Canon 3D?

[Sareesh Sudhakaran]

Is it possible to shoot 3D or create a rig with the Canon 5D/7D/Rebel 2Ti? Are there any custom made rigs for the same? If so, can we change the lenses on these cameras - do they use beam splitter or side-by-side, etc?

The opportunity is fantastic - to shoot full HD with a light-weight system. That's one big dream coming true.

[Adam Stanislav]

Aren't the bodies of the Rebels too wide? I do not have a digital Rebel, but my film Rebel is 14 cm wide, more than double the span of human eyes. Though, I suppose if you mounted one of them upside down, you might be able to get the lenses close enough for 3D.

The tricky part would be to get both cameras focused the same.

[Alister Chapman]

You could use a beam splitter to get the interaxial down, but there is no way to accurately sync the cameras that I know of.

[Ryan Farnes]

Syndicate - Canon 7D BNC-R Cine HD.

Scroll down a bit and behold the magic. Preliminary, but promising. They even have some red/cyan 1080p and 720p clips of just shooting on a street.

I was pretty impressed.

[Adam Stanislav]

Looks like they did just what I suggested and mounted one of them upside down.

[Sareesh Sudhakaran]

But the syndicate one doesn't allow for locking the two cameras. Don't they shoot H.264? If that's the case, how do they guarantee the same frames are being shot? What about syncing the shutters?

Also, we can't control convergence or change the distance to less than 12cm. We can't achieve the 65mm distance. ET does have a 5D (should work for 7D) beam splitter rig that looks more robust.

[Ryan Farnes]

I have no idea how accurate their "rig" is for professional stereo production. Just had been at their site recently and thought I'd pass it along. The sample videos they have did seem pretty cool as far as just being a test. If you've got red/cyan glasses, check them out.

I wonder if they've taken their 3D rig ideas any further.

[Adam Stanislav]

They do say "Then next step is a mirror solution covering 0-120 mm eye distance."

As for syncing, they seem to be using the nanoFlash. You can sync two nanoFlashes, so maybe that is how they do it.

[Bruce Schultz]

I've been shooting some 3D footage with 2 Canon 7D's for the month or so with pretty good results.

I'm using a simple rail system and placing the cameras next to each other and also toe-in to a common frame. I use prime fixed lenses - 2 28mm 2.8, 2 50mm 1/4 lenses and shoot at 1080/23.98P. For outdoor photography I find that it's necessary to use a 3 or 6 ND filter for bright days as the 200ASA / 1/50 shutter isn't slow enough for that much light.

All in all with this rig, you can shoot very nice long shots and scenics with very good results. I sync the cameras with a simple film slate clapper and line up in post easily. For post I have found the Stereo 3D Toolbox FCP plug in to work very well, however I am curious about the Bororo 3D plug in for Sony Vegas. If there is a more complete tutorial on this software I'd appreciate being directed towards it.

For any subjects closer than say 20-30 feet a mirror rig is required as the interaxial of the lenses is far too wide even at the closest spacing on the rail. I too am curious about the smaller form factor of the new Rebel and await it's arrival to be able to measure the interaxial distance.

For those closer shots and for sync sound shots I'm putting together a mirror rig much like Alistar's using 2 Sony EX cameras and 2 NanoFlash recorders genlocked and timecode synched. I'll be utilizing the 4:2:2 100MBs I-Frame only codec to insure frame to frame accuracy, but I'd be delighted to hear that a lower data rate NanoFlash codec would work as well if anyone knows.

I'll be uploading a few sample clips to Vimeo in the next few days and I'll start a new thread to post the URL - the clips will be in full color Anaglyph mode.

[Adam Stanislav]

Originally Posted by Bruce Schultz

I am curious about the Bororo 3D plug in for Sony Vegas. If there is a more complete tutorial on this software I'd appreciate being directed towards it.

There will be eventually. I have diabetes, so I have days when I can just code, code, code, or write, write, write the documentation, and then I have days when my energy is so low I am a zombie and cannot do anything. And the last few days my energy has been at the bottom.

But I will get my high energy days again and will write more documentation. I have also ordered the nanoFlash in the hope of using it to grab video directly off my computer screen. I am hoping to produce a DVD which explains everything about the plug-in. Of course, I still have more work to do with the plug-in itself and see no point in producing the DVD before the plug-in has everything I want in it.

For now, if all you need to do is combine a left and a right video, follow these instructions. If you need to combine multiple left and right tracks, there is a Bororo 3D Single View under the Video FX section of Sony Vegas. Apply the appropriate left or right view to each track. Choose Left/Right or Above/Below as needed for the left tracks, and the same with Swap Right/Left selected for the right tracks. You can use that on any number of tracks. In that case, your Compositing Mode should be Source Alpha (this is the default anyway).

Or for anaglyphs, with the same Bororo 3D Single View pick the appropriate anaglyph and, again, select Swap Right/Left for the right tracks. This time your Compositing Mode needs to be Add with one of the two tracks being the child of the other.

If you need to place a 2D background behind it all, just place it at the bottommost track for anaglyphs and everything other than Above/Below or Left/Right. For the latter two, select the Bororo 3D Double Vision from Video FX and select either Left/Right or Above/Below. This is only for 2D tracks that you want in the background. You do not need it for anaglyphs because the anaglyph of a 2D video is the 2D video itself.

Just make sure you have the latest version (currently 1.2.1, build 7 - this appears on all the Bororo 3D dialogs).

I hope this can get you started for now. I will keep you all posted when I write more docs.

[Bruce Schultz]

thanks for that information and URL Adam, I hope you are feeling better soon.

[Sareesh Sudhakaran]

Originally Posted by Bruce Schultz

I've been shooting some 3D footage with 2 Canon 7D's for the month or so with pretty good results.

I'm using a simple rail system and placing the cameras next to each other and also toe-in to a common frame. I use prime fixed lenses - 2 28mm 2.8, 2 50mm 1/4 lenses and shoot at 1080/23.98P. For outdoor photography I find that it's necessary to use a 3 or 6 ND filter for bright days as the 200ASA / 1/50 shutter isn't slow enough for that much light.

All in all with this rig, you can shoot very nice long shots and scenics with very good results. I sync the cameras with a simple film slate clapper and line up in post easily. For post I have found the Stereo 3D Toolbox FCP plug in to work very well, however I am curious about the Bororo 3D plug in for Sony Vegas. If there is a more complete tutorial on this software I'd appreciate being directed towards it.

For any subjects closer than say 20-30 feet a mirror rig is required as the interaxial of the lenses is far too wide even at the closest spacing on the rail. I too am curious about the smaller form factor of the new Rebel and await it's arrival to be able to measure the interaxial distance.

For those closer shots and for sync sound shots I'm putting together a mirror rig much like Alistar's using 2 Sony EX cameras and 2 NanoFlash recorders genlocked and timecode synched. I'll be utilizing the 4:2:2 100MBs I-Frame only codec to insure frame to frame accuracy, but I'd be delighted to hear that a lower data rate NanoFlash codec would work as well if anyone knows.

I'll be uploading a few sample clips to Vimeo in the next few days and I'll start a new thread to post the URL - the clips will be in full color Anaglyph mode.

I am keen on getting a couple of Rebel 2tis myself and start to experiment. My main concern is definitely the 'closer than 20-30 feet' bit. Being interesting in telling stories on a low budget, a beam splitting rig is what I probably need. ET has a rig for the 5d/7d, but I have no clue how they manage sync and other stuff.

You mentioned you used a clap to sync. When the camera records, it does so in H.264 in a MOV file - this I'm assuming is not broadcast quality, but I guess is good enough for films. How can you precisely match each frame? Since each camera is slightly different, does the encoding make things worse - or is it a non-issue? What if I'm using a 16GB SD card and recording a single take for about 30 minutes (4GB gives 12min)? Will I still have sync at the tail end of my video?

Can we use a zoom lens at all for this 3d rig? I understand it would be a very difficult task to set the lens correctly, but are there any systems in place for this that make it achievable?

Would love to see those test shots you're doing! Thanks.

[Alister Chapman]

Just a couple of points:

While you can sync a pair of nanoflashes to start and stop recording at the same time, it is the cameras that must be synced together via genlock or some other means to prevent the stereo from breaking down during camera moves or any on screen motion. The NanoFlash is just a recorder, it is the signals arriving at the recorder that must be in sync so for frame to frame accuracy the cameras must be genlocked or controlled in such a way as they run in sync.

I use the NanoFlashes at 50 Mb/s Long GoP when I need longer record durations and the pictures are just fine. For most projects I shoot at 100 Mb/s. Make sure you have the new firmware that allows you to name the cards and keep the card names after a format to help you keep track of your left/right clips.

If your going to use a mirror rig with a vDSLR you need to check that the mirror has as near to 50/50 split as possible. Many low cost rigs use Prompter mirrors which have a 30/70 or 60/40 split. This means that the cameras will have different light levels, thus different apertures and depth of field. With small chip video cams the difference in DoF is less noticable but with vDSLR's and large sensor cameras it is a much bigger issue.

[Bruce Schultz]

Originally Posted by Sareesh Sudhakaran

You mentioned you used a clap to sync. When the camera records, it does so in H.264 in a MOV file - this I'm assuming is not broadcast quality, but I guess is good enough for films. How can you precisely match each frame? Since each camera is slightly different, does the encoding make things worse - or is it a non-issue? What if I'm using a 16GB SD card and recording a single take for about 30 minutes (4GB gives 12min)? Will I still have sync at the tail end of my video?

Can we use a zoom lens at all for this 3d rig? I understand it would be a very difficult task to set the lens correctly, but are there any systems in place for this that make it achievable?

I have not, nor expect to use the Canon 7D rail rig with sync sound. It is a "training wheels" rig for me so I have just been using it for obtaining footage which I can then analyze in FCP using Mr. Dashwood's 3D plugin to see where the flaws in my camera adjustments are. However, so far I haven't detected any problems of picture sync between the two data streams on short 2-5 minute shots. I recently shot a series of boats and kayaks in a harbor (at a distance with 50mm lenses) and had no trouble syncing the two streams at all. Using a clapper at the head and a tail slate also is a very easy way to find the first common frame of any clip(s) and my tests so far have held sync right up to the tail slate - as I mentioned for short clip bursts.

Since I use prime lenses, zooming is not part of the equation. I recently toured a very high end 3D facility in Los Angeles. Their zoom lenses are computer locked and their proprietary software not only tracks the two zooms but adjusts the camera mounts for physical discrepancies between the cameras also. Very sophisticated and very expensive at roughly $50,000 USD rental per day per 2 camera rig. So zooming seems to be a slippery slope in 3D. I'd love to hear that it isn't though.

[Alister Chapman]

Getting the two cameras in sync for 3D is crucial if anything moves in the shot, especially if anything is moving across the frame. Imagine a shot with a car traveling through the frame. If the cameras are not completely in sync, the position of the car when the image is captured will be slightly different for the left and right views. This will in effect move the car forwards or backwards in 3D space as the cars positional difference between the left/right frames will alter the convergence/divergance for the car. The static parts of the frame will be unaffected. Imagine also a shot of a person walking or running, if one camera takes its shot slightly behind the other, the persons legs will be in a different part of their stride so the left eye will see legs in one position while the right eye will see legs in a slightly different position and the 3D will break down.

Also consider what happens when you pan. If one camera captures its image slightly ahead of the other then the 3D depth will appear to either compress or expand as the cameras are panned because the left and right images will be shifted slightly left or right with respect to each other. Even at 30 frames per second a half frame sync difference would equate to a half degree difference between the 2 cameras with a 5 second 180 degree pan, which is not all that fast.

It's not just a case of getting the cameras to go in to record together, as the it is the video streams that the cameras are producing that need to be in sync, so you need both cameras to switch on and power up in sync.

At 24P (the slowest typical frame rate) it is traditional to use a 1/48th shutter. To ensure that both cameras are exposing for at least half of the open shutter period together they must be within roughly 1/100th of a second of each other. This is the absolute minimum needed and wont be ideal for any fast movement. Ideally you want cameras running within 1/1000th of a second of each other. This can be achieved with a Lanc controller or genlock, but I know of no way of doing this with the canon vDSLR's.