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frost

GoPro HD for 3D images

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are you talking shutterspeed or frame rate? Very different animals. Framerate is constant. Shutterspeed is variable.
Shutterspeed is gonna be what it is with a GoPro, you can't lock it. Shutterspeeds will be close enough that it's not an issue, and unsynced shutters are a VERY small issue when dealing with speeds of 1/48, 1/50, or faster. (see attached).

Framerate...easy to lock a sync pulse and be spot-locked on (no pun intended).
The sound may -carry- over 2-3 frames, but the attack/transient point + amplitude is only a sample. (see attached)
Depending on the application you're using, be sure frame quantization is turned off. (some apps can't do this).
If you can line up the attack/transient points to within 1/250 of a second, there is NO WAY the eye nor ear can detect the offset.
In the example I just created for you, the transient points are within 1/1000.

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is that you with the mullet?
nice hehe

I guess I am talking about frame rate, shutterspeed hasn't really come into my thinking, I am guessing that if I a shooting at 60fps then shutter speed is going to be very fast. Does a gopro slow the shutter speed in low light? if so then both cameras are pointing the same way to they should adjust pretty much the same. I dont think I am too worried about shutter speed.

my workflow is basically that I line up the two streams using an audio click (like you have said) and then fine tune them with a visual cue, because in my experience they are coming a couple of frames out and while it looks 'okay' it looks a whole lot better if i spend a couple of minutes doing it properly

I'm definately not a pro at this but I am getting good results, although as I said a bit pointless really

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Nah, I'm the dumbass in the picture that doesn't know the difference between framerate and shutterspeed. (or what a mullet actually is).

If you're shooting at 60fps, then the shutterspeed could be as slow as one exposure every 1 second, every 5 seconds, or every 1/8000 of a second and every value in between. Frames per second bears zero relationship to shutterspeed. Your car can be turning a constant 3,000 RPM but the speed may vary depending on terrain, gear ratio, number of cylinders, etc.

[edit] attached is an image where I've offset sync pulses on three separate cams. The eye, nor the ear can detect the offset even though they're 50ms off for a total of 100ms offset in cumulative time.

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Roger that. :P

I guess you are looking at it from knowing all the technically wizardry stuff and I am looking at it from a 'monkey see' kinda place. My point is basically that with close up fast moving action on a go pro (with its wide angle lense) something like the near arm of the handicam driver, moves a lot and real fast and so being one frame out actually stops the illusion from working 100%. Its a fairly minor thing, but I have found it is the difference between people going 'oh it kinda works' and 'f^%k... thats quite cool'.

If the streams are a frame or two out then it is particularly noticeable on exit especially if there are a couple of somersaults.

Its been fun playing with some of the different features on vegas, not as much fun as being in vegas however :)

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the point is, there is _no reason_ to be a "frame or two out." None.
Even the most simple app in the world will allow for frame accurate sync.
If you were shooting really slow shutterspeeds (which the GoPro doesn't do), then the shutterspeed would be a real problem, but shooting at high shutterspeeds...being in perfect sync would be nirvana, but it's not at all a big issue.

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Interesting that they invert one of the cameras to get the lenses as close together as possible. I thought you needed a bit of space between the lenses for the 3D effect to work. Is it because the lenses are so wide and physically small that they are placed so close together?

Edit: so rereading this thread I see the images where the mount has both camels in the same orientation but watching the video the mount definitely has one rotated 180 degrees. I also notice the video is a month older so I assume this is the standard way now.
Skydiving Fatalities - Cease not to learn 'til thou cease to live

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http://gopro.com/hd-hero-accessories/3d-hero-system/

Quote

The 3D HERO System allows you to combine two 1080p HD HERO cameras into a single housing to record 3D video and photos while simultaneously recording in 2D. A synchronization cable plugs into the rear HERO Port on both cameras to join them together, enabling both cameras to record video and photos in perfect synchronization. This is a requirement for professional quality 3D and is available only from GoPro.

The included 3D editing software—GoPro Cineform Studio—makes it easy to convert your 3D HERO System footage into viewable 3D files you can watch on your computer, online at sites like YouTube, and on your 2D or 3DTV at home

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The close spacing is due to the extreme wide-angle.
The examples Ive seen so far from the GoPro 3D setup vary from 'nice' to 'mwaa'. The 3D looks okay around the center of the image, though not a lot of depth beyond all the close range stuff. And the image seems to loose allignment around the edges quite visably.

Using properly alligned seperate cameras, or the consumer type JVC/Sony 3D setup, the results look a lot better. Especially when you have a lot of distance/depth in the scene you're shooting, a seperate setup for which you can adjust the allignment/focal point (be it 'locked' during the jump itself) is definately still the best result.
JC
FlyLikeBrick
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The example I saw also had some minor sync issues. Though they where timed properly in terms of synch start, they seemed to differ about a milisecond, and on fast moving, close range stuff definitely showed some weird strobing due to the left/right eye seeing different things..
JC
FlyLikeBrick
I'm an Athlete?

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They also posted a highlight reel on YouTube. This one seems to look quite okay, though does show the image often falls 'flat' when the subjects are more than 10 to 20 ft away from the camera. Loosing the whole depth illusion. But of course the highlight reel only focuses on the close range/awesome shots.

http://www.youtube.com/watch?v=CDQ3rmEeKN8

I guess thats the trade-of for the extreme wideangle they use. Needing to mount the cameras this close to keep the images alligned.
With a lesser wide-angle, you can space the cameras further (eye distance gives you a depth perception of up to 40 ft or so. Going wide for large vistas or bigway stuff is also possible). Depending on what you want to shoot in 3D (close or far) it may be an easy solution, or one thats not really gonna suit your needs.
JC
FlyLikeBrick
I'm an Athlete?

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Didn't take long for the Cineform word to get out, did it!?
Folks will love the Cineform compression, and it spells some good futures for GoPro. GoPro is next to the VASST booth at NAB this week, so I'll see what info I can drag out of them. We've been users of Cineform for years; it's one of the best compressions available. In 3D, this is critical; keeping a good image while keeping file size down.

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