Dump the microSD card

The cardinal rule with most things (especially tech): if you don't shop around then you will pay more. In the world of smartphones, everyone should be price matching. Those that don't get burned and pay a premium.

Could not agree more. It always makes me cringe when I see people paying double for something that a 5 minute search could have prevented. I watch some ebay auctions and purchases with awe. You'll see an item sell for $100, and on the next page a guy is selling the same thing for $40.
 
I did not know the write speed of the system was only 7.5mb per second. Is this for just the video? Does it write photo stills any faster? If not, it won't behoove "anyone" to use any card over the minimum of the write speed. Start buying any 20mbs card.
 
Interesting comments from all, thanks.

Having tried the new card I get absolutely no jitters from it at all, so happy with the product choice. As far as the price is concerned, whoop whoop to Amazon but I would rather buy in a store local to me. I've never bought from Amazon but do buy stuff online, but if I have problems with a purchase it is much easier to drive 10 mins than the aggro to return to sender plus I can get my grubby mits on it there and then and not have to wait for the post from God knows where, if that is, it doesn't get lost on the way ;)
 
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Or any "accessory" pricing. Don't get me started on the dummies that drop $100 on a super-duper-gold-plated HDMI cable because it says Monster on it.

LOL I was going to say exactly the same thing! Virtually *all* HDMI cables pass signals properly. If you spend a little more to get a higher quality cable (I'm referring to the actual construction of the cable - i.e., don't buy something flimsy) that's okay. But some of the prices one sees for "quality" HDMI cables is ridiculous.
 
Except that a faster, more expensive card will perform just the same.
Whatever card you put in, it can only take the data as fast as the Phantom's buffer memory will deliver it.
Yes the WRITE speed will not be helped, but READ speed is at 90 Mb/s that will help in transferring files to the computer.
 
......and get a quicker one.

I bought an iPad mini yesterday, did all the stuff, and took the bird for a flight.Mega pixel delay on the screen so back to the forums. Seems I needed a mini 2. So I rang the store who said I could swap it and pay the difference for a mini 2 - Result

Having recorded video on the stock card that comes with the P3P yesterday I was unhappy with the result, jittery and staggered - really bad. So while I was changing the iPad I looked for a faster card.

I ended up buying a Sandisk Extreme Plus microSDXC UHS-1 Card, 64GB, 80MB/s.

Price on the packet was $199.99 - I asked the guy if he could do better on the card, he said he would do $149.99, the same price as the 32GB card - so I went for it.

Went to pay for it all, the price on the computer came up as $249.99 - BARGAIN OF THE YEAR

Well done Daniel at Harvey Norman at Waurn Ponds!!

A very happy Fish
Faster is never a bad thing when it comes to reading and writing data, good to eliminate any potential bottlenecks where ever you can.
 
Standard systems engineering. If you want to optimise a system you must spend your money on the bottleneck, not on parts which are not the bottleneck, otherwise all you achieve is a loss of cash.:(

The image processor in the P3Pro is the Ambarella A9, a 2.5 year old 1st Generation 4K/UHD chip (Much deeper information here: http://forum.dji.com/forum.php?mod=redirect&goto=findpost&ptid=19599&pid=144431&fromuid=6139

First up video - All 4K/UHD video is recorded at 60Mbps, which is roughly 7.5MB/s. Any "Class 10" card is, by definition, capable of recording sequential data at 10MB/s. Spending more is your choice, but it will only help you when extracting data to your computer.

Still photography, particularly rapid fire or multiple exposure (AEB) generates much greater data, up to 200MB/s, but there appears to be a bottleneck in the firmware that restricts the SD card interface bus to "Normal Speed", 12.5MB/s (SD bus specification 1.0). The chip, at a minimum must support High Speed, 25MB/s (SDXC, SD specification 2.0), put potentially supports UHS-I SDR104 (104MB/s bus) and I have an inquiry into Ambarella to find out what the maximum bus speed they support.

SD Bus speeds can be controlled by firmware, and DJI may have chosen to restrict the SD bus to "Normal Speed" because they (mistakenly, IMHO) believe it will improve compatibility with older/slower cards. Alternatively, DJI may have chosen to throttle the SD bus because it doesn't matter for video, 12.5MB/s is plenty fast enough for video and photography is a secondary concern.

[DJI - I will be happy to field test beta firmware that enables faster transfer speeds]
 
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The image processor in the P3Pro is the Ambarella A9, a 2.5 year old 1st Generation 4K/UHD chip (Much deeper information here: http://forum.dji.com/forum.php?mod=redirect&goto=findpost&ptid=19599&pid=144431&fromuid=6139

First up video - All 4K/UHD video is recorded at 60Mbps, which is roughly 7.5MB/s. Any "Class 10" card is, by definition, capable of recording sequential data at 10MB/s. Spending more is your choice, but it will only help you when extracting data to your computer.

Still photography, particularly rapid fire or multiple exposure (AEB) generates much greater data, up to 200MB/s, but there appears to be a bottleneck in the firmware that restricts the SD card interface bus to "Normal Speed", 12.5MB/s (SD bus specification 1.0). The chip, at a minimum must support High Speed, 25MB/s (SDXC, SD specification 2.0), put potentially supports UHS-I SDR104 (104MB/s bus) and I have an inquiry into Ambarella to find out what the maximum bus speed they support.

SD Bus speeds can be controlled by firmware, and DJI may have chosen to restrict the SD bus to "Normal Speed" because they (mistakenly, IMHO) believe it will improve compatibility with older/slower cards. Alternatively, DJI may have chosen to throttle the SD bus because it doesn't matter for video, 12.5MB/s is plenty fast enough for video and photography is a secondary concern.

[Side,side note - I will be happy to field test beta firmware that enables faster transfer speeds, DJI]

Interesting, thanks for posting. So likely that the SD Card is not the bottleneck then.
 
Interesting, thanks for posting. So likely that the SD Card is not the bottleneck then.

The SD card is absolutely not the bottleneck. Myself and others have tested many cards capable of 60-90 MB/s sequential write for doing 5AEB J+R photos (roughly 140-150MB) and verified a maximum write speed of roughly 11.5MB/s, which is about the maximum speed you could expect from a SD bus set at "Normal", 12.5MB/s.

There is some debate about whether the bottleneck is in the A9 chip or the SDbus. If it's the chip, we are SOL for faster photography. If the limitation is the SD bus, that is controlled by firmware and DJI can enable faster SD bus speeds.

Double bonus - if DJI changes the firmware to enable fast bus speeds they can also enable taking pictures while filming video (which is fully supported by the chip), but presumably DJI has chosen not to enable because there is not enough bus bandwidth to record video and save pictures at the same time with the bus restricted to 12.5MB/s

[Disclaimer - I'm bulldogging this issue because the chip and camera are fully capable of so much more, and so much better peformance, the DJI has chosen to not enable, that could really make the camera stand out against the competition. Ambarella is the exclusive ship provider for GoPro, so it's a safe bet that GoPro will come to market with the camera firmware fully optimized, and will probably show up with the next generation Ambarella H1 SOC which is capable of 4K60 H.264 AVC, 4K30 H.265 EVC, and 1080P240.
 
The image processor in the P3Pro is the Ambarella A9, a 2.5 year old 1st Generation 4K/UHD chip (Much deeper information here: http://forum.dji.com/forum.php?mod=redirect&goto=findpost&ptid=19599&pid=144431&fromuid=6139

First up video - All 4K/UHD video is recorded at 60Mbps, which is roughly 7.5MB/s. Any "Class 10" card is, by definition, capable of recording sequential data at 10MB/s. Spending more is your choice, but it will only help you when extracting data to your computer.

Still photography, particularly rapid fire or multiple exposure (AEB) generates much greater data, up to 200MB/s, but there appears to be a bottleneck in the firmware that restricts the SD card interface bus to "Normal Speed", 12.5MB/s (SD bus specification 1.0). The chip, at a minimum must support High Speed, 25MB/s (SDXC, SD specification 2.0), put potentially supports UHS-I SDR104 (104MB/s bus) and I have an inquiry into Ambarella to find out what the maximum bus speed they support.

SD Bus speeds can be controlled by firmware, and DJI may have chosen to restrict the SD bus to "Normal Speed" because they (mistakenly, IMHO) believe it will improve compatibility with older/slower cards. Alternatively, DJI may have chosen to throttle the SD bus because it doesn't matter for video, 12.5MB/s is plenty fast enough for video and photography is a secondary concern.

[DJI - I will be happy to field test beta firmware that enables faster transfer speeds]

As side note, the camera is using 2 x ARM A9 + 1 x ARM 11 core (impressive really!). The ARM 9 cores are running ExpressLogic ThreadX RTOS with cutom libs from Ambarella, called AMBA. The SD speed is managed by the Soc drivers and DJI hasn't touched them (I hope!!) and I wonder who (and how) has discovered that is not in full speed. In the case of the camera there are lot of OOB activity (out-of-band) needed to record other info like THM, Logs and temp files in hidden dirs, during mp4 chunks writings. I don't think they are under clocking sd, but simply other costraint exist. Remember that the internal DSP need to process 40 rasterization for 14MPixel each sec (A/D 12bit x pixel) and then encode MP4 chunks (create p-frame, i-frame and so on). This means that SD is not the only player.
 
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PS: Ambarella Soc is used in GoPro Hero series too. This can lead to some hack ... :rolleyes:
 
As side note, the camera is using 2 x ARM A9 + 1 x ARM 11 core (impressive really!). The ARM 9 cores are running ExpressLogic ThreadX RTOS with cutom libs from Ambarella, called AMBA. The SD speed is managed by the Soc drivers and DJI hasn't touched them (I hope!!) and I wonder who (and how) has discovered that is not in full speed. In the case of the camera there are lot of OOB activity (out-of-band) needed to record other info like THM, Logs and temp files in hidden dirs, during mp4 chunks writings. I don't think they are under clocking sd, but simply other costraint exist. Remember that the internal DSP need to process 40 rasterization for 14MPixel each sec (A/D 12bit x pixel) and then encode MP4 chunks (create p-frame, i-frame and so on). This means that SD is not the only player.

Great info. The performance in video is acceptable and not affected by bus speed. The performance during rapid fire photography is really painful and is what suggests that DJI has locked down the SD bus speed to "Normal" (12.5MB/s) and not enabled "High Speed" (25MB/s). Why so painful? Bench measurements clock 5AEB J+R photos are captured in roughly 250ms, but take about 20 seconds on average to write to the SD card (roughly 11.5MB/s) During the 20 seconds the camera is locked up and not capable of additional photographs or initiating video recording.

The A9 SOC supports taking a picture while recording video, but DJI has disabled this, possibly because of bus bandwidth issues, that could be corrected by enabling faster bus speeds.
 
Great info. The performance in video is acceptable and not affected by bus speed. The performance during rapid fire photography is really painful and is what suggests that DJI has locked down the SD bus speed to "Normal" (12.5MB/s) and not enabled "High Speed" (25MB/s). Why so painful? Bench measurements clock 5AEB J+R photos are captured in roughly 250ms, but take about 20 seconds on average to write to the SD card (roughly 11.5MB/s) During the 20 seconds the camera is locked up and not capable of additional photographs or initiating video recording.

The A9 SOC supports taking a picture while recording video, but DJI has disabled this, possibly because of bus bandwidth issues, that could be corrected by enabling faster bus speeds.

I have no clue if this is right or not. You have correctly done some math about it.
The bus system on Cortex-A9 is quite complex (although easier than A15), but normally SDIO is a DMA peripheral that works partially indipendent by the core CPU and I can't say how it is inizialized by the kernel parameters.
About taking snapshot during movie recording: yes it can be done, but it's not a general rule. The sensor must be capable to do that without changing the A/D settings and need to start a double transfer via DMA to memory where DSP has access. Ambarella DSP has 700Mb/s bandwith capability while 4K takes "only" 60Mb/s ... so I think that it's only a matter of software. I'm taking it easy, the things are a bit more complex in the video/audio encoding world ...
 
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You paid $150 for that card? Holy hell you got ripped off. It's $62 on Amazon.

You did not get "Bargain of the year". lol!

Afraid to say, this man is correct.

I bought the same card a few weeks ago.

May want to do more research in the future before spending so much money. ;/
 
Can someone please tell me how I can view my videos. Do I have to keep the p3p all running and linked up. Can I view from my phone once I'm finished or do I have to upload it on to my phone memory first.
Thanks
 
Can someone please tell me how I can view my videos. Do I have to keep the p3p all running and linked up. Can I view from my phone once I'm finished or do I have to upload it on to my phone memory first.
Thanks

You have a sort of replay in DJI Pilot app. I suggest to download videos/photos on a pc/mac directly plugging your microSD with some adapter. This is the fastest way to see a full 4k video. Obviously your pc/mac must be power enough.
 
......and get a quicker one.

I bought an iPad mini yesterday, did all the stuff, and took the bird for a flight.Mega pixel delay on the screen so back to the forums. Seems I needed a mini 2. So I rang the store who said I could swap it and pay the difference for a mini 2 - Result

Having recorded video on the stock card that comes with the P3P yesterday I was unhappy with the result, jittery and staggered - really bad. So while I was changing the iPad I looked for a faster card.

I ended up buying a Sandisk Extreme Plus microSDXC UHS-1 Card, 64GB, 80MB/s.

Price on the packet was $199.99 - I asked the guy if he could do better on the card, he said he would do $149.99, the same price as the 32GB card - so I went for it.

Went to pay for it all, the price on the computer came up as $249.99 - BARGAIN OF THE YEAR

Well done Daniel at Harvey Norman at Waurn Ponds!!

A very happy Fish

The price of a hi-speed 32G card is about $40
 
And everyone here that has purchased a DJI branded over-priced quad or accessory has gotten ripped off by this QC deficient, warranty-dishonorable, customer service-lacking company for much more than this guys SD card. You are all so smart. DJI is the General Motors of "drones" and they pwned you all.
 

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