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Official Low GOP topic, series 2
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  • @proaudio4 I think another 100K on a frame is about the maximum you can get in this bitrate of 176M, but its likely to push it over the edge for a lot of SD cards ability to write it . As it is now, if you look at the test I did in the banding thread it is on a par image quality wise with cbrandins 66M AQ2 (though it is a bit lower than the 66M I think). Sooo.. getting that 100K will definitely put it equal to, to slightly better than the 66M. My comparison however doesn't take into account GOP1 in terms of motion rendering improvements, the absence of smearing, and the far cleaner noise that it has over a longer GOP which does improve image quality a lot on most shots (even if it is actually compressing at a higher ratio). Also, after all, the image quality at that 66M level is ample and definitely good enough for a lot of heavy post work.

    Edit : I will have another look at this tomorrow, really want to see how it holds up shadow detail in lowlight, which is the only concern I have about it. I do now after all have enough SD cards to use a GOP1 and it is definitely growing on me.
  • how are you guys capturing externally?
  • @nomad, of course :) And it may come to that, but I'm trying to travel light and not completely break myself financially!

    I have a free 2TB drive as well I could bring but it's not 'ruggedized' for travel - anyone have experience bringing a standard external on long trips versus 'optimized' drves? Maybe it's just hype.
  • We have dealers for external disks in Europe too ;-)
  • I'm getting about 24 minutes on a 32GB card although that's the camera's estimation, not the total running time after filling up 32 gigs.

    I'm really torn because I'm in love with how these images look, but it chews through so much disk space. I'm traveling Europe for the next month and I'm debating whether I should go all out with the 176M patch or dial it back to something more manageable like 44M. I'm bringing a blank 500GB external with me which would hold about 6 hours of footage @ 176M.
  • Stray,
    I agree, I'm amazed how stable driftwood's 176M GOP is!
    With avg bitrate hitting 150M, I bet Nick could tweak the i-frames up another 100K.
    If so, and stable like it is now, it's going to be freaking great!...

    Hopefully there's a Quantmemorebaby version coming our way! LOL
  • Nigel785,
    Since Stay's observation above about 176 running on extreme high detail around 150M, here's what you can expect per minute:

    150Mb/s = 18.75MB/s
    18.75MB/s x 60 seconds = ~1.125 GB per minute.

    Since this number is based on extreme continuous detail, I imagine you will do better than 1.1 GB per minute, but to play it safe. I'd say a 32GB SanDisk Extreme 30MB/s SDHC can offers 30 minutes safely.
  • get the 45mbit/s extreme not the 30mbit/s... and on a 8gb I get 5 mins
  • I may have to buy an extreme. How long we talking for recording time say at the Driftwood 176 gop1?
  • Long time reader, first time poster- feel compelled to add. I've been shooting (Driftwood's 176 GOP1 v3) for the past few days- and the word AMAZING falls short for how this footage looks in the edit suite & how far this camera has come! Watching these patches develop, something really special is going on with the 176. Thanks to everyone.
  • I've just spent some time with it and I've had no problems with the new sandisk extreme. http://personal-view.com/talks/discussion/comment/18767#Comment_18767

    I like it very much, but believe that due to the other settings its actually running at somewhere between 145-152M and not 176M. Has anyone else had higher rates from it ? Don't get me wrong, thats bloody good news as far as I'm concerned, it helps with stability. It does mean though that there is slightly more headroom to tweak up the image quality.
  • Yes, using Sandisk Extreme 30MB/s SDHC - no problem here using 176 GOP1 v3 uder extreme conditions (stray's new dense chart) as shown in my last post.
  • No problem here with 176 GOP1 Sandisk Extreme..
  • I second what @PerryWilson says.... I'm having 0 issues with SanDisk Extreme when using the GOP 1 176 M.
  • buy the Sandisk Extreme cards... im having 0 issues
  • @cosimo_bullo

    "though our freshly formatted Transcend 10 cards are having trouble keeping up with the data rate"
    Literally? Do you get errors or visual quirks in the stream?

    Is this the v3 (with the Q values) or the v2?
  • Good tests Perry. We're still getting the biggest and best looking files from the 176 file, though our freshly formatted Transcend 10 cards are having trouble keeping up with the data rate. Driftwood is a madman. Great stuff.
  • @proaudio4 @sohus Yes, my 88M AQ2 passes the dense deathchart. I'm convinced that the patch is okay, did a good series of shots with it today. I also shot with it at AQ3, and like bkmcwds first release of 66M GOP3 it does break the bitrate limit, but only slightly, under certain conditions. Out of the shots I took with it at AQ3 only one gave me a noticeable problem within a stream. See attached stream at frame 60, visually there is a noticeable jerk at that point. So.. my patch is fine as I posted it here at AQ2, just be aware that there could be problems with detailed shots at higher AQ.

    @bkmcwd Was thinking more about the 66M GOP3 and your requirements, being that you want a lower bitrate GOP3 for lowlight (or low detail). Well it does do that as you first released it, and you could make it even more sure that it'll behave and will not break the bitrate by using a soft lens too. However, I'd still use the driftwood 132M GOP3, the bitrate will be higher, but under the situations you want to use it for it won't be very high.
    88M GOP12 AQ3 odd drop.png
    1297 x 683 - 473K
  • GOP1 Intra 176M ver 3 'QuantMeBaby' settings (last driftwood's release) don't span.
  • @PerryWilson

    I-frames are intra coded frames, like a jpeg. In simply terms the smaller sizes are more compressed and hold less detail. Therefore, the larger the better, but of course at the expense of required bandwith, device read/write speed, and storage size.
  • Are we in the same page? There's no one settings for all. I like all settings :)
  • @Stonebat that's what I'm talking about I'm with you on that one 176 GOP1 v3 for the win..
  • GOP1 Intra 176M ver 3 'QuantMeBaby' with Quantizer 14 producing 800K sized I-frame? Impressive spec. Hopefully the next PTool improves the stability.

    How long can 16GB card record? 10 mins?

    For taking film, GOP1 all the way. For taking paid event, GOP3. For personal work, GOP12.
  • what is I-Frame size and what is the up side to having larger I-Frames... man I hope driftwoods shoot is going good, and excited for him to get back at it... all we need is a good movie profile a good flat S-log profile
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