the automatic filmmaker

The iPhone 3GS feature that I was most excited about was video. The very first thing I did when I got my phone was shoot Technologic Overkill, so I could put the video camera through it's paces. In the process I discovered quite a few useful bits information about how the video works. Here is random list of that information:

• The video quality is surprisingly good for a cameraphone. In bright daylight the camera performs excellently. Like most small video cameras, it performs worse in low light. The iPhone will automatically lower the framerate in low light to compensate. The Frame rate will not go lower than 15fps
• The iPhone shoots 640x480 at 30 frames per second. It records to the h264 codec at about 3700 kilobits per second. This equates to roughly 28 megabytes per minute. That's not too shabby. Audio is recorded in Mono at 44.1 khz using the AAC codec.
• Compression artifacting is not very prevalent in good lighting. I think this is where a device like iPhone shines over other small video cameras. It has a very good CPU comparably, which allows for higher quality compression.
• You can select your focus point in video mode by tapping, but only when you are not recording. When you begin recording focus is locked to the point you chose. This means you cannot rack focus while recording. This is a small gripe, but if you consider most tiny video cameras are fixed focus, it is still a big improvment.
• Close focus is the same as in still mode -- 10cm. This is a great feature. When you are filming at a macro distance you can achieve a pretty decent shallow depth of field look.
• Where you tap on the screen also 'guides' the exposure of the video. However, as opposed to focus, exposure remains on 'auto'. If your scene changes enough the exposure will automatically compensate.
• The video works very nicely in iMovie, which is expected. One thing I noticed is that you do not have to convert the video to use the slow and fast motion feature. The codec Apple uses is already suitable for that.
• The "Jelly" effect that most small video cameras exhibit is prevalent in the 3GS. This is due to a rolling shutter.

Here is a short video illustrating some of these points.

iPhone Friendly Youtube Link.

One thing I keep thinking about is how the iPhone 3GS video compares to my Flip MinoHD. In resolution, the Mino beats iPhone hands down -- the iPhone is not HD. However, the other features of the iPhone 3GS might just compensate for its lack of HD. Let's compare and contrast:

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