Personal View site logo
2K BlackMagic Pocket Cinema Camera, active m43, $995
  • 4493 Replies sorted by
  • Thanks for the follow up!

  • @DocoDocoMan I've been working the bitrate numbers for BMPCC RAW and this is what I came up with based on avail info... According to BlackMagic, 2.5K RAW averages 5 MB per frame. At the reduced resolution of 1920 x 1080 we can expect to see an average of approx. 3.14 MB per frame. At 24fps uncompressed, that is a data rate of 75.36 MB/sec or 94.2 MB/sec for 30P. With 1.5:1 compression that is 50.24 MB/sec at 24P and 62.8 MB/sec at 30P. At 2.2:1 compression they should actually be able to comfortably record RAW to 45 MB/sec cards at all frame rates. It's unlikely they will offer compression rates that high (unless the encoder is robust), so most likely we can expect 95MB/sec cards will be necessary. So UHS-II cards would likely be overkill for the needs of this camera.

  • @Tron If they could get the compression that high, it'd be great. That would only be a smidge higher than the 27.5MB needed for ProRes, but like you said, most likely going to be a 1.5:1

  • RAW compression on a RED yields pretty good quality at 8:1, but it's a wavelet and applied before de-bayering (which inflates data). Anybody knows if DNG is before or after de-bayering?

  • @kevin_kirchman I also ran the numbers for converting DNG RAW to Cineform RAW and the resulting data rate runs somewhere around 100Mbps. That's pretty amazing considering that's just twice what the GH3 records at, and you still retain the benefits of RAW... it would be a great archive and intermediate codec to work with.

  • @nomad, RED raw is 'lossy' (data is thrown out), that's how they can achieve such high compression ratios.

    Pocket is supposed to be lossless compressed initially (with a lossy mode to follow later). With lossless compression no data is lost, it's 100% identical to the uncompressed data (like .zip files). For AV data you tend to get around 1.5:1. However it depends on the data, an almost black frame will compress much better, tons of tiny detail = worse. BMD have to allow for the worst ratio scenario when spec'ing compatible SD cards.

    @tron yeah those are the numbers I originally came up with too.

  • @nomad

    I'd never go less than 6:1, and that's for web stuff. Like @_gl said, RED RAW is a lossy compression, and the CinemaDNG RAW is supposed to be lossless.

  • As I understand it, CinemaDNG also has a visually lossless (lossy) spec that will be implemented on the 4K cam, so it's not just a lossless spec.

  • @tron yep, as I said:

    "Pocket is supposed to be lossless compressed initially (with a lossy mode to follow later)."

  • If the RAW footage is at 100 MB/sec then how is even a 95 MB/sec card going to work?

  • Everyone just needs to wait for an official SD list otherwise you might be kicking yourself.

  • @mpgxsvcd you obviously didn't read through or failed to note Mb vs. MB

  • @Tron I'm going out on a limb and say that mpgxsvcd knows the difference between Mb vs. MB ;)

  • 95MB/s is also the peak read speed of the card, not the continuous write speed.

  • facepalm the same way Intravenus 139Mb/s footage records to them just fine - magic

  • Is anyone going to the LA event tomorrow? It would be great if you could take down some of our questions and get some answers. Anyone? Anyone?

  • @shian....yeah, I've just bitten my tongue on this whole thing. Between this thread and the development topic thread, it doesn't seem like anyone back reads or researches a damn thing before they post. Simply amazing.

  • @vicharris Hey guyz, I heard that the BMPCC might use active mount MFT lenses, is this true? :-)

  • @ahbleza What's this BMPCC you're talking about? :)

  • Yeah, I heard it could like shoot very fresh films. Like sushi or something!

  • @chaos123x I might have to... it's practically across the street from me.

  • @ahbleza...yeah, also anyone know how the 12-35 lens will work on the BMPCC? I just wish someone would show us footage and if the auto focus works. Also let's talk about rigging this thing up to look like a Varicam, that should be fun!!!

  • I'm recording 5DMKIII Magic Lantern uncompressed 14 bit 1080HD RAWs at around 94MB/s (not Mb/s) constant speed on a Lexar CF x1000 card, even the best SD cards in its other slot get nowhere near this write speed stopping writes after around 4-5 seconds. However, with 12 bit in on the pocket cam and a compression method based on 'zip theory' lossless cinemaDNG RAW, its likely they will be able to deliver constant recordings - at what cost I don't know. I'm so dying to analyse the pocket cam.

  • @shian Please go peep it man!!!!

    ---Anyways... on lenses...I am pretty sure the infamous"market footage" John Brawley shot is on the 12-35mm but It was pre-autofocus.... also I saw a video "review:" with the 7-14mm attached and the camera turned on... Lens was at 7mm and from what I could gleem from the rear screen on the BMPCC it look pretty good on there. Wide non-distorted... Too bad that lens wont take filters :(... but I suppose I have a matte box for reasons beyond making my camera rig look cool- lol now if only I could afford a better filter than the crummy Lee ND I have...