Video is now a very big deal on digital SLRs from entry-level to pro-level, and the amount of functionality offered has been steadily improving since Nikon launched the D90 and the Canon the EOS 5D back in 2005. Most professional still photographers are well aware that shooting video is a very different discipline and the transition isn’t necessarily a natural one. There has, of course, been some very successful ‘crossovers’, but the availability of video recording capabilities on a D-SLR doesn’t necessarily mean photographers have immediately started using them.
In fact, the early take-up of D-SLRs for shooting video has been among video professionals who have been attracted by the combination of a big sensor – for it’s inherently shallower depth-of-field – compact camera dimensions and comparative affordability compared to pro-level camcorders. Additionally, the leading D-SLR systems offer extensive systems of lenses, not to mention the wide availability of ‘legacy’ lenses (as many video pros want fully manual control over the focusing and the diaphragm).
However, despite these attractions, the D-SLR is still primarily designed as a still camera so some areas of operation and control are compromised as far as working efficiently as a video camera is concerned. This has led to an explosion of accessories and add-on components designed to convert the D-SLR into a workable video camera at a professional level.
Getting Into Focus
Freelance cinematographer Matt Gormley runs his own company called Travelling Matt (visit www.travmatt.tv), working on a wide range of productions, including TV documentaries, corporate videos, music clips and commercials. He uses everything from a Sony PMW-350 EX XDCam professional video camera down to the GoPro compact ‘action cams’.
Matt’s video D-SLR of choice is the Canon EOS 5D Mark II which has been a big hit with video pros because of its 35mm-sized sensor, durability and size. However, Matt has also acquired a flight case full of accessories to rig up the 5D Mark II so it will work in the way that’s necessary when shooting moving pictures rather than stills. Simple things such as focusing need to be done differently, especially as depth-of-field and selective focus are often important creative elements in cinematography. The conventional focusing ring on the lens barrel isn’t easy to access or to operate with the necessary degree of smoothness so this requires the fitting of a follow-focus kit, converting this control to a vertically-orientated knob.
Matt says it takes about 30 minutes to build his D-SLR video rig, starting with a modular ‘cage’ or frame comprising lengths of anodised aluminium tubing and adjustable junction pieces. Some cages use carbonfibre tubes. The cage is necessary for mounting the various external components and, in turn mounts, on a fluid-head video tripod. It isn’t entirely necessary to use a cage, but given a D-SLR body has only one hotshoe mount, fitting more than one external device will quickly become a challenge.
“Shooting at a professional level, there’s no escaping the cage rig,” Matt asserts. “Ideally, you’d want to transport it built-up, but obviously this needs a big case so you may have to end up breaking it down at the end of each day.”
Matt notes that, while a pro-level D-SLR’s bodyshell may be quite strong, often the ‘fixtures and fittings’ aren’t. He cites the HDMI connections as a particular area of weakness and they’re all too easily damaged during shooting, resulting in an expensive repair. Cinematographers are the masters of invention, solving many problems on-the-go with gaffer tape and plastic ties. Matt tapes his HDMI cables to the rig some distance from the connection to avoid it being subjected to undue stresses and strains, and he used a right-angle adaptor so the plug isn’t so highly exposed.
“These are often things you learn from trial and error,” he observes, “and often it’s more about error. I’d like to see BNC cables used here because the SDI [Serial Digital Interface] connectors are much smaller and they’re metal so they aren’t as fragile. The HDMI connector is so bulky and inflexible it’s very easy to damage. It’s a domestic fitting and certainly not industrial grade.”
Front rails are fitted to the cage in order to attach a matte box and a filter holder. Of course, it makes sense for Matt to use the same filter system as he uses on the XDCam so the holder takes 4x4-inch (102 mm) glass types. Matt specifies glass over resin types because “resin simply won’t last due to the amount of times you’ll need to clean them”. Matt’s ‘must have’ filters comprise a polariser, a hard-edged ND grad and a soft-edged ND grad.
From here, it’s a case of fitting the external components one by one. Matt uses an external electronic viewfinder with a cupped eyepiece as using the D-SLR’s monitor screen is virtually impossible for video shooting. Even with a simpler set-up, Matt says it’s still necessary to use a loupe viewer which fits to the monitor screen and provides a magnified image at the eyepiece. Matt also fits an external recorder to serve as a back-up to the data being recorded to the camera’s memory card. A 32 GB card will accommodate roughly 100 minutes of footage and, Matt says, an average day’s shooting for him is usually around 200 minutes. Incidentally, this will typically require four fully-charged battery packs for the 5D Mark II, and batteries will be required for external devices such as the EVF and the external recorder. However, here Matt uses the Sony’s higher-capacity V-lock battery packs – via an adaptor – as a centralised power supply.
For The Record
Matt uses an Atomos Ninja external recorder and this is a 10-bit device with touch screen controls which records both video and audio from the camera’s HDMI output. It encodes in real-time in the visually-lossless Apple ProRes format and records onto removable 2.5-inch hard disk drives.
The Ninja’s touch screen also acts as a monitor and the unit is available with 300, 500 or 750 GB hard disk drives or with 128 and 256 GB solid state drives (SSDs) which don’t have the same shock or vibration concerns as HDDs. The ProRes files are subsequently ready to edit in FinalCut Studio. Incidentally, the new Nikon D4 and D800 D-SLRs offer a ‘clean; uncompressed HDMI feed so recording on the Ninja is direct from sensor to timeline, avoiding any in-camera compression. For most other D-SLRs the HDMI output is a duplicate of the viewfinder so it is necessary to switch the display mode to the image only otherwise the Ninja will record any live view read-outs or superimposed items such as grids or histograms. In some cases, it may be necessary to crop the image to eliminate viewfinder information which may compromise image quality. For broadcast applications, Matt explains, there’s a requirement that the majority of the footage be recorded at 50 Mbps while a small percentage can be at 35 Mbps.
“You can’t key at under 50 Mbps so, for instance, green screen isn’t possible. If you’re doing anything for television, you need an external recorder capable of 50 Mbps and, ideally, 100 Mbps.”
If not using an external recorder for video, most pros will use one for recording audio and, of course, an external stereo microphone is essential even if a D-SLR has built-in stereo pick-ups.
“Audio is a whole other consideration,” says Matt Gormley. “D-SLR sound quality is poor and fitting an external mic relies on a mini-jack which is also easily damaged. You have to record on another medium and use a clapper board to sync. Then you just use the D-SLR’s audio as a guide track.”
Summing up, Matt says, “Cameras will come and go, so it’s really a case of focusing on your ‘infrastructure’ – including the lenses – and getting that right in terms of how it all integrates. To make a D-SLR work effectively as a pro-level HD video camera, you’re going to have to be prepared to invest in the extra equipment and accessories. It can make still photography look like a walk in the park.”
Thanks to Dragon Image for the loan of some of the accessories illustrated in this feature. Visit www.dragonimage.com.au