Bullet Time

This video was just posted on Reduser, the discussion forum and news outlet for Red Digital Cinema:

National Geographic Glidetime

It got me thinking about the history of the effect commonly referred to as “bullet time.”  The first instance I remember is probably the one everyone remembers, The Matrix (this clip is meant to showcase the audio, but it’s the one I could find that only includes the bullet time scene):

[youtube https://www.youtube.com/watch?v=WhxbYTMNMxo&w=425&h=349]

This Wikipedia article gives a good summary of how it’s done and where it came from and mentions the first music video to use bullet time, Midnight Mover by German metal band, Accept:

[youtube https://www.youtube.com/watch?v=9el2lg2olpE&w=425&h=349]

It’s not quite what I see when I think of bullet time, but the beginnings are there.  And the song…!  That was 1985, but in 1980 Tim MacMillan was developing the “Timeslice” technology while working on his B.A. at Bath Academy of Art. You can see his current work here, which is done with bazillions of DSLRs, but this collection of early work is amazing.  Be sure to read the explanation of how it was done:

Tim Macmillan Early Work 1980-1994

I’m not sure which pieces were made while he was in college, but wow.  I especially like the double-exposure light painting fire.

Speaking of light painting, here’s an early lightwriting animation by German group, Lichtfaktor that has nothing to do with bullet time:

[youtube https://www.youtube.com/watch?v=tlWnpz0Di90&w=560&h=349]


Relationship of lens to sensor or film size

Interchangeable lenses are becoming more and more common on video cameras, but the wide variety of sensor sizes makes it difficult to talk about the focal length of a lens in a way that makes sense.  If you put the same 50mm lens on a Canon 5d and a Panasonic AF100, for instance, you will get a considerably different image.  This is because the 5d has a 35mm “full frame” sensor and the Panasonic has a much smaller four thirds sensor.  This is a confusing topic, but I’ve found both a useful tool and a great video from AbelCine that are a big help.

First, the Field of View Calculator shows you visually how the crop of a sample image would compare, given two different sensors or film sizes.

Second,  On AbelCine’s Cine Technica blog, Mitch Gross does an excellent job of explaining all this in his video post, “A Lens is a Lens is a Lens.”

Rechargeable Batteries

Media production is a battery-heavy field, and for good reason.  We need to be able to power all manner of tools and devices reliably in an unpredictable variety of places.  If the conditions and location of your production are predictable, such as in a TV news studio, you can power most things from wall AC power, but even in that situation, you’re likely to use batteries in a wireless lav mic.

Most cameras—video and film—use purpose-built batteries made either for a specific brand and sometimes model, or more general-use batteries made to power a variety of items.  The common feature here is that they are all rechargeable.  This makes sense, as you could easily go through two or three of the Sony batteries on the right in a day of shooting and constantly replacing these would be costly.  With smaller devices, like hand-held audio recorders or wireless lav mics, though, the typical procedure has been to buy lots of disposable batteries and keep throwing them away as you use them.

One of the main obstacles to replacing AA or 9v Alkaline batteries with rechargeables has been how quickly they discharge.  It was difficult to keep a stock of batteries available for use without having to constantly charge them.  In the past few years, however, several manufacturers have made batteries that feature a low self-discharge rate.  That means that if you charge them and then put them in a drawer or case for a year, they will still have a reasonable percentage of their total capacity available (75-90%).  Their total capacities are still lower than disposables, but the cost savings and environmental benefit add to the appeal and make rechargeables a more viable option in media production.  There is currently a wider selection of AA batteries available and there’s a good review of the options here.  Several manufacturers, including Rayovac, PowerEx, and Tenergy, also make low self-discharge 9 volt batteries.

High-end/low-end tools

On the high end, big-time cinematographer Roger Deakins appears to be embracing digital cinema.  There’s a good summary here of comments he has made on his forum about film vs. digital and shooting with the Arri Alexa.  He seems to be saying that he won’t be shooting film in the future, but at the same time dismissing the binary film vs. digital comparison and adding here that “a camera is just a camera.”  While it is clearly significant that such a well-respected cinematographer has taken this step, it’s also not surprising, as he was the first to use the Digital Intermediate on the entirety of a major motion picture in O Brother, Where Art Thou?

Another significant step in high-end digital cinema was recently announced in Sony’s release of the F65—a digital cinema camera in their CineAlta line that shoots an 8k image.  They’re conservatively calling it “Beyond 4k,” because it’s currently meant to capture an oversampled image from which you derive 4k, 2k, and HD images.  They also make the storage and exhibition system, so you could, theoretically, stay Sony from shoot to theater.  There’s a video on Sony’s site where Curtis Clark, ASC extolls the virtues of the F65.  Note the extensive use of the camera on a Steadicam, both walking and riding on a dolly.

That’s all well and good for Hollywood, but what about those of us without millions of dollars to spend?


Atomos Ninja

Obviously, the DSLR “revolution” fits that niche to some extent, but potentially more important than any low-end camera advance is the recent advances in camera-connected capture technology.  I have only a vague memory of the betamax system on the left, but we may be headed towards something similar.  Using the HDMI out from a wide variety of recent cameras, from DSLRs to prosumer video cameras like Canon’s VIXIA line, to the latest removable-lens large-sensor cameras, you can now get past the limitation of heavy compression to fit video on CF or SD cards.   The answer is a new crop of external video recorders like the Atomos Ninja and the AJA KiPro mini.  Both record using 4:2:2 chroma subsampling to your choice of ProRes formats (HQ, 422, Lt).  What does this mean?  Less compression all around and a file that fits neatly into a Final Cut Pro-based post-production workflow.  The Ninja is controlled via a touchscreen that doubles as a monitor and saves files onto any 2.5″ (laptop-size) hard drive you feed it.  The KiPro Mini doesn’t have a monitor, but it appears to be a bit more physically robust.  It also includes two analog XLR audio inputs and records to Compact Flash cards.