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philipd

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About philipd

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    GH5

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  1. Hi I suppose a lot depends on the hardware in the camera and how the firmware might be optimized specifically for different cards. The Canon may also have a much larger buffer allowing it ride over dips in the card write speed. For example the GH5 has been tested to really only work with the newer standard for V60/V90 type cards and newer recording protocols and I suspect they've pretty much ignored all other older cards on the market, anything else that works is a lucky accident, whereas the Canon may not support this new standard (I don't know if it does or not) so might be optimi
  2. Hi Taken from https://superuser.com/questions/847016/performance-difference-between-sd-and-microsd-cards What I mean is, we might be lucky and have a card that whilst it isn't rated V90, seems to perform okay, we then buy 4 others the same and find they don't work reliably if at all. If it doesn't have V90 on it's label, then it isn't a V90 card, so whether it works or not is somewhat down to luck of the draw. The card could also be so borderline, that it will work for the first couple of shoots, then fail consistently on the third. The only way to have a V90 card is to
  3. Hi Just because they are identical doesn't mean they are of course. A lot of manufactures will buy in NAND memory from wherever is cheapest, and even if the same they will be differing quality. In the same way Intel CPUs are mostly the same with the best off the production line running and sold at higher clock speeds, NAND works in a similar way. Also as the NAND is used and bad blocks are mapped out, the speed and reliability will vary. If it works and it isn't a V60/V90 card, it's a lucky find, buying the exact same again you may not be so lucky. V90 cards are using the cream o
  4. Hi Good news, thanks for reporting back, and I've seen successes and failures reported on non V90 cards even if the speed rating suggests it would be okay, so it might be a luck of the draw a little bit. (My Sandisk V30 cards work fine with FHD at 200Mbits/sec but failed after 20 or 30 seconds at 400Mbits/sec for 4K but that was expected). I'd be inclined not to trust anything important to a non V90 card, but otherwise if it works it works. In terms of backup to two cards, Panasonic have stated in their manual insert update for firmware 2.0 that at least one card must be a V60 or better
  5. Hi Have you tried it out elsewhere? That could be some interference it is picking up and it might be very local? I've heard similar noises from DECT cordless phones. On my H1 though I've not heard any noise like that. It could just be faulty? Regards Phil
  6. Yes, it is in the white paper published by the SD Association, its a new protocol and hardware specification specifically for real-time video recording, so cards of certain age could never have this addition anyway as it wasn't invented :-) It isn't just another way of advertising the speed of the card, it denotes the card supports the new video recording protocol that is optimised for video recording. The card enters a different mode of operation for video recording on cameras that also support this standard. Other cards may work absolutely fine but unlikely, the problem is cards
  7. Hi Of course it depends if the final GH5 restricts use to V60/90 cards only or attempts to write to any card on a best effort basis as to whether we have a chance with any fast card. We know already that a Sandisk 95MB/sec UHS-I card, so that is a 760Mbits/sec data-rate, almost double that actually required for 400Mbits/sec All-Intra, failed, that was tested by this site. So there is a world of difference between the marketing of these cards and what they achieve in reality. It may well be a V60 card isn't even enough or 100% reliable as that is 480Mbits/sec, so not much headroom,
  8. Hi Copying files are not a true test to see if a card has a sustained data-rate suitable for high bit rate video, for example the copy may dip to almost zero bps then burst a lot higher, giving a high overall average but would break when writing real-time video that can't be halted or would see a buffer overflow. This is why they've introduced a new standard so we know the card will work at a sustained minimum. File copies are different to different to real-time streaming. Some details are in the white paper https://www.sdcard.org/downloads/pls/latest_whitepapers/Video_Speed_Class-
  9. Hi That is the footnote they put to that statement. It's basically something SandDisk has made up for marketing, as that card doesn't show a V rating, we know it doesn't support the new real-time recording protocol and there is no guaranteed minimum write speed. There are 2 problems with using cards that don't support the new Video (V) protocol. 1) The GH5 may not be able to reach or sustain the required bit-rates full stop unless the camera can switch to using the Video protocol mode with a supported card. The new protocol changes completely how the camera writes to the ca
  10. Hi All-Intra at 400Mbits/sec will need a card rated at V60 or better. Ignore all other marketing speeds or bench-marks of a card, they aren't relevant in this context. Unless the card says V60 or V90 it isn't going to work at 400Mbits/sec despite the advertised speeds. The V moniker means the card supports a new specially designed protocol for real-time video recording that allows these 'high' minimum guaranteed write speeds, the number after the V gives the minimum guaranteed write speed that the card will support when used with equipment that also uses the new protocol, which the GH5
  11. Hi With regard to V30, V60 and V90 cards, these specify a minimum write speed, regardless of the state of card (fragmentation, erased state etc) which is the important bit of course for real-time recording, so will be lower than the headline marketing speeds. Also it is important to note that to obtain these guaranteed minimum speeds these cards need to be written to using a different protocol, and the card itself needs to specifically support this protocol as well as the camera (of course the GH5 does). This means buying a card that doesn't show the V rating, because it appears fast en
  12. Hi Same here, but there is a problem with maintaining quality with 60P. All-Intra is essentially compressing each frame as a JPEG. At 400Mbits/sec and 60 images a second to create Jpegs from, that is 400/60/8 = 830KB approx for each image. Take any image at 3840x2160 pixels and save it as a Jpeg compressed down to 830KB and quality is going to suffer, and that's ignoring the fact these would be 10bit images, which being squeezed into 830KB just isn't enough space to give a benefit, and would likely look worse than the standard IBP at a lower bit rate. When looking at 24fps each
  13. Hi It is very likely the new ALL-I 400Mbits/sec recording speed will require V60 cards, and will refuse to work on any other card regardless of the claimed or achieved write speeds. V30/V60/V90 are new protocols/hardware changes, so it's not just a case of any fast enough card will trick the camera into thinking it supports a fast enough write speed, a V60 card reports to the recording device it's capabilities and handshakes, and the recording device then operates in different recording mode to guarantee write speeds. Basically many memory cards have played a marketing game with hea
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