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GH2 Flow Motion v2 - 100Mbps Fast Action Performance & Reliability for Class 10 SD cards
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  • LPowellLPowell

    @GH2_fan - You must have inexplicably missed the following presentation, which was included in your standardized training packet (Figure 1. Flowchart of the Driftwood Countermeasures):

    http://www.sabo-int.org/guideline/pdf/driftwoodCountermeasureGuideline.pdf

  • rigsrigs

    (Figure 1. Flowchart of the Driftwood Countermeasures): Lee- Thanks for the laugh

  • LPowellLPowell

    Direct quote from the training manual:

    The basic point for driftwood planning is the position at which the driftwood quantity to be handled in the driftwood countermeasure plan is determined. The basic point for the driftwood countermeasure plan is placed upstream of the target protection area.

  • valpopandovalpopando

    @LPowell Hi Mate , Your patch sounds very nice ! LOL http://www.flowmotion.net/

  • driftwooddriftwood

    LOL @LPowell

  • Lanz1Lanz1

    @duartix as I wrote, it's 1080P 25fps, not deinterlaced ;) you can see from my grab screens that I was playing the original MTS files al 100% resolution

  • duartixduartix

    @Lanz1 I fell into that trap some time ago: http://www.personal-view.com/talks/discussion/comment/57716#Comment_57716 It was a field issue and I found out how to properly import PsF video here: http://www.personal-view.com/talks/discussion/comment/57925#Comment_57925

  • LPowellLPowell

    @duartix Yes, as I explained to @karl on page 7 of this thread, whenever HBR (or any psF video) is imported into a video editor, you must manually insure that the footage is interpreted as progressive.

    The GH2 records progressive HBR videos in exactly the same 1080i file format as interlaced FSH files, and there is no explicit way for an editing program to tell the difference. As a result, editors such as After Effects naturally assume that HBR files are interlaced, and interpret the footage as "Upper Field First", which causes spurious interlace artifacts. To correct this, you must use AE's Interpret Footage dialog to set Separate Fields to OFF. That will eliminate spurious interlace distortion in HBR footage.

  • LongJohnSilverLongJohnSilver

    @ lpowell

    "When shooting in 80% Slow-Motion 24H mode, the video is actually being recorded at 30p, but the MTS file is marked to play back at 24p. To make it play at its native 30p rate, no speed up is necessary, however, you must use a video editor to reinterpret the frame rate as 30p."

    Sorry I see this only now. Yes I mad a mistake. BTW When shooting in VMM 80% is the real framerate 23.97 as usual 24p cinema mode? and conforming to 30p is the real framerate 29.97 also for VMM 80%? Right?

    Thanks

  • LPowellLPowell

    @LongJohnSilver No, you've got it backward. In VMM 80% Slow-Motion mode, the camera records at 29.97fps in "24H" mode (or 24L if selected). The only thing that makes the video slow-motion is that the metadata tag in the MTS file misrepresents the frame rate as 23.976p. When you play back the file, the video editor or player reads the metadata tag and plays the video back at 23.976 fps. To play it back at its original 29.97fps, you have to manually instruct the editor or player to interpret (i.e. conform) the footage as 29.97p.

  • jrdjrd

    Surely somebody is editing native Flowmotion 2 24p footage and can comment on time-line responsiveness? Ideally, compared to one Driftwood's intra-frame settings, but any information at all(?)

    Previously asked, no responses.

  • LongJohnSilverLongJohnSilver

    @LPowell ok thanks. I use Edius, I got it just editing the file properties :)

  • LongJohnSilverLongJohnSilver

    @lpowell

    here again with a problematic clip. :( it seems that water is the worst enemy of our beloved camera...

    I uploaded to vimeo a clip from yesterday session. It's shot using VMM 24p 80%. On some shots the bubbling water moves in a completely unnatural/artificial way. It's like having subtle artifacts and the water moves like under a strobe light. I tried playing this clip with VLC, WMP and importing it in Edius. Actually once I conform it to 30p problems are further enhanced.

    Maybe it's me or my pc. Please give me your opinion on the original mts file. Vimeo is terrible converting mts files.

    PS I came back to the same place where I got completely useless shots on Sedna 30p. I'm starting to believe it's the place...

    Thank you in advance

  • LPowellLPowell

    @LongJohnSilver All I can see is the embedded video, and I can't really spot the issue. Can you make the original MTS file available for download on your Vimeo page?

  • LongJohnSilverLongJohnSilver

    @Lpowell sorry. Vimeo is starting to pissing me with their options. It doesn't have the unlisted video option.

    It should be ok now.

    Thank you indeed

  • sam_sticklandsam_stickland

    @jrd I haven't tested with FlowMotion2 but when I did my last round of tests back in February I found that I had considerably less timeline responsiveness with FlowMotion compared to Cake and Sanity (using PPro 5.5). It was enough on a problem that I went with Cake for the event I was filming.

    I didn't have time to fully diagnose the problem and I haven't tried with FM2. YMMV. I didn't report this at the time because I didn't feel I'd investigated it enough.

  • LongJohnSilverLongJohnSilver

    @jrd @sam_stickland I did not notice any difference among various settings on the timeline. I'm using Edius 6 which is incredibly fast and responsive working with AVCHD files on the timeline.

    Best

  • sam_sticklandsam_stickland

    I'll retest with FM2 this week. I've been meaning to give it a go anyway :)

  • LPowellLPowell

    @LongJohnSilver Thanks for making the video available. You've found one of the most challenging types of subject matter for an AVCHD encoder - a combination of high-detail foliage beneath a sheer, nearly transparent water surface. If the water were more turbulent, it would obscure the details of the ferns and reduce the required bitrate. But with just a bit of surface shimmer, the foliage details are refracted in myriads of subtle specular highlights that the encoder must track as individual variations in frame-to-frame details.

    With this much detail in VMM 80% Slow-Motion, FM2 is working in turbo mode at 140Mbps peak, and you've hit the limit of what the encoder can handle with that amount of bitrate. I'd recommend either widening your aperture (to lower the bitrate on distant details in the upper part of the frame), or switching to standard 24H mode, which requires 20% less bandwidth than 80% Slow-Motion mode.

  • LongJohnSilverLongJohnSilver

    Hi Lee,

    thank you for checking my shot. I see your point. On your FM samples the river bottom was of nude rocks and the water was flowing much faster.

    Are you shure it's a problem of bitrate? On stream parser I see 119 Mbps (I'm a noob) but I uploaded another shot where the water is only in the lower partof the frame (about 88Mbps) and still the gentle water circles are rendered in a artificial way. Could it be a weak point of the encoder? Does it mean that with the current GH2 these kind of shots cannot be made? Am I the only one filming nature subjects like these?

    The problem shooting in 24p above water and 30p underwater is mixing the clips on the timeline...

    I would be curious to see an unhacked GH2 on this subject or another canon camera :)

    Thanks a lot

    PS

    After the bush of death now we have the lake of death :)

    Here it is: the water is still frying....

  • mo7iesmo7ies

    @LongJohnSilver, do you get the same problem while shooting this scene in 24H mode, or not?

  • LongJohnSilverLongJohnSilver

    @mo7ies

    I don't know I was there for real shooting not for testing. It's the second time I fail...

  • LPowellLPowell

    @LongJohnSilver Yes, with this much variation in frame-to-frame detail, bitrate is the limiting factor. The unhacked AVCHD encoder will simply smear the details or plunge into Fallback Mode. I uploaded an example of this syndrome in the fourth post in the first page of this thread.

  • cbrandincbrandin

    I've always wondered whether this water rendering problem is inherent to water or because water is nearly always toward the bottom of the frame. Sometimes the encoder mis-estimates the base Q value to encode busy scenes. What happens is that there ends up being a lot of "skipped" macroblocks toward the bottom of frames because the encoder has run out of bandwidth.

    An interesting test would be to record the same subject with the camera upside down. This would tell us whether the codec is failing because the scene is too busy, or whether it fails because water is typically lower contrast than grass or trees and the codec "sacrifices" lower contrast detail in favor of higher contrast detail.

  • LPowellLPowell

    @cbrandin Yes, I've examined videos where the encoder appears to underestimate the bitrate needed to complete each frame. With Elecard Streameye, you can see where the QP level for individual macroblocks becomes noticeably coarser toward the bottom of the frame. When this occurs, the QP range may also increase dramatically. From what I've seen this tends to happen more often in patches that fix the bitrate at a nearly constant level, mimicking the behavior of a CBR encoder.

    I checked out the video uploaded above by @LongJohnSilver and found that it does maintain consistent QP levels from top to bottom of each frame, with no skipped macroblocks. In all cases I've been able to test, Flow Motion v2 has not suffered from this syndrome.

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