The Basics of Making 3D Videos

The Basics of Making 3D Videos

3D video is still in its infancy, but for early adopters, the challenges of making a 3D video to air on your TV are exciting. Videomaker looks at the gear you'll need to create for 3D video by talking to some experts already excelling in this emerging video market.

So you walked out of the theater after seeing Avatar in 3D for the third time and you're thinking, "I want to make a 3D video!" Obviously if you can marshal the same resources Director James Cameron did, you probably will. More than likely you'll have to start out more modestly. But where to start? What gear and software will you need? How do 3D videos get made?

Understanding the Technology

Two primary methods of acquiring footage are involved with 3D films headed for theatrical release. One uses two separate cameras side-by-side for direct stereoscopic filming. The other converts a standard 2D movie into a 3D film. Many agree the conversion method is inferior to shooting stereoscopically from the start. There are tons worth of technical information concerning what potentially is needed and how to make 3D videos.

However, the basics for stereoscopic 3D video creation are fairly simple to grasp. First you'll need to understand basic 3D terms. Next, you'll need to know what format of 3D video you want to make. Lastly, you will need a basic understanding of cameras, how to stabilize them and the editing software that you will need to complete your video.

You first need to understand that making 3D video is more challenging than shooting regular 2D video. There will be more planning, gear and work involved to complete the project. So you need to understand some basic 3D video terms. Stereoscopy is any method capable of recording 3D information or creating an illusion of depth in a 2D image. Stereoscopy has been around since the late 19th century by taking two identical photographs and putting them onto a stereo viewer. The device takes advantage of the distance between our eyes, known as the inter-ocular distance, and fools the viewer's brain into seeing a 3D scene.

In the 21st century there are more technical ways to achieve the same result. The more common method we'll examine is the Complimentary Color Anaglyph (CCA) particularly the red/cyan variety. An anaglyph is a stereoscopic technique using two overlapping images. By using two complementary colors representing each eye (i.e. red-left, cyan-right) the effect becomes much more convincing. To create a believable 3D effect using the CCA method you'll need: 2 same-model cameras, a side-by-side camera mount, a stereoscopic player, a monitor that allows you to view 3D or two video streams, a stereoscopic calculator, 3D glasses (red/cyan) and editing software which allows more than one video track.

To break down 3D video creation into its basic points, I spoke with two innovative videographers; professional Jeff Cools, and 'Mad Genius' hobbyist Pavel Houda, about their gear and approach to the format. For me a long-time videographer and filmmaker, the conversation was eye-opening.

VM: Is making 3D videos your job or hobby?

Jeff Cools - I've been working in video production since 1989 as my primary business and started making 3D videos in 2007. My unofficial job title is 'Preditor' meaning I do everything from pre-production to editing!

Pavel Houda - This is 100% hobby for me. I have a background in electrical engineering and computers. My job is in TV manufacturing. It has been helpful knowing the fundamentals for working with this equipment.

VM: What got you interested in making 3D videos?

Cools - I always keep tabs on what Hollywood is doing. I saw the film Beowulf in 3D and was blown away! I assessed Hollywood was banking on 3D to get people back into theaters. Until TV manufacturers can duplicate the 3D experience, theaters are the best bet. The US is currently far behind Japan and the United Kingdom when it comes to 3D television, but I like the process and want to be a part of it.

Houda - I have an old DLT-TV that's capable of showing 3D but there wasn't any way to get live 3D video on it. The obstacle was how to make 3D video without giving people headaches. My family politely watched my early attempts but took off their 3D glasses when I wasn't looking!

VM: What kind of gear do you use to make 3D videos?

Cools - To keep my work as true 3D I use two HD cameras of the same brand and model that have a genlock feature so I can synchronize the cameras. However, you can use an audio slate or a hand-clap if you don't have genlock. I also use a slide mount because the cameras have to be positioned close together as possible. If your cameras are too large to get close, you can shoot using a mirror. In addition, I use a monitor to view the two video streams. The last things I use are a Focused Iris Zoom (FIZ), a controller to sync the two camera zooms and a good tripod or stabilization unit. Oh, and a Lens Focusing Chart.

Houda - I use two camcorders side-by-side with a LANC controller. The controller allows me to sync the two cameras for up to 20 minutes similar to genlock. I link the two cameras up to a netbook computer which has stereoscopic viewing software on it. I watch the live video and the display with a set of VGA video glasses. To keep all this portable and keep the cameras aligned, the solution was mounting the cameras onto a hand-held stabilizer. With everything connected to the netbook, I can put everything in a small camera bag on my shoulder. To control the computer I use a tiny keyboard with a built-in trackball.

VM: What are the basic tools needed to shoot 3D video?

Houda - If you don't want to build a setup, you'll need to buy a professional rig. If you do, start with two cameras of the same model that will allow you to mount them side-by-side without blocking access to the LANC ports. You'll also need some kind of adjustable mount with ball heads to keep the cameras in alignment and a tripod or gimbal to stabilize them. Most important you need a controller that lets you power up the cameras at the same time. Your two video streams have to run with no variation in speed or you won't be able to sync them. If you plan your set-up well, you can get good cost-to-performance. I estimate my entire system cost about $3500.00.

Cools - Your cameras must be mounted side-by-side and your subject can't be closer than 30 inches for every inch the cameras are apart. That's the basis of the "1/30 Rule." Any closer and the viewer won't be able to fuse the images together. To see what I mean, put your thumb right in front of your face and try to focus on it.

Another component for making 3D videos is editing software that allows you to stack video tracks in the timeline and bring down the upper track's opacity to 50% for editing. You'll export two movies (one for left and right eyes) and audio attached only to the left-eye video for stereoscopic viewing. For an anaglyph, you'll make one movie red and the other cyan. This method saves money if you don't want to rent or buy 3D capable monitors. You'll have to plan out what the video will be shown on to decide the best option for delivery.

Fortunately, there is also software available to calculate the distances necessary for your camera chip sizes, closest / farthest object, and the distance your cameras will need to be apart to accurately shape your subjects stereoscopically.

VM: What are common equipment and workflow problems with 3D video?

Cools - Top of my list is syncing the cameras. Ideally you want to sync your cameras through genlock and timecode lock. But, you can sync using a timecode slate. Next is an issue using complimentary color anaglyphs. With anaglyphs you use two-color glasses to see the 3D effect. The problem is; a portion of the population is colorblind so quite a few people will be unable to view your video properly. Anaglyphs are good because they are cheaper to make since you don't need special equipment to show the final product. Without using anaglyphs, you'll need a number of hardware and software solutions to show the video streams. That gets expensive.

Houda - Your camera rig must be solidly designed and can't move or shift. It is difficult to fix the video in post if the rig moved during shooting. Another thing is there can't be vertical mismatch between the two video streams. It causes the viewer discomfort. Also, you have to watch out for Window Violations because you didn't keep track of your focus and zooms. A window violation happens when the 3D subject unintentionally moves beyond the graphics on the screen.

You need to be concerned with how large a screen the video will be shown on. On an IMAX screen you can get away with large parallax errors. For much smaller screens, keep your cameras aligned close together to avoid obvious parallax errors.

VM: What are the advantages of shooting in 3D?

Cools - The biggest advantage is the extension of your movie's shelf-life. When the run of the 3D version is done you can release a 2D version.

Houda - It's closest to how we see in nature. We see and hear in stereo, so it's a much more natural experience. It's the difference between watching black-and-white movies and color. There's more information making what you see entertaining.

VM: What advice would you give to filmmakers interested in 3D video?

Houda - I did my videos for myself, but I wanted to make it easier for others interested in making 3D films. I went through a lot of trial and error before I found what works for me. You must have patience because there are many technical issues to work out. So get a rig or build one and pick up a copy of 3D Movie Making by Bernard Mendiburu as it goes over everything you'll need to get started. It doesn't cover every problem you'll run into, so there's still a learning curve to deal with. Shooting stereoscopic 3D is both science and art, yet it's worthwhile to learn how. I don't think 3D video is a gimmick. I've seen Indie filmmakers do a better job at this than Hollywood. I strongly believe the future of 3D video is very promising.

Cools - My advice is team up with someone already shooting in 3D or do a lot of reading! That and attend a stereoscopic workshop. Most important is realize you'll be working in an industry that currently has no set rules. Eventually, film festivals will set up portions to show 3D films and there'll be far less competition. I would much rather see a 5-minute film by an Indie filmmaker shot in true stereoscopic 3D than a Hollywood movie converted from 2D to 3D!

Promote your 3D film by sending out cheap 3D glasses with your logo printed on them. Best of all, because you shot your film in 3D you can also distribute a 2D version.

Is 3D just a Fad?

Initially, I believed this wave of 3D was just another Hollywood gimmick and would fade like its predecessors. After researching this article it's plain that stereoscopic 3D video is here to stay. Many large animation studios won't do a project unless there are plans for a 3D version. Even recent segments from the ,Star Wars Saga are slated to be re-released in 3D. It won't be long before the other major film and television studios follow suit.

So should you run out and start making 3D videos? Good question. Whether you work as a professional or hobbyist, the technology is now accessible. However, as both Jeff Cools and Pavel Houda emphasized, there is a fair learning curve that can get expensive concerning time and money. Yet with proper research and experience, there are no set rules to hold you back. To my mind, that's a very exciting prospect!

Writer-producer-director H. Wolfgang Porter is a former U.S. Navel Combat Cameraman who now produces independent film and published works. He is also a Videomaker forum mediator.

Issue: 

H. Wolfgang
Porter
Sun, 05/01/2011 - 12:00am

Comments

3-D File Formats

Eickmeier's picture

I just want to know one simple, very important thing. What file formats, framerate and resolution, can we output our 3-D video to for a Blu-ray disc? I can't find this most basic information anywhere.

Thanks

Gary Eickmeier

3D formats

ralf's picture

Gary-

Most 3D TVs will accept Side By Side and Over/Under video files to display 3D imaging.

SBS is also the format supported by YouTube 3D, and involves an anamorphically-squeezed left & right-eye image both placed on a single frame.  This is NOT the same technique used by 3D bluray discs, which actually use the MVC codec to provide full HD resolution and reduced bitrates.

 

Take a look at some of the 3D YouTube vids in side-by-side mode to see what I mean.

 

Hope this helps!

 

pax-

ralf