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Mavic 4 pro creators transfer rates to PC?

SamHir

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So I've had it a few weeks already and am really pleased so far.

One weird thing that I noticed which I now can't replicate is that the first series of test shots (both video and photo, all sorts of quality and settings (jpg, raw, dlog, normal, dlog+ or whatever) transferred at an amazing rate on the first set. Something like 700+mb per second. I was also using the thicker USB C cable that came with the drone. I transferred about 10gb of data at that speed that first time. I was so impressed that I thought that it must be something about the newer drone that made it better? (better USB cable provided, better storage speed, etc.)

Since that first time, I have not seen anything remotely near those numbers, using the exact same equipment, the same way. I'm not getting more like I was getting on my Mavic 3 Cine, around 50mb per second).

The only thing that changed from the first transfer and subsequent ones was there was a firmware update that came out.

Anyway, not sure if that first time was a fluke or something, but I can't figure out if there's something else that I'm not looking into to get it to transfer that fast again. Curious what everyone else is getting with their internal storage being transferred via USB C to an external device.
 
Just transferred over 80gb data and its running at 35mbps its Terrible slow..... something doesn't seem right at them speeds , maybe its a Bug with that new firmware.
 
Just transferred over 80gb data and its running at 35mbps its Terrible slow..... something doesn't seem right at them speeds , maybe its a Bug with that new firmware.
Did you happen to notice the speeds previously? I only noticed because it was so incredibly fast that first time, otherwise I would not have even registered it...
 
Did you happen to notice the speeds previously? I only noticed because it was so incredibly fast that first time, otherwise I would not have even registered it...
I did the firmware right away as that is when I got the drone so no idea on the speeds before.
 
I solved my issue I wasn't using the Thick USBC supplied by DJI ! Speeds are now fast.
Yea usb-c cables are not all the same. Having the same physical plug for everything is great but a byproduct of that is lots of different cables that look the same are vastly different in their capabilities. Its even hard to find the right thing when you know what you are looking for.
 
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The other odd thing about USB-C cables they are not unidirectional, in respect to the orientation they are plugged into any device. Power output is different in different orientations as is data speeds. Now this is not all cables. There is a huge variation in the power and data rates with the cables. There is also a large fraction that the speed and power change with orientation. Just weird, but I assume it is an issue with wire types in let us call them "cheaper" cables. They most likely use only high speed and high power on one side's wiring so they are not technically lying about speed and power. I thought with USB-C I would only need one style of cable now. How wrong I was:
cables.jpg
 
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Were you able to compare read speed and write speed? I benchmark with CrystalDiskMark and get read speed in the 800-900 MB/s range, but only 200 MB/s of write speed. Using the DJI usb cable and any of the USB4 ports and USB3.2 ports on my desktop computer. I would expect the read and write speed to be closer than that. I would like confirmation from anyone that write speed are expected to be higher.

And yes, I confirm the usb-c cable makes a difference. I am not getting higher than 35 MB/s with cheap usb-c cables.
 
The other odd thing about USB-C cables they are not unidirectional, in respect to the orientation they are plugged into any device. Power output is different in different orientations as is data speeds. Now this is not all cables. There is a huge variation in the power and data rates with the cables. There is also a large fraction that the speed and power change with orientation. Just weird, but I assume it is an issue with wire types in let us call them "cheaper" cables. They most likely use only high speed and high power on one side's wiring so they are not technically lying about speed and power. I thought with USB-C I would only need one style of cable now. How wrong I was:
I'm not sure what you're meaning here but it's part of the USB-C spec that the USB-C to USB-C cables are bidirectional so it doesn't matter which way round the cable is plugged, it behaves the same. A USB-C cable is simply a port with a number pins connected by wires within the cable (there are no active electronics), those wires must be connected at both ends for the cable to function - if any of those wires are only connected at one end then they cannot provide their function whichever way the cable is connected because there is no connection to the pins. I've used a number of full spec USB-C cables and they work perfectly no matter which way round the cable is connected as they should from the USB-C spec, they deliver full power and other features like DP-alt.

There is a significant variance between capabilities of a USB-C cable because the USB-C port is just a port and isn't linked to any actual standard, the expectation was that a USB-C cable would be a minimum of USB3 but it can be anything. There's no labelling standard either so you generally can't tell what a USB-C cable can do without plugging it in. I have three USB-C cables here which all look the same but one is the full spec capable of PD and DP-Alt, one can do PD but only USB2.0 and no DP-alt while the third one is USB 2.0 with no PD. Unfortunately sellers don't often make it clear either so getting the right USB-C cable can be a pain.
 
I have all the nice little devices that measure the rates and power goin through the USB-Cable to & from devices. I got them due to some cable not working projecting 4K video on my projectors. IT was then I found if you flipped the orientation of SOME USB-C cables the speed and power supplied went way up or down, depending on how you started in the first place. I am aware what the spec says, but the reality is some manufacturers only comply on half the wiring in the connector. I have cut a few open just to check, and yes they are cheaping out. Yes it will do 40mbs and 5 amps in one orientation, but not the other. This is due to the wiring and the software in the connector itself. Especially ones that claim Thunderbolt capability, there is a tiny chip in the connector. Some are better than others. Apparently, I recently found out that some devices do a connection test for power and data when a cable is connected (GoPro 11-13 Black). The cable reports back what it can do and the device adjusts accordingly. Out of this small selection, not a one does the transfer speeds of 10 or 20 gas nor do they support PD charging when plugged in the wrong orientation. It is kind of a secret which way gives the best speeds. I have taken to putting dots on the side of the cable that does the fast transfer and high power with a sharpie. That way I don't keep getting the "Transfer Speed Not Supported" error. Which is very prevalent with 4K video if you don't have it just so.
cable copy.jpg
 
I'm talking specifically about USB-C to USB-C cables which have no way to tell which way they are connected hence they cannot have different capabilities depending on which way round they are connected. I notice that most of the cables in your second picture are USB-C extension cables which are not USB-C compliant and are usually recommended against because they cause problems, they may well be the cause of your USB-C problems.

I use single fully wired USB-C cables which work with everything, docking, PD, DP-Alt etc. and in any orientation, they work exactly as they should without needing a box of other USB-C cables.

It is certainly possible to have different numbers of wires connected to give different capabilities since as I mentioned above, USB-C is just a port specification not a protocol but the number of wires in the cable does not mean it can only be used in certain orientations.
 
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So I've had it a few weeks already and am really pleased so far.

One weird thing that I noticed which I now can't replicate is that the first series of test shots (both video and photo, all sorts of quality and settings (jpg, raw, dlog, normal, dlog+ or whatever) transferred at an amazing rate on the first set. Something like 700+mb per second. I was also using the thicker USB C cable that came with the drone. I transferred about 10gb of data at that speed that first time. I was so impressed that I thought that it must be something about the newer drone that made it better? (better USB cable provided, better storage speed, etc.)

Since that first time, I have not seen anything remotely near those numbers, using the exact same equipment, the same way. I'm not getting more like I was getting on my Mavic 3 Cine, around 50mb per second).

The only thing that changed from the first transfer and subsequent ones was there was a firmware update that came out.

Anyway, not sure if that first time was a fluke or something, but I can't figure out if there's something else that I'm not looking into to get it to transfer that fast again. Curious what everyone else is getting with their internal storage being transferred via USB C to an external device.
Buy an OTG cable rated for USB3.
 
I know, I used those, since they printed out their specs on the connectors for illustration. I have 2 4tb Sandisk SSD's and 2 2tb Crucial SSD's and again they change speeds depending on which way you orient the cable as you push it in. Just the fact I experience. I also get not enough power warnings on GoPro 11's and 13's depending on which way I put the connector in. Goes away if I put it in the other way. Just another fact I experience. I have 4 cameras on the airplane that collect data at 5.2K they have the same issues to the SSD's the cables are not all symmetrical in their outputs and data speeds. The ones from DJI for my Cine are, the ones that where supplied by Sandisk are. It is a pig in a poke on the ones I have purchased that are longer than .5m. Again I discovered the fluke in behavior when hooking up the projectors for demonstration at a meeting. I had bought longer ones to be more than .5 m away. It turns out a lot of misrepresentation on cable quality and on symmetrical data/power delivery.
 
There is no misrepresentation on symmetrical data/power delivery, it isn't physically possible for USB-C to USB-C cables to be directional, they have no hardware to identify their orientation. I've used a lot of different USB-C cables (we use them for computer docks) and I've never seen a single cable which behaves the way you claim. I suspect the non-standard cables you've provided pictures of which are known to cause such problems are the cause despite your claims otherwise.

To avoid doubt and confusion to others - USB-C to USB-C cables are not directional despite the claims above however different USB-C to USB-C cables do have different capabilities depending on how they're wired. So if one isn't working as expected, it's definitely worth trying another.
 
Well, I guess your milage varies. All I can say is I have a pile that have that behavior and a smaller one that does not. I have cut a couple open, since they proved themselves to be not as represented and found the two halves, which should have identical wire, not be identical. As I said I think some the less expensive and even a few of the pricey ones are not living up to the letter of their specs.

Look, I am not an idiot with these things. I own a company that designs and modifies aircraft for geophysics survey. They cost millions and we have racks full of equipment in them. It only became apparent when I was showing demonstrations of our capabilities at mining conferences. It took a dumb projector to make it apparent. I went through a box of cables and found the behavior to be in a good half of them. I then started hooking up the testers to them and found it did it with small cameras like the GoPro, which test USB cables on connection (go to the GoPro Labs page to get the scoop on it). The Name Brand SSD's and other units.

I am glad it is not an issue for you has been the cause of me tossing a small box of cables, which actually represented a great deal of money. I literally had to go through my collection, cable by cable and test them all out before I left for South Africa last month. If I took a bad one, I was very unlikely to find one that worked properly there in time for our meetings.
 
There is no misrepresentation on symmetrical data/power delivery, it isn't physically possible for USB-C to USB-C cables to be directional, they have no hardware to identify their orientation. I've used a lot of different USB-C cables (we use them for computer docks) and I've never seen a single cable which behaves the way you claim. I suspect the non-standard cables you've provided pictures of which are known to cause such problems are the cause despite your claims otherwise.

To avoid doubt and confusion to others - USB-C to USB-C cables are not directional despite the claims above however different USB-C to USB-C cables do have different capabilities depending on how they're wired. So if one isn't working as expected, it's definitely worth trying another.
There are at least some directional (by design) USB-C cables. They will be marked HOST and DEVICE or similar on the two ends. See photos below.
IMG_9692.webp

IMG_9694.webp


IMG_9693.jpeg
Remember that USB-C is just a physical connector type. Not a specification. Anybody can put whatever they want in there. It’s the Wild West out there so it absolutely wouldn’t surprise me to hear some cables work better in one orientation than the other even if not designed that way like the ones above. Flipping upside down too.
 
Absolutely bizarre update:

So I was talking to DJI customer service and they suggested finding another 3.2 USB C cable and testing it. Lo and Behold the transfer rate went back up to ~700mbps+. What I'm baffled by now is why did the USB cable that came with the drone do that for one transfer and then nothing above ~50mbsp? I can't imagine it got damaged somehow in such a short time and if so wouldn't it just not work?

I also noticed that the inside of the connector is orange. Does that mean it is a thunderbolt cord and not a normal USB one?

So weird...
 
Second update: decided to call DJI again and we did some further testing. The DJI cord no longer charges the drone either! It seems that something went wrong with my cord physically, though it is unclear what. I took a bunch of videos of the cord transferring data and failing to charge and sent it over which they are going to review... it will be interesting to see if they send a replacement.
 

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