The key to good handheld: The horizon line… particularly with CMOS sensors
Okay first, just to get some quick terminology clarified, there are three axes to change the orientation of your camera framing:
- Pan (turning to look left and right)
- Tilt (looking up and down) *As a side note, some people use the word “pan” to describe a tilt. Don’t do that, it makes you sound like a rookie cookie. Or maybe just a producer, ha.
- Roll (making the horizon line rotate, as if laying your head on your own shoulder)
Pan & tilt are no problemo as part of anyone’s camera dynamics repertoire. But there is a huge caveat with roll. That’s because when us humans experience this in real life, our inner ear’s vestibular system does a primo job of conveying to our brains that it’s our head’s orientation that’s changing and not the planet earth’s.
So when a camera uses roll, that offset reaction in our vestibular system isn’t occurring, and in its absence our brain’s initial primordial reaction is that the onscreen world is changing in orientation… which is usually not what the film is intending to convey. Except when you’re faking an earthquake or the 1960s USS Enterprise being hit by a Klingon laser beam. I jest, but those are actually perfect examples of this phenomena– it’s the lack of vestibular system reaction that allows those illusions to occur. Who like totally loves that I used the word “jest”? We totally got some Shakespeare In The Park On The Internet On A Blog goin’ on.
Attention Star Trek nerds: that’s a 3 degree roll of turbulence inflicted on the ship, from the episode “The Corbomite Manuever”… ya know in case you wanna like run calculations on how that would’ve affected the warp drive’s dilithium crystals or whatever. In my defense, I had to wikipedia to find a nice trekkie vocabulary word like “dilithium crystal”. I MEAN IT I’M TELLING THE TRUTH.
So anyway, if you’re trying to give a handheld POV chase shot an energetic, actiony feel, then put in a lot of frenetic pan and tilt, but try to minimize the roll. In a nutshell, the mantra of handheld should be “keep the horizon line straight”.
Though there may be times that you want to induce disorientation, confusion and even nausea in your audience, and that is when you do use roll.
And there’s also an additional factor with roll when shooting with CMOS sensors. Good handheld camera craftsmanship in general is of über-importance due to the sensors’ rolling shutter. To avoid “jello-cam” you have to be firstmost concerned with fast, jittery panning… but lots of fast back & forth roll can also give your footage that jibble jabble gloopy glopple jiggle, as pictured in the framegrabs below:
So here’s a simple solution for minimizing roll: increase the radius of your support points from the camera, ie. maximize the distance between your hands. That way, when your left hand shakes half an inch, it’ll just create a 2 degree change in roll… as opposed to if it was one third the distance, the roll would be about 6 degrees. Here are a couple ways to apply this to your handheld shots:
- If you’re using a rail system, put your handles as far apart as logistically possible.
- You can use a cheap, light tripod with its legs together or a monopod and have one hand at the baseplate and the other as lower down as possible.
For a little more help, you can also use a bubble level on your hot shoe and adjust accordingly during the shot.