Tag: digital technology

Kazimi on 3D: part 1

Hazardous - production stills 4

Ali Kazimi is an award-winning filmmaker. Since 2008, he has been researching stereoscopic 3D digital cinema at York University, where he is an Associate Professor in the Department of Film.

Q. Why is there this sudden groundswell of interest in 3D?

The current stereoscopic 3D is propelled by the exponential rise in digital technology in film production, coupled with the phenomenal success of James Cameron’s Avatar. Really, much of the growth in S3D is due to Cameron’s championing and use of digital S3D. Cameron himself did not come to S3D overnight, he spent the decade before Avatar experimenting with making underwater docs with different degrees of success. In fact, his underwater experience reveals itself not only in the very comfortable 3D experience he was able to deliver, but also in the flora of the imagined world which looks and behaves very much like underwater plants do.

However, it is his S3D experimentation that is critical to acknowledge and it is instructive in many ways – or to put it differently, S3D has a steep learning curve. The biggest challenge I feel is getting a grasp on the fundamentals of perception, how we see depth. Stereo vision, or ‘stereopsis’ as it is known scientifically, is the process by which the brain takes in the 2D images from the left and right eye and fuses them together into a single 3D image. However, stereopsis is only one way in which in the human brain perceives depth. We also use a number of other visual cues, called monocular cues, such as perspective or the familiar size of objects to determine spatial relationships.

Technically, S3D camera systems mimic the way we see. We use two cameras each offset by a certain distance, called the inter-axial (IA) distance, to generate two identical from images from slightly different perspectives, similar to those between our two eyes. The images have to be in perfect sync with identical focus, depth of field, colour and contrast, this is easier said than done. The mechanism for shooting stereoscopic 3D, known simply as rigs, therefore consists of two cameras either side-by-side or at right angles to one another with a partially silvered mirror at 45 degrees in the middle.

In terms of both composition and pacing there is much that is still unknown, filmmakers have to learn how to see the world around us with the z-axis in mind.

A couple of months ago just I saw a screening of shorts, commercials and music videos screened at the TIFF Bell Lightbox. The program, called ‘Selected Package’, had a wide range, from those with high production values to lo-tech DIY retro-inspired music videos. The latter were screened with the Red/Blue, anaglyph format. I have rarely come out of a screening with such acute eyestrain and headache. Once again, these music videos painfully drove home the difference between bad 2D and bad 3D, in that poorly produced S3D can be uncomfortable and even painful. Filmmakers have to recognize that their S3D work can have an immediate physiological impact on the audience. In fact this is the very reason why filmmakers have to step way back and truly re-examine how we see.

On the other hand, Wim Wender’s film Pina is a real masterwork and a true landmark in S3D filmmaking. In my view, the first feature film made solely for S3D, one that explores its immense possibilities with such inspired grace and virtuosity.

Wenders’ keynote address at our Toronto International Stereoscopic 3D conference was one of the most amazing artist talks, and a truly inspirational speech on how he came to 3D and how filmmakers should engage with 3D (read the transcript here). Pina is exciting because it was designed solely as a 3D film, whereas I have long maintained the almost all other 3D content is designed to work in 2D as well. Consequently there can only be limited exploration of a new cinematic language. More on Pina a bit later.

What is it that you have to learn? Theory or hands-on?

On the technical side, digital projection has made it possible to deliver a pretty seamless 3D experience, it is another matter that many cinemas don’t have proper projectors resulting in relatively dimmer image. Of course this is the last but crucial stage in the entire digital workflow.

In some ways the ‘Avatar effect’, as I often refer to it, has been a mixed blessing. The studios and the television manufacturers all jumped on the bandwagon. S3D sets are now increasingly on the market and prices are coming down fast, the problem is the dearth of content. To create content one needs more than tech, training and accessibility is critical. As I have said earlier, S3D has a steep learning curve and there are no short cuts, it will take time to develop a critical mass of filmmakers and technicians.

The most critical position is that of the stereographer – a stereo expert who should ideally be at least consulted during pre-production, who is on the set during production working with the camera rig and who then again at least consults through post-production and during the final colour and stereo-grading. Stereographers are hard to find, in this new field many people claim to be one after doing a workshop or two, one has to be really careful. Errors made in production such as the depth of a shot are impossible to “fix in post”.

Thanks to Tobi Elliott for her help with the blog.

HD for Dummies

Philippe Lavallette - les réfugiés de la planète bleue
DOP Philippe Lavallette at work with an HD camera on Les réfugiés de la planète bleue.

These days, most documentaries are shot in HD, high definition. Seems to make sense, doesn’t it, since you can buy a high definition camera for just a thousand dollars! But does this mean that all HD is one and the same thing, and that you get as good an image with a thousand-dollar camera as with one that costs 50 times more? You guessed it, you don’t.

A few weeks ago I had the privilege of taking a course in HD workflow at PRIM, in Montreal, a resource centre for artists and filmmakers. (I am a member, we did the post-production for my most recent films there.) It was an opportunity to get an answer to my most pressing question: what does HD really mean, how do you know what quality you are really getting, and can you combine different kinds of HD formats without noticeable quality differences ?

So, in case you were asking the same question, here’s a short summary answer. The quality of a digital image is partly, but only partly, defined by the resolution, measured in lines of pixels. Standard Definition (SD) has 480 horizontal lines. The most common HD resolution is 1080 (horizontal) x 1920 (vertical) lines for a 16:9 image, but can be lower (720 for the vertical count is common) or higher (up to 4000 for a camera like the RED).

However, the actual quality of the image doesn’t depend only on the resolution. It also is a direct function of the compression, the size and nature of the image sensor, and the quality of the lens.

Compression is a way to encode the information to save space on whatever support the image is recorded on. It is expressed in three-part a formula as in 4:4:4 (uncompressed) or 4:2:2 (a $5,000 prosumer camera like the EX-1 which I use.) The inevitable cost of compression is a loss of definition and detail, and reduced margins for colour correction and visual effects in post production.

And the sensor. The smaller the sensor, the less detail you will get, and– counter-intuitively– the more depth of field you will get. More depth of field might sound like a good thing to the neophyte, but actually film makers tend to want the opposite, to achieve more of a ‘film look.’ (Main subject in focus, background out of focus, for ex.) Both Sony and Panasonic are just coming out with cameras that will make it possible to shoot video with a very limited depth of field, that will be another small revolution in video production.

With the help of PRIM’s excellent staff, we did some tests with the different cameras I use. To summarize the conclusion: the small and cheap HD cameras give a surprisingly good result, but you don’t get the same quality image as with a more expensive one. If you want to combine to two, the smaller/cheaper cameras should be used in good lighting conditions.

Thanks to Tobi Elliott for help with this post.

Documentary and globalization: favouring understanding

Age of Stupid - Sydney
A still from the documentary "The Age of Stupid", directed by Franny Armstrong

I have just spent two weeks teaching at Whitman College in Walla Walla, Washington State. More on my course another day, but I also had the opportunity to speak to the students and faculty about Documentary in the Context of Globalization.

I talked about how the new digital technologies have democratized access to audio-visual production and how the web has made it possible to instantaneously distribute videos worldwide. This has opened up a two-way street, making local stories available to the world, and bringing the world (or stories from elsewhere in the world) to audiences just about everywhere.

To illustrate my points, I showed excerpts from three films. Burma VJ is one I wrote about on my blog earlier. The film documents the use of small digital cameras by courageous video journalists – VJ’s – to reveal what goes on inside the Burmese dictatorship. With digital cameras and satellite uploads they distribute images worldwide within hours. Their work made all the difference during the 2007 uprising led by Buddhist monks across the country.

Another example I used was the video of the killing of a young Iranian woman during the 2009 protests in that country. It graphically showed her dying moments, and really touched people emotionally. Thanks to the web and cell phone – Twitter was particularly instrumental – it spread like wildfire, and actually helped change the relationship of forces between the regime and the opposition.

As an example of how the new production and distribution context has allowed people who did not traditionally have access to the resources to express themselves audiovisually, I used the amazing Wapikoni mobile experience, which has been running for six years in Quebec. Young aboriginal people have been given training and access to production facilities, and the result is impressive. Many of their films have been presented at festivals and won awards.

For some filmmakers, the starting point is not local but global. That was the case with the 2009 film The Age of Stupid by Franny Armstrong. The premise, established with much aesthetic panache, is that while the world has gone to ruin, one man (played by Pete Postlethwaite) remains in the Global archive in 2055. His archives reveal the stupidity of the people of our era who knew the world was on the road to perdition but didn’t act – stories set, naturally, in our own time.

Finally, I spoke about the phenomenon of immigrant directors (or children of immigrant families) making films about their home countries in the ‘developing countries’. Having access to the funding mechanisms of the richer countries as well as an intimate knowledge – or at least personal connection – to their country of origin, these talented directors have made some great films. Ali Kazimi’s Narmada – A Valley Rises, Rithy Panh’s films about Cambodia are good examples, but I chose to show an excerpt of Up The Yangtze by Yung Chang (NFB & EyeSteel Films).

There are increasing numbers of excellent films coming out of the countries in the South. As a member of the board of the Alter-Cine Foundation, I am able to see the incredible diversity of projects from Asia, Africa and Latin America looking for funding every year. Just reading the proposals, one gets a sense of the many aspects of reality which are not adequately covered by our television networks.

Conclusion – it sound a little simplistic when summarized, but it’s true: by offering a more in-depth treatment of other realities, documentaries contribute to understanding and awareness between peoples.

Thanks to Tobi Elliott for her help with this blog.