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View Full Version : Green screen test with iPhone 4S!



Serling
10-02-2012, 11:58 PM
OK, you know how sometimes you just decide to try something really whacky???

I just got the iPhone 4S a couple of weeks ago and was using its camera to take some HD video. I bought an app called "Movie Pro" which allows you to shoot H264 video at more than double the bit rate (48mbits) of the standard camera app (21mbits). At that bit rate, I reasoned, why not see if I could pull a clean key from it?

So I set up a test at work where a couple of my co-workers decided to pose as test subjects for this little experiment (if you're reading this, thanks Chris and Gordy). I shot a few seconds of them standing and moving in front of our "weather wall" but ran into a problem trying to view the video on my PC: the "upgrade" to iOS 6 (if you haven't found out by now) uses an H264 codec that's incompatible with Apple's latest QT Pro release (7.7.2). I only mention this so that if anyone else is having this issue when moving iPhone 4(S) video to a PC, I can clue you in on a fix I used to pull this experiment off.

Per some users on the Apple forum, I downloaded a small (4 MB), freeware app called "Xmedia Recode" from a German developer. I used this app to transcode the iPhone's H264 HD video to Apple ProRes 4:2:2 and then imported the converted file into Avid Media Composer. Using Avid's Spectramatte (my chroma keyer of choice), I was able to pull an insanely clean key from this iPhone video with very little cleanup time spent on it!

I realize this isn't LightWave specific, but I thought it would be cool to share something new I discovered and - hopefully - offered some assistance if you have an i(device) that iOS 6 screwed up. As always, photos follow.

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Hopefully Apple will get an update for QuickTime out soon, then I'll be able to redo the key with native iPhone H264 video. Will keep you posted.

Serling
10-03-2012, 12:02 AM
Oh, there was only one more thing I had to do. It seems the iPhone's camera outputs really saturated color, so I had to do a little color correction and tone down the saturation on the master color channel.

wrightyp100
10-03-2012, 01:58 AM
Good show there. Had a client who wouldn't believe me. At least I know I'm right. Might do some tests with my phone.

Serling
10-03-2012, 02:53 AM
Good show there. Had a client who wouldn't believe me. At least I know I'm right. Might do some tests with my phone.

There is a company that makes a case for the iPhone with tripod mounting screws for both horizontal and vertical mounting. I'm thinking it could be useful in the field in a pinch. :)

gerry_g
10-05-2012, 11:34 AM
Getting stuff into premier ok from mine in OS6 and can output from there in pro res 422 so no problem, also you are going to wish you had gone for the iPhone5 cuz stabilisation is night and to the 4s

Serling
10-05-2012, 12:28 PM
Are you using QT 7.6 or 7.7 on your system?

gerry_g
10-05-2012, 01:41 PM
sorry, I'm on a Mac and I'm running SnowLeopard 10.6.8 with Quicktime 10 64bit with Final Cut Pro 7.0.3 and Adobe Premier Pro And After Effects CS6, I can open anything anywhere even prevue it in bridge (badly I might add) I believe things are not quite so hot on the Windows side with regards to QT should have been clearer apologies

Verlon
10-13-2012, 06:51 PM
1. I looked at MoviePro, but went with Filmic Pro 2 with similar features but a killer UI (at least for me). In bright light, the phone does make a nice video. Laws of physics, of course, come into play during low light shots. You can up the bit rate, shoot 1080p60, lock focus, aperture, and white balance easily.

2. I would LOVE to be able to control a "real" camcorder like this from an iPad (same price as an HD field moniter with more pixels, and touch screen, AND its a nice tablet).

3. Give a look at CamRanger for DSLR shooting. Also, OnOne Camera's DSLR remote (less money, but requires a laptop).