DSLRs For Filmmakers – One DPs Perspective
“To the the man who only has a hammer, everything he encounters begins to look like a nail.” – Abraham Maslow. Likewise, a Cinematographer with a DSLR might be tempted to use it for motion picture projects, even though it may not always be the best tool for the job. Meanwhile, these cameras are being embraced by distinguished Cinematographers such as Shane Hurlbut, ASC, Gale Tattersall, and Rodney Charters, ASC, with exceptional results. These are DPs who could probably have access to just about any camera they care to choose. So are these cameras the game changing panacea for Filmmakers, or does the “Man-With-A-Hammer” Syndrome better explain why we are suddenly hearing so much news of the HDSLR as the seemingly ubiquitous motion picture camera?
In case you are not into photography and were too embarrassed to ask, the term “DSLR” is an acronym for Digital Single-Lens Reflex. The “SLR” portion of the name refers to the use of a mirror in the optical path in order to divert the image to your viewfinder exactly as it will be captured. When the shutter is released on an SLR, the mirror flips out of the path to directly expose the film or digital imaging sensor; (although not the way it works for shooting video, but more on that later.) This through-the-lens viewfinder compares to a separate viewfinder image which can result in problematic disparity as was common in years past, or only being able to view the image on an LCD, as with most digital pocket cameras. The “H” preceding DSLR refers to the relatively new ability to shoot HD video.
Although I personally own an extensive collection of lenses and SLR camera bodies, with film models dating back to the 1970’s, and digital models only a few years old, none of them offer the function of shooting HD. Since I have other cameras in my inventory that are specifically designed to shoot HD and beyond, I haven’t found it necessary to scrap these trusty old still cameras in order to get new ones with this feature. That is not to say I would not consider this to be a valuable feature if I were to buy a new DSLR. The versatility to use one camera system for a variety of projects is appealing, and if I had one, I would try to find interesting ways to take advantage of this utility.
Companies such as Panasonic, Nikon, and especially Canon are now embracing the idea, even if their still cameras were never really designed for this purpose. The genesis of adding HD capabilities seems to have begun when news gathering organizations like Reuters asked the DSLR manufacturers if motion capabilities could be added so that photojournalists on assignment to capture stills could also shoot some video coverage for use on the web. For this purpose 30fps in relatively short bursts of HD with limited sound capability fit the bill nicely. However, Filmmakers, who have been known to use any imaging device at their disposal to make their movies, from DV to Cell phones, immediately started asking for more features better suited to their particular purposes.
Canon has so far been the most responsive with a firmware update allowing more industry standard frame rates and improved exposure control. Originally locked at 30fps, (or 25fps for PAL,) they now offer the more post friendly 29.97fps, and the cine standard 24fps or 23.976fps. EOS Utility Software comes free with the Canon cameras and lets the user create very precise custom looks for the camera that can be saved, shared and updated. When tethered to the camera via USB, the software also provides a live monitor view on your computer desktop and remote control of virtually all camera adjustment controls. They also increased the audio sample rate to 48khz., and added the ability to defeat AGC, (automatic gain control) to allow for manual preset of audio record levels; (although you still cannot adjust these levels while rolling.)
Recording durations have yet to pass about 12 minutes of run time. Since they were not originally designed for continuous operation, heat was an issue, but interestingly, this limit was reportedly more a function of European import taxes. It seems that if the cameras were able to record more duration, they would jump out of the still camera tax category and be considered a video camera, subject to a much higher EU import tariff. Since 12 minutes of run time is about the same as you would get with a 1,000 foot roll of 35mm film, and with only a matter of seconds to swap CF cards to continue shooting, it is plenty for most filmmaking requirements.
So what are some of the pros and cons of using DSLRs for Cinematography? For the purposes of comparison, I will consider the Canon 5D Mark II, the model which has so far gotten the most traction for motion photography. The extremely large sensor is about 2.5 times larger than the RED Mysterium, Alexa, or F35, as well as the 35mm film format used predominantly for mainstream motion picture and television production. In theory, a full frame sensor should have better image quality across the board, but the Canon doesn’t use all that resolution to full advantage in the video mode. The camera utilizes line-skipping, (and possibly binning,) to shoehorn all that sensor data into a 1920X1080 8-BIT H.264 MPEG-4 file. This has the unfortunate result of sometimes causing artifacts such as moire, banding, and aliasing, with resultant headaches down the post production path. However, the camera uses nearly all of its full-frame 24x36mm CMOS sensor for light capture which helps it create beautiful images at very high sensitivity, (whether still or motion.)
Another consequence of the large sensor is that it makes for razor thin depth of field. While shallow depth of field can be a powerful cinematic tool, it needs to be carefully managed to avoid soft focus, and using lenses for cinema that were designed only to shoot stills on these cameras is especially challenging. Although the optics can be excellent for the application for which they were designed, problems arise in trying to use them for motion picture photography. When a still photographer zooms and focuses, then frames his shot, he is not bothered by image shift or breathing, but these can be pretty funky effects in a movie, not to mention that focus marks are not repeatable and the short throw, designed to help a photographer easily grab focus, is a detriment when a Camera Assistant is trying to line up precise distances with engraved markings on the lens. In addition, still camera lenses are calibrated only in f-stops, which are only a theoretical estimation of how much light passes through the iris; plus the weight and front diameters of still camera lenses vary widely, which increases set up time for lens changes.
In answer to this dilemma, companies such as Illya Friedman’s Hot Rod Cameras have begun to offer modifications to the HDSLRs in order to allow the use of PL mount motion picture lenses. He started with the Panasonic Lumix DMC GH1, but per popular demand, is now starting to modify the Canons. In addition to changing the mount, he also offers integrated lens support which is quite necessary when adding the kind of heavy lenses that will be used in normal, (read tough) motion picture production environments. People I’ve talked to who have used these modified cameras have been very pleased, but a possible downside is the danger that it can void the camera manufacturer’s warranty, and it should also be noted that many older PL mount S35mm format lenses may not have enough coverage area to handle the large “full frame” 5D Mark II sensor. Companies such as Zeiss are also starting to offer their new motion picture style Compact primes with interchangeable lens mounts, including the native Canon EOS mount.
Another obvious plus for the HDSLR is its relatively small form factor. A stripped down camera can get into positions where no full size cine camera could dream of squeezing into. It’s easily mounted in such places as onto helmets or right behind a car’s steering wheel for unique POVs. However, once encumbered by all the accessories and support framework that most Cinematographers will want to add on for increased utility, it can be a different story. Since the cameras were designed to be framed through the viewfinder, or with a good view of the LCD on the back of the camera, it can be difficult to frame in any position where your head is not directly behind the camera body. Although the camera is relatively light weight compared to most cine cameras, holding one out in front of you for any length of time will be strenuous. Third party outfitters like Redrock Micro and Zacuto have come up with elegant rigs to hold various accessories in a variety of positions, and allow easy handheld options; but these “erector sets” do add to the overall bulk of the camera. Some common accessories include either an external monitor mounted on the camera, or a transmitter to send the signal to an off-camera monitor. High quality monitoring and good follow focus apparatus is critical because, as mentioned previously, the depth of field can be very shallow. Even if you’re going wireless, the gears, motors, and transmitters all add to the camera’s overall girth and certainly to its cost.
Although audio features have improved, and are great as a scratch track, audio recording is still generally agreed to be in the sub-professional category. Inputs are tiny 1/8″ stereo plugs, as opposed to three pin balanced XLR, and the camera preamps can be noisy. Again, aftermarket items can be implemented with adapters to XLR, quiet preamps, real volume pots, (not menu options), and solid headphone jacks for monitoring; (examples are BeachTek and JuicedLink.) Manual levels are still not adjustable while rolling and double system recording is recommended for professional applications.
Even in cameras with the best audio specs, double-system recording is the norm for motion pictures. It’s normally pretty easy to sync up sound files, but with the HDSLR there is currently no Timecode In/Out facility on the camera, and the actual camera recorded file has no timecode. Third parties are helping here as well with software that can sync sound and picture in post, such as PluralEyes. Final Cut Pro now has a free Canon plug-in allowing the Log and Transfer function to add timecode as the files are ingested and transcoded to ProRes HQ. In any case, count on some extra steps in post to deal with HDSLR sound and picture.
Also worth noting is the “Jello-Cam,” effect caused by the rolling shutter of the CMOS sensor. It can reportedly show up when panning quickly, especially across vertical lines in the frame, which can become “squiggly.” To a greater or lesser degree, other CMOS cameras, such as the RED, also suffer this phenomenon, but I’ve not actually been bothered by it in my shooting.
I’ve mentioned a number of shortcomings, but to be honest, these are mainly just the result of using the camera to make professional motion pictures, a use they were never really designed for. Yet with all these “deficiencies,” there must be a reason they are in such demand, and that is simple; they make awesome images. For samples of what can be achieved in the hands of talented Filmmakers, I suggest you visit the website of DCS member Shane Hurlbut, ASC: http://www.hurlbutvisuals.com Be sure to check out the movie he shot with the Canon 5D Mark II, entitled “The Last 3 Minutes.” He also shares generously here his thoughts about shooting HDSLRs via his blog and behind the scenes videos.
Another thing you gotta love about the HDSLR is the price/performance ratio. Although you could easily sink $10K into a 5D Mark II with good quality glass and accessories to aid in shooting motion, that’s still pretty inexpensive compared to other high-end HD cameras, plus you get a top quality still camera in the bargain. And new models with smaller “4/3″ S35 size sensors such as the Canon 7D and Rebel T1i now offer lower cost alternatives with HD shooting capabilities. An HDSLR may not be the best choice for your “A” camera on a feature, or even a run and gun ENG shoot, (where I feel it’s usually better to have a larger focal range and more depth of field,) but it does a lot of things well and has certainly earned it’s place at the table. When they start offering RAW format motion recording, as they do for stills, it’s only going to get better. I doubt if I’ll ever buy a still camera again that can only shoot stills.
Posted in DSLR Filmmaking, Filmmaking, HD Video - 2 Comments »
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Great summary of where we are today. The pace of change has been exhausting and exhilarating! What an exciting technology boom!
I’ve had the pleasure of talking in depth with each of the cinematographers mentioned here – Rodney Charters, Gale Tattersall, and Shane Hurlbut in my podcast. They each acknowledge the weaknesses of these cameras, but are excited by their potential. I like the way Shane puts it regarding mastering the Canon 5D Mark II – “they have beaten me up!” And yet, even with those limitations these cameras have opened up a door to shooting in a way that was not easy to do before – such as in the cramped quarters of the set for the House season finale. Or the unique POV shots that Shane’s “Last 3 Minutes” exemplify. The gatekeepers of traditional cinema have been toppled – for today’s generation of video DSLR’s make possible unprecedented affordable filmmaking. Of course, you still have to develop the art and craft and telling a story. Not everyone with a 5D Mark II are going to be instant ASC’s.