatted file system may use a cluster size that matches the erase region of the physical memory on the card; reformatting may change the cluster size and make writes less efficient.

labroides@yahoo Posted at 2016-6-9 18:08
"memory cards have limited read/write cycles, and formatting them may lead to decrease span of lif ...

And do you know what that finite number of cycles is?
My research suggests it's about 10,000 times.
Which would allow formatting every day for 27 years before you have to worry.
And if your card uses wear levelling, you can stretch that out to about 300 years.
If formatting your memory card was really a problem, the manufacturers would be telling you not to do it.

http://www.dpreview.com/forums/thread/2908272

Airspace Explor Posted at 2016-6-8 22:19
At least one pilot indicates he keeps the bin file on the microSD but wants to free up space for m ...

I think both P3 and P4 have the log files hidden on a 4GB sd card built into the plane body, not on the user's SD card.  P3 though has an update log file on user's SD card.

So formatting your own SD card wound't affect the retention of flight log.

labroides@yahoo Posted at 2016-6-9 11:44
And do you know what that finite number of cycles is?
My research suggests it's about 10,000 times. ...

I'm sorry but:

- 10k is a very little number when you're talking RW cycles
- level wearing makes things even worst if you format every time, because it tries to level all blocks to the most worn out (as of course it can't obviously make them less worn out)

that is why is actually a bad idea to format instead of delete.

That said, nowadays format isn't really format and most of the times it just creates a new filesystem, because storage devices (hard drives etc..) have become too big and it'd take forever otherwise.

Nonetheless, I believe we've lost a little of the point here: you said one should always format because otherwise on'd be left with cobwebs, which is frankly far from being proved and so far it's clear deleting targeted files instead of formatting has it's own advantages, while formatting can be even harmful (even though less and less so).

All in all, I believe the OP has all the rights to share his opinion on how to save a little time, as maybe a little naive as it might be.

cloudycante Posted at 2016-6-13 00:37
I'm sorry but:

- 10k is a very little number when you're talking RW cycles

After deleting the files from your Sd card just check the card info.  If the free memory is correct, there is no need to format. If the memory is not is not correct then the FAT is corrupted and you need to reformat.

I think a corrupted FAT is what someone means by cobwebs. Non-contiguous files occurs when a file exists, a new file is created and then data is added to the first file. That is not the case when you delete the files.

skipilot1 Posted at 2016-6-12 19:10
After deleting the files from your Sd card just check the card info.  If the free memory is correc ...

Well... Of course :-)

If your SD gets corrupted, then you've no other option.
Of course when that happens, it might just mean that your SD (and flash drives in general) has just reached its EOL.
That is also one of the reason you're not supposed to run OSes from sdcards or thumb drives. They die so much sooner than a normal HD. A common trick is to store /tmp, /var/tmp etc.. in ramdisk but let's face it, it might be just a palliative :-)

Not A Speck Of  Posted at 2016-6-7 21:29
What I've been doing over the past several months is taking the videos/photos off the disc by doing  ...

If you do it that way and the cut/paste process gets interrupted your screwed, so not a good idea at all.

Swedrone Posted at 2016-6-13 03:33
If you do it that way and the cut/paste process gets interrupted your screwed, so not a good idea a ...

And yet, that's what a DJI employee told me to do on these forums when I complained about the SD card getting an "Index Full" error in flight (even when the SD card is near empty), if I didn't format the card between copies.

But in general, a cut and paste does not delete the source file until the target file has been verified as closed (completed). I haven't had a cut and paste issue like you describe in decades; and it wasn't an operating system error, it was a application file handling error.

Chris

Not A Speck Of  Posted at 2016-6-13 09:21
And yet, that's what a DJI employee told me to do on these forums when I complained about the SD ca ...

After you copy the files and delete them from the SD card, you must empty the trash bin before ejecting the SD card from your computer. Otherwise the FAT does not release the space and your card fills up. Next time, delete the files and check the info. You will see that the available space is less than the SD card's total memory. After you empty the trash bin check the info again and you will see that the full space is available.

There is no need to reformat the card every time. I have had several drones by different manufacturers and the process is the same for every one of them.

skipilot1 Posted at 2016-6-13 14:26
After you copy the files and delete them from the SD card, you must empty the trash bin before eje ...

'There is no need to reformat the card every time. I have had several drones by different manufacturers and the process is the same for every one of them.'

You are quite correct, there is no need to re-format the card every time, however if you make a habit of cutting/deleting files off an SD card you will soon arrive at the DJI error 'Index Full' or get to the point where the system simply stops writing to the card when recording video.

How an SD card is treated or handled inside the aircraft bears no relation to what happens to it in a computer, because the aircraft system does not implement all the functions you would have available to you in a full blown computer like the TRIM function.

The whole process of reading the sensor, encoding the files in H.265 and writing the file to the SD card is handled in the Phantom by a single large FPGA chip, and while it is very clever and fast, it does not have all the niceties available, particularly buffer memory. If you are shooting 4K video, the system is trying to write data at around 60 Megabits per second to the SD card. It can sustain that rate as long as the SD card is rated fast enough to do the job, and also as long as the File Allocation Table on the card is making it easy to do so by arranging the memory blocks to be in consecutive locations.

But if the card has been used for some time with you cutting the files or deleting them, the memory blocks are now located all over the card, and this slows down the writing process to a small degree, as the FPGA chip needs to enquire the location of each block to write it, and it takes a bit longer each time if the blocks are not contigous or one after the other. SD cards have a feature that allows large blocks of memory to be written at a time, providing the blocks are contiguous. This will not work on a fragmented card, and yes, cards can become fragmented just like spinning hard disks do.

If this process slows the process too much, and the card is not fast enough, eventually the FPGA over-runs its very small buffer and cannot sustain the process. In some high-end cameras, it would solve that problem by skipping frames, but it cannot do that easily once the frames are encoded in H.265, so it simply stops recording.

A further point about formatting a card using up write cycles, a so-called 'quick-format' simply writes a series of nulls to the File Allocation Table, it does not write the entire memory space of the card, so the impact is very small. And this has already been thought of by providing two copies of the Fille Allocation Table.

Geebax Posted at 2016-6-13 13:51
'There is no need to reformat the card every time. I have had several drones by different manufactu ...

So is the best answer to format after a certain number of file deletes?

I still question the deleted-folder / trash-can keeping a lock on the FAT for removable media. I don't have to do this for SD/CF cards for other accessories such as my cameras.

Although there could be a difference in the OS, Windows vs. Mac (I'm on Win7).

The Phantom is the only removable media device I've had with this issue.

Chris

Not A Speck Of  Posted at 2016-6-13 13:34
I still question the deleted-folder / trash-can keeping a lock on the FAT for removable media. I don ...

The Phantom has no proven issue.

Not A Speck Of  Posted at 2016-6-14 06:34
I still question the deleted-folder / trash-can keeping a lock on the FAT for removable media. I don ...

The Phantom does not necessarily have an issue, as long as you have an SD card that is fast enough, it normally will not arise. However there are other cameras out there where the writing speed of the camera borders on the maximum capabilitiy of the SD card, and it does become an issue. This is the case with the Blackmagic Pocket Cinema Camera, and it is a well known issue for that camera.

In the case of the Phantom, the Sandisk Ultra series cards are barely fast enough to cope with 4K recording, and can exhibit this problem, while the Sandisk Extreme series are OK.

It is worth remembering that it does not happen when a camera is taking still shots, only when recording a stream of video, and then only when the recording bit rate is high enough.

Not A Speck Of  Posted at 2016-6-14 04:34
I still question the deleted-folder / trash-can keeping a lock on the FAT for removable media. I don ...

I use a Mac so maybe it could be a Mac issue. That is just my experience.

Airspace Explor Posted at 2016-6-14 05:53
The Phantom has no proven issue.

Yeah it does (have a proven issue). DJI confirmed it. Told me to always format, or use the cut and paste. So long as I just copied the files off, then deleted them manually from the SD card after the copy, I was going to get the "Index full" error. I got it several times.

In the field resolution: just format the card from the Go menu. But at that point, it makes you wonder "Did I or didn't I copy them all off the card last time". Without the error, that ill-confidence wouldn't occur.

Geebax, you're talking about card speeds, which isn't my issue at all.

I see skipilot1 chimed in that the trash-can aspect may be a Mac thing. Thanks for that, and this is not a blocking issue for me. I just commented on it as feedback to someone else's post (now long forgotten).

Not A Speck Of  Posted at 2016-6-15 05:03
Yeah it does (have a proven issue). DJI confirmed it. Told me to always format, or use the cut and ...

'Geebax, you're talking about card speeds, which isn't my issue at all. '

In your case, this is an issue with DJI of poor software coding, they create a file that is not self-scavenging. A good programmer sets up log files to have a given maximum size, and when it is reached, the file prunes itself automatically. the 'index file' in the Phantom is not doing this presumably.

Geebax Posted at 2016-6-15 06:45
'Geebax, you're talking about card speeds, which isn't my issue at all. '

In your case, this is an ...

That sounds right.

Not A Speck Of  Posted at 2016-6-14 12:03
Yeah it does (have a proven issue). DJI confirmed it. Told me to always format, or use the cut and ...

So you're telling us that DJI told you that cut and paste is OK?

After you cut and paste, how many files remain on the microSD card? Include all files in the hidden MISC folder as well in your count.

Airspace Explor Posted at 2016-6-15 09:46
So you're telling us that DJI told you that cut and paste is OK?

After you cut and paste, how man ...

I have been just cutting from the DCIM folder, keeping the root and all other folders intact.

I realize some of the other folders could have been piling up small files, but since I use 64GB cards, they haven't been filling up.