Cut the Cord with Wireless HD: A Paralinx Review
COW Library : : Helmut Kobler : Cut the Cord with Wireless HD: A Paralinx Review
A few months ago, I started yearning for a way to give my clients a "director's monitor" so they could see what I was shooting without being tethered to my camera by way of a long video cable.
Of course, there have been tools to do this for years, but all of them seemed to have unacceptable compromises for my kind of work and budget. The higher-end solutions from the likes of Boxx and Nebtek were big and expensive. The more affordable solutions, like Teradek's Cube, were smaller, but suffered from delays from a few frames to a few seconds (aka "latency"), couldn't support 1080 resolution effectively, and required using a tablet or computer to receive the signal.
But as I did my research, I noticed there was a quiet revolution going on in the wireless video space, with new products eliminating performance issues like latency, while getting smaller and cheaper. I tracked down two products in particular that seemed to be getting some traction, and got evaluation units of each (the benefits of writing for Creative COW!).
The two units are the Paralinx Arrow, and the Teradek Bolt Pro. Each offers a couple of different models to choose from, but I picked configurations that were different from each other, and appealed to different audiences.
The Arrow is HDMI-only, and least expensive at $1,198 for a single transmitter/receiver package (there's also an Arrow Plus package that's $1,398, which can multicast to up to four receivers at the same time).
The Bolt Pro is about twice as much at $2,490, but you get industry-standard HD-SDI connectors with loop-through. A Bolt Pro transmitter can also broadcast to up to four receivers, and the transmitter features a built-in 60 minute battery so you don't have to worry about powering it in certain scenarios. (Note: you can also get a less expensive Bolt Pro with HDMI connectors, or a non-Pro version without pass-through, multiple receiver functionality or the built in battery).
TESTING THE TERADEK BOLT AND PARALINX ARROW
After trying out the Arrow and Bolt Pro for a couple of weeks, my experience shows them both to be reliable, with similar performance -- ie, the same simple setup and operation, the same signal range, the same bandwidth to carry a high-quality HD image (1920x1080, 4:2:2, 10-bits, up to 60p with 2 channel audio) and the same negligible latency of less than 2 milliseconds.
Regarding signal range, they both advertise a range of about 300 feet when their transmitters and receivers have a line-of-site to each other. I wasn't able to test out the 300 foot range, but did try a 100 foot test in the great outdoors, and could not see any degradation in the HD image being beamed to a 7" SmallHD monitor. (Apparently, when the signal degrades, you'll begin to see artifacts in your image, or will lose the signal altogether. Since artifacts might be hard to spot unless you're really looking for them, I would personally not use either of these units to record an HD signal to a field recorder, expecting that to be my camera master).
I also tested the Bolt and Arrow in my basement, without line of site (ie, around corners and storage boxes) and found they held their signal for the 40 feet of distance I could put between transmitter and receiver. Finally, I walked my camera up 7 stairs and another 10 feet into my backyard. That move finally killed the connection between both the Arrow and Bolt's transmitter/receiver. I guess the elevation change, through a narrow stairwell and doorway, along with the concrete foundation of my house, was enough to muck things up. The good news is that when you lose a signal, both the Arrow and Bolt can re-establish a link automatically once you bring their transmitters and receivers within range. I found it took about 10 seconds for my camera's image to show up again on my monitor.
It's also worth noting that both units showed no vulnerability to interference from other common wireless devices, like Wifi networks and cel phones. You can also run multiple pairs in the same vicinity (for instance, a transmitter/receiver for an A camera, a B camera, a C camera) but you'll need to follow some minor prototcol so they don't interere with each other. First, power up the A camera's transmitter/receiver pair to establish a link, then wait at least 60 seconds before powering up the next pair, and so on. Also, keep the pairs at least a couple of feet away from each other.
At any rate, the Arrow and Bolt's solid real-world performance was certainly enough for plenty of scenarios -- ie, put a handheld, battery-powered monitor in the hands of a nearby director; set up a video village for clients without laying cable, or monitor a camera while it's mounted on a crane/jib/dolly, or in a car.
As I worked with the Arrow and Bolt, I also found another benefit to going wireless, and that's for fine-tuning lighting on a set. I often shoot as a one-man band, without a grip or PA available. When I'm setting up lights, one of the little hassles I endure is adjusting a light, and then running back to my 17" FSI monitor to see how it looks, and then running back to the light for more fine tuning. But with the unique combination of the Flanders and a Bolt or Arrow, I was able to easily move the monitor around with me to each light. Despite its 17" screen, the Flanders is only 6.4 pounds, and can run for hours on a single Anton Bauer Dionic HC battery. Even with an HD receiver and small light stand attached, I can easily lift the whole package with one hand, and carry it over to any corner of the set.
POWER AND MOUNTING
Mounting the Bolt and Arrow is pretty straightforward: you get enough