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GoPro Hero3 , 4K is here in Baby Steps for $399.99!
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  • @trevmar "After running through GoPro Cineform Studio the metadata is retained in the 10-bit dynamic range 4:2:2 clip. That allows you to change white balance, brightness, saturation, etc, in a non-destructive manner. Which is what Cineform Studio does, before it exports to MP4 again. Cineform is a wonderful workflow, and has saved me a lot of grief over the years.

    When you play with the MP4 files the dynamic range available is only 8 bits. This makes it tough to maintain gradation in the shadows and highlights."

    Thanks for the info! I don't really understand the 4:2:2 stuff but basically I should just convert with cineform (without any color correction changes) and then color correct in premiere or whichever NLE I want? I originally tried the cineform color correction and sharpness/contrast and the video came out way too red in some areas while others were perfect (was going for cinema feel). I like how in premiere it breaks down color correction by shadows, midtones, and highlights.

    edit I'm not home currently but if I remembered correctly cineform can let you export in avi and mp4. Which should I want or is that irrelevant as long as it has converted it.

    edit2 Looks like I found some more info here and basically reinforces what trevmar has been saying. http://gopro.com/wp-content/uploads/2012/02/GoPro-CineForm-Studio-Manual-01.pdf

    The interesting tidbit I found is any edits I make on cineform immediately shows up in NLE without having to reimport the source file.

  • @trevmar: I don't get it. All GoPros record using the h.264 codec which is 8-bit 4:2:0.

    So how does a 10 bit 4:2:2 workflow give you more dynamic range if the source is only 8-bit?

  • @Zakk

    +1 inquiring minds want to know.

  • @Zakk @ mpgxsvcd As I understand it, the gamma is turned into a log curve in the camera, so that a wider range of video levels can be truncated down to fit in the 3x8 bit MP4 container. GoPro Cineform Studio then expands these to the 10 bit range, although there will obviously only be 256 discrete levels across that 10 bit range. That is not so unusual, when watching the RGB parade levels on my Sony Vegas I frequently see quantization steps in the videos from cameras, especially near black. Actually, I was just looking at a Protune clip, and it seemed pretty continuous to me, with levels smooth from 0 to 255. When I run Cineform Studio in the background while I am editing the clip in Vegas, changes made to the white balance, etc, in CS appear immediately on my Sony Vegas timeline. Pretty interesting... But I am concerned what happens when I archive the masters away for a time when CS no longer exists...

    Oh -when I render from the Vegas timeline, it seems I can use Cineform as the output codec, as long as Cineform Studio is installed and I don't output resolutions above 1920x1080. I have complained to Cineform Tech Support that they need to allow me to support 2K7, even if they reserve 4K for the bigger-pocketed pros...

  • Essentially a larger dynamic range is "compressed" into the h.264 file. When you process it in Cineform Studio it applies the Protune curve, which decompresses or expands the dynamic range closer to the original of the scene. For technical details, David Newman explains it fully here, math included: http://cineform.blogspot.ca/ See the second post, Wednesday, October 10, 2012 Protune. Hopefully it will make more sense!

  • Here is a shot of the RGB parade from my Vegas from a typical 1080p_24T cineform-converted clip. Note the discrete quantization levels. I haven't counted them, but there are a few gaps, and I suspect there are fewer than 256 here... But there are enough to give smooth color...

    Protune_Parade.jpg
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  • I don't know much technical detail on the dynamic range but I went back and used cineform to process before I edited in premiere pro and I will say this:

    1) Didn't notice much difference in color saturation 2) There is a big big difference in the sharpness and contrast.

  • @obnoxious2 I don't know whether it is relevant in your situation with premiere pro, but my sony vegas uses cineform as a native format, and will show HD previews in real time in this format (despite the high bit rate). I do recall seeing an option under the "C" which pops up in the status bar while Cineform is running which claims to speed full-screen playback. I don't have any problems with speed, but I thought you might be interested in knowing the switch is there :)

    The only downside to Cineform is the high data rate and consequent huge files. But it loses nothing from generation to generation, previews in real time, and IMO is the ideal editing format.

  • Looks like the GP3 can be matched reasonably well to a 5D MKII when using the right settings

  • I can't believe they actually delivered GP3 black to my door!!!

    One question. Is it safe to use iPhone USB charger on GP3?

  • I have used a variety of chargers, including the 1 inch cube iPhone charger, on my GoPro. I see no reason why it would be sensitive to charger, and I have seen no problems either.

  • Thanks. I'm charging it.

  • I tested the audio inputs using my GoPro 3 microphone input cable (which arrived today). I had previously tried to make my own cable, and failed :-(

    There is a DC level of 4V on each mic input, which will drive the average electret insert very well. I shorted the unused mic input and applied an ultra-low distortion sinewave generator to the other. The spectral graphs which resulted are shown below for 2mV, 20mV and 150mV RMS inputs respectively.

    There is clearly Automatic Gain Control being applied to the input, with a compression level giving plenty of pumping headroom, at about -25dB0. The channel separation is about 40dB, but there is significant change in the second channel noise level, there should not be any. Harmonic distortion is low enough, but clearly there are audible effects in the noise level. I would like to check the IM distortion, but was too busy today. The AGC comes in just above 2mV RMS input level.

    These are not HiFi inputs by any stretch of the imagination. I will plug my Rode's into a real audio recorder, and sync the files in post...

    2mVrms_short.jpg
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    20mVrms_noshort.jpg
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    150mVrms_short.jpg
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  • I was surprised that the device itself can't playback. But the upcoming smartphone app will be able to playback. Any date for the app release?

  • @Stonebat

    Sorry I was wrong it is 12/14/2012(Friday) instead.

    http://gopro.com/software-app/gopro-app

  • This week is still good. It's amazing that people have been using GoPro units without preview feature.

  • Wish me luck!

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  • DIY 3d case?

  • @stonebat Yup! Made from a couple of macro sliders and misc hardware. :3 Stripped the rubber grip from the bottom one, so the GPs can parallel align to the left over groove. Found that just tossing 2 on one slider with the tripod mounts was a headache, so I ditched the cases completely. Hopefully GoPro improved their tolerances for lens mounting on the new cams.

    There's also enough room for all power and video cables on both, and can push the cams out to the sides for shooting distant objects. If I can figure out how to make the right kind of mounts, I can also set them up like the original 3D housing, too, though that's not on my list of priorities. At the moment, the they're a little further than intraocular distance, but that's fine for now.

    Testing for the next 2 days, since the weather's finally clearing up around here. If all goes well, I'll be shooting a drifting event on Sat! :)

  • Does anyone know if the update has been posted that enables the GP3 Black Edition to connect to the app? I haven't seen it, yet.

  • Yup, it's out. New firmware 1.1.13, but doesn't seem like the app has/needs an update.

  • My app updated last night around midnight. Now I just need a Hero3 to go with it! :)

  • I downloaded the new Hero3 firmware, still the same version number, but different file sizes. Installed them on the camera. Installed the android app (as of 7:30am PST). the Cineform studio version is still 69, which doesn't recognize Hero3. So I figured out the default WiFi password was "goprohero" and connected the app to the Hero3. The preview lags about 3-5 seconds, and is the same size as my Touch LCD (which has no lag). The app will not show 2K7 or 4K previews at all, and the setup screen is clearly not yet compatible with the Hero3. But at least the app "record" button works OK, as does Power on/off. Still, I can do that with my remote LOLOL.

    I guess the next step is waiting for the android app update. But all-in-all I am under-awed at this point :)