04.01.2011 01:00 PM
Canon XF305 Camcorder's Face Detection Feature is Valuable Tool

LOS ANGELES—This particular shoot had a tight turnaround. That's "tight" as in wrap at 2:30 p.m. on a Saturday, deliver with mix and color correction on Sunday morning by 9:30 a.m. It would also have to be shot in HD by one camera operator (me) using minimal lighting. Half-scripted and half music-video, the piece was about five minutes long when finished. It was shot mostly on Steadicam, and I spent the entire shoot backpedalling down hallways, through
Michael Blieden. Photo by Jason Uhrmacher
rooms, and running backwards down stairwells while a celebrity cast ran toward me in complex choreography as they lip-synched a classic rock song.

THE BIG AUTO-FOCUS QUESTION

My camera of choice for this job was the Canon XF305 professional tapeless HD camcorder. Not only does it have auto focus, it also has the kind of face-detection technology I'd seen on digital SLRs. Traditionally speaking, auto-focus is something a professional isn't supposed to use. Anyone reading this may be skeptical. However, let me assure you that I sympathize.

But the truth is that almost secretly, and with some shame, I'd been using autofocus on other cameras for about a year, and getting decent results if I didn't push things or zoom. After testing the XF305, we made a very calculated decision that—given our time constraints and the narrow spaces in which we were working—a lightweight camera system that I could operate alone was the way to go.

The XF305's 18x Canon L-series lens has a great zoom ratio and a dreamy quality, while still being sharp. The face-detection technology would find the "hero" in the shot and—for the most part—follow that person's face and keep it in focus anywhere they went in the frame.

FACE DETECTION REALLY SHINES

We had one very complicated shot where everyone was moving and different singing faces were going in and out of the frame. This demanded that the face-detection software select a different "hero" face three times, as the lead part of the song changed from character to character. I learned how to nudge the camera in subtle ways so that there was actually a bit of give and take between us. As an example, the contrast-based focus system needs a certain amount of light, so when the camera was struggling, we turned up the ambient light in the shot and everything became crystal clear.

Face detection is essentially a virtual assistant, or "digital focus puller," that helps you compose and achieve the look you want when your project has limitations. Without this camera I would have needed a human assistant, but that wasn't possible.

Also, the workflow was awesome with the XF305's native 1920x1080 HD on Compact Flash cards.

Auto-focus and face-detection technology were singly enabling technologies for this shoot. As a DP who has used them successfully, they convinced me to "come out of the closet." I feel that if you're using auto-focus and face-detection strategically, then they're not dirty words for professionals anymore. They've gotten that good. They are tools that allowed me to work the way I wanted and get the job done.

Michael Blieden works for a major late-night network series. He may be contacted at blieden@gmail.com.

For additional information, contact Canon at 800-652-2666 or visit www.usa.canon.com.



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Posted by: Anonymous
Thu, 38-05-2013 07:38 AM Report Comment
Great report. Where can we see the results please. Thanks Ivan




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