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  • #31
    Yeah, so more experimentation leads me to this conclusion...

    With the HD1400 connected, and running in 60Hz mode (which is the correct setting) I can't get any video from it - the only 60Hz mode is the 'Constant Rate' one which doesn't seem to get any video at all.

    However I can get pictures of it if I run the deck in 59.94 mode, however as the tape is (and has to be) recorded at 60Hz, I don't know what the effect of this will be. On the short (30-60 second) clips I've grabbed at the moment, it seems alright, but the reported framerate in the AVI export I've made is 24.9fps, which is a little worrying.

    I probably need some clarification on the actual implications of capturing 60Hz material in 59.94Hz. And I need to conduct some further and more detailed test.

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    • #32
      Let me try again.

      The Edius 50 and 60 hz setting are diferent of the processing options you have in the varicam.

      The Edius setting in the and 60 hz headers are to make a distiction for NTSC AND PAL.

      That is why you don't have a 960x720 25p over 60p under 60 hz header

      960x720 25p over 60p need a pal profile.
      If you are correct that the that is what the footage was shot at.
      Rember I am not talking about the processing options in the varicam.

      Can you recheck the footage information so we can try to help you.

      SR
      Steve
      EDIUS Trainer, Grass Cutter Gold
      A proud EDIUS EDITOR
      For more information on the Grass Cutter program please visit: http://www.grass-cutters.net

      Comment


      • #33
        960x720 25p over 60p is indeed the profile I've used, found in the 50Hz section (from memory, I am at home now).

        The Input settings I'm seeing now are the same as in KH's initial screenshot.

        I have 720/59.94p
        720 Constant over 60p
        720 Constant over 59.94p

        The footage has been shot on Varicam as 25fps, with 60Hz frequency.

        With the AJ-HD1400 operating in 60Hz, I cannot capture with any of the three input settings mentioned above (although I can control the deck).

        If I switch the deck to 59.94Hz (which seems to work, but isn't 'correct' given the tapes originating frequency) I can capture footage with the 720/59.94 setting. However neither constant rate setting gives me anything.

        So far, the 59.94Hz option there seems to work, however I am not totally sure about what the overall affect will be of operating the deck out of frequency like that, hopefully Rick, or one of his colleagues from Panasonic will be able to clarify that for me.

        What I can say so far, however is that capturing in Edius and exporting (through ProCoder) to Avid seems to introduce no significant image degradation. However I still have quite a bit of testing to do in that area before I can say what the best process will be. At this stage, however, I am fairly confident that our post production workflow is probably going to involve Edius as an ingest tool (although I am well aware it is capable of much much more) - assuming that no harm is going to come of my footage by digitising 0.6Hz slower.

        I applaud, very strongly, GV/Canopus in managing to implement this Firewire native capture that seems to so elude the bigger players (namely Avid and Apple). And I will, in time, delve further into Edius as a whole NLE.

        Hopefully I will be shooting full camera tests later this week, and testing workflow more completely. So, to be continued...

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        • #34
          Dylan,

          This is what I have found once I unscrambled our 1400 from the effects of numerous users.

          You are quite right, if the deck is set to 60Hz as the reference then Edius cannot see the incoming Firewire signal. If it is changed to 59.94Hz the it works perfectly in 720/59.94 and Constant Rate Shooting 720/59.94 and Constant Rate Shooting 720/60.

          If I capture the identical sequence in each mode, I found that the latter two (constant rate) when overlaid in the Edius timeline are frame for frame identical. However the 720/59.94 seems to lose a frame somewhere along the line. I cannot be exactly sure about this as the clip is only 35secs long so not really enough to tell.

          The project is set to 50Hz 960x720p 25p over 60Hz.

          When I get a chance I will do some more testing with longer duration clips. I have also asked Panasonic in Japan if they can shed any light on this.

          Rick

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          • #35
            50HZ 960X720 25p OVER 60HZ there is no such setting in EDIUS.

            There is a 50 hz 960x720 over 60P

            You guys seem to confuse that alot

            It makes me think that maybe the source format is also confused .

            hertz and progressive are different things
            Last edited by SRsupport; 10-16-2007, 12:21 AM.
            Steve
            EDIUS Trainer, Grass Cutter Gold
            A proud EDIUS EDITOR
            For more information on the Grass Cutter program please visit: http://www.grass-cutters.net

            Comment


            • #36
              Sorry, my mistake someone interrupted me in the middle of the post and I mistakenly typed 60Hz instead of 60p.

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              • #37
                But the other problem is that you are using an ntsc profile to capture pal recorded footage.

                50 hz 960x720 over 60P yields a frame rate of 25 progressive

                60 hz 960x720 59.94p yields a frame rate of 59.94 progressive which is far from your original footage . Mostly used for countries using natively ntsc




                Steve
                EDIUS Trainer, Grass Cutter Gold
                A proud EDIUS EDITOR
                For more information on the Grass Cutter program please visit: http://www.grass-cutters.net

                Comment


                • #38
                  Neither myself, nor Ricksta (I don't think) are using NTSC-rate profiles.

                  The Preset setting I've been testing with is:
                  Generic OHCI HD 50Hz 960x720 25p over 60p

                  Indeed, I've just tried what Rick mentioned, and with the deck in 59.94Hz operating frequency, I can capture with all three 720p 59/60 input settings. This is technically wrong however, as the tape has been recorded at 60Hz. But like I said before, until Rick hears from the big geeks at Panasonic about this, I don't know what the real outcome of that difference in frequency is.

                  I've also tried a 50p over 60p project setting (as 720p50 is what I will be editing with in Avid) - but, predictably, this works but gives me double-speed footage. Which, while amusing, isn't a lot of help for me :)

                  A large part of the problem I'm facing here is to do with the Varicam format. It will record any framerate from 1-60fps. It has to operate and a system-frequency of 59.94Hz or 60Hz. That is what Rick and I are referring to. The limitation I face is that the Varicam format is not widely supported for PAL-based rates (25/50) as it requires communication with a deck operating in an NTSC-based system frequency (either 60Hz or 59.94Hz). This difference (between project/timeline framerates, and deck operating frequencies) is enough to ensure that IEEE1394/Firewire/OHCI capture is not possible in these modes in Final Cut Pro, Avid (any version) or any other NLE I have found.

                  We realise that the framerate and frequency we're working in has to be 50-based, and we're not making any mistakes in that respect.

                  So far Edius is the only NLE on the market, that I have been able to find, that supports Firewire capture from 60Hz DVCPro HD material in a 50Hz based framerate.
                  Last edited by Sycophant; 10-16-2007, 02:53 AM. Reason: More detail

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                  • #39
                    Originally posted by Sycophant View Post
                    Neither myself, nor Ricksta (I don't think) are using NTSC-rate profiles.
                    I've also tried a 50p over 60p project setting (as 720p50 is what I will be editing with in Avid) - but, predictably, this works but gives me double-speed footage. Which, while amusing, isn't a lot of help for me :)
                    When you have captured the file in that project select a clip in the bin press alt+enter go to video info and tell me what the framerate is .
                    Steve
                    EDIUS Trainer, Grass Cutter Gold
                    A proud EDIUS EDITOR
                    For more information on the Grass Cutter program please visit: http://www.grass-cutters.net

                    Comment


                    • #40
                      Varicam essentially runs the camera "overcranked" all the time, so the are more samples than the target shooting rate. The extra samples can then be used for slo-mo, or simply the change the playback rate.

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                      • #41
                        Not quite. It only records the target framerate, but spreads it over 60 frames.

                        So if shooting 25fps, only 25 of the 60 frames have a unique images. ie, you can get more out of it than you recorded in.

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                        • #42
                          Hmm, seems my understanding is flawed then.

                          So if only 25 out of the 60 images are unique, isn't it just a waste of space?

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                          • #43
                            Well, yes. Sort of. I'm not sure about the rationale, but basically I believe that it's hugely difficult to run tape at a non-constant speed.

                            The Varicam records 60 frames, and of those 60 frames anywhere from 1-60 can be 'active'. Other frames are duplicates of those active frames. In capturing the footage the NLE simply takes the frames that are tagged as active.

                            It is possible, somehow, to shoot a constantly higher framerate (say 50fps for PAL rates, and 60 for NTSC rates) then you can pull a different (evenly divisible) rate from it.

                            The problem would be, if the camera always recorded 60fps, that it would be impossible to get any framerate that wasn't evenly divisible by 60 as smooth motion. So getting 30 or 15 is easy, just take every 2nd, or 4th frame. But to get 25 out of that wouldn't work.

                            Sony has just launched their XDCAM EX camera, which also offers variable rate shooting. Not sure what it does, but I believe it's a similar thing.

                            The RED camera is different however, as it's basically just shooting an image sequence - it's like film.

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                            • #44
                              Originally posted by SRsupport View Post
                              When you have captured the file in that project select a clip in the bin press alt+enter go to video info and tell me what the framerate is .
                              In a 50p over 60p project, when I capture footage shot 25p over 60 with the 'Constant Rate' capture profile I get a clip in the bin that is 50fps, but that plays at doubletime - which is what I'd expect.

                              I can change the framerate in the properties to 50fps, and it plays at the correct rate, but I'm not happy with the way to refactors the timing in that mode. It seems to create interpolated frames to fill the gaps, which provide an unusual appearance that I don't really like.

                              At present if I capture into 25p over 60p project, then import the resulting 25p footage into Avid, Avid doubles up the frames to produce 50fps material.

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                              • #45
                                True, it's insanely difficult to run magnetic tape as a non-constant speed. Too much mechanics involved to get it reliable and affordable.

                                Ahh, okay, I figured out my confusion...

                                The variable frame rate function is supposed to allow for blur/slow effects, but even the operating instructions don't really tell you what to do with it after it's on tape. Weird.

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