With recent advancements in CMOS (complementary metal oxide semiconductor) sensor technology, DSLR (digital single-lens reflex) cameras now allow video producers to record 1080p HD video. Canon’s EOS 5D Mark III is one of many DSLRs representing the convergence of still photography and motion video in one device. As DSLRs continue to price out below the comparable cost of a prosumer camcorder, video producers face the decision of which device to purchase that will best match their production needs.
DSLRs offer superior shallow depth of field and low-light sensitivity for recording video, achieved through the combination of a large image sensor and a lens with a wide aperture. Note: Shallow depth of field (SDF) means that a select field of view is in focus while other elements in the foreground and background remain out of focus. The resulting ‘soft’ image is typical of a cinematic look and feel and is ideal for planned production shots. The down side to using a DSLR with SDF is constantly having to re-focus to maintain clarity in event type recordings where the action is unpredictable and continually changing. Tip: Analyze your shots, determine focal points and select equipment that will record the appropriate depth of field for your production.
While lacking professional XLR audio inputs found on prosumer camcorders, the latest generation of DSLRs accepts an external audio signal via a 3.5 mm stereo mic input. The workflow involves recording the audio separately with an external digital audio recorder such as the Zoom H6n which is powered and operated separately from the camera. Tip: Analyze your need to capture clean professional audio. If you value high-end audio but want the shallow depth of field and low light sensitivity of a DSLR, record audio separately using an XLR digital audio device and then sync the audio in post-production. Make sure you have the necessary number of audio inputs on your device to capture multiple sound sources (example, two XLR inputs for a two person interview).
Additional features common to prosumer camcorders that are often not found on DSLRs include:
(1) Ability to monitor audio.
(2) Ability to manually set audio levels.
(3) An electronic viewfinder for clear viewing in bright sunlight.
(4) An articulated LCD screen for different camera positions.
(5) A power zoom mechanism for smooth optical zoom operation.
(6) Built-in neutral density filters.
(7) Live HDMI or component video output.
(8) Peaking and zebra patterns to assist with exposure and manual focus pulls (manually changing focus during a shot). Peaking shows areas of greatest sharpness. Zebra patterns show areas between 80% and 90% of maximum exposure.
Ergonomics and stability are a concern when using DSLRs to record handheld fast action video. Rolling shutter artifacts occur in fast motion recordings due to the camera’s inability to write data fast enough with horizontal frame scans. Often called the Jellocam effect, there is a temporal difference between the time that the top of a frame is recorded and the time that the bottom of the frame is recorded. If the subject (or camera) moves horizontally during a shot, the video will appear to bend. While prosumer camcorders offer grips, shoulder pads and image stabilization to help compensate for handheld video movement, DSLRs with un-stabilized lenses, paired with rolling shutter, can create distorted effects.
To recap, with their larger image sensors, DSLRs offer a narrower depth of field and allow videographers to isolate a subject, giving the video a cinematic look and feel. But when compared to prosumer camcorders, DSLRs are limited in their video recording features and capabilities. Carefully weigh your production needs (and budget) before purchasing equipment. Tip: Be aware of how much media a DSLR can capture at a given resolution and frame rate. Factor in costs for additional accessories – tripod, microphone, cables, lights, lens filters, etc.