I bought one a few weeks back. It is simple, seems to work well, reasonable cost. I have the 720p one, there is a 1080p available soon. No wires, completely self contained. Only drag is no audio input except for the internal microphone. I think a small ear piece taped onto the microphone and wired into the audio panel would actually work well. I personally like to hear some of the background airplane noise!

See this thread for a sample.
 
I have the gopro hero wide, works awesome for my motocross racing helmet cam, and some stuff I do at work. It comes with a bunch of mounts for things like roll bars (perfect for the rv-4) and a suction cup mount that at over 250 kph on the fairing of my bike stayed in place. And it's waterproof and the sound quality is better.

The contourhd is better in the fact that it's high def, the slide button is easier to work, and the lens is wide screen, not a fish eye. Also, it will be better suited for me at work since it's black and a smaller frontal profile so I can mount it better to my combat helmet for when I go overseas.
 
Some of these mini-cams will turn a prop arc into 'window blinds' in bright light (high shutter speeds).

Has anyone tested either of these two mentioned vid-cams viewing through the prop? I'd be interested in getting one, but not if they are going to turn the prop arc into an artifact.
 
Prop issue with video

When a propeller is filmed or recorded on video, the RPM of the propeller interacts with the frame rate of the recording device to create an optical illusion of the propeller turning back (or other weird effects sometimes like arcing) and forth at various speeds, depending on the exact ratio of propeller RPM to frame rate. I would suspect that 30 fps would less likely creat that effect than 24 fps. But if you use a cheaper camera phone with 15-24 fps you will definitely get the "western wagon wheel effect".

This illusion normally doesn't happen when the propeller is viewed in person, since the human eye doesn't have a "frame rate." But try looking at a ceiling fan and blink your eyes fast. You'll see a similar effect.

You just need to play around with frame rates when recording and not in post [production].
 
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How are people mounting these on their airplanes? I have a sony CX-100 that is fairly small and great quality. I'm curious the best way to mount it in my RV4.
 
Junglepilot said:
When a propeller is filmed or recorded on video, the RPM of the propeller interacts with the frame rate of the recording device to create an optical illusion of the propeller turning back (or other weird effects sometimes like arcing) and forth at various speeds, depending on the exact ratio of propeller RPM to frame rate. I would suspect that 30 fps would less likely creat that effect than 24 fps. But if you use a cheaper camera phone with 15-24 fps you will definitely get the "western wagon wheel effect".

This illusion normally doesn't happen when the propeller is viewed in person, since the human eye doesn't have a "frame rate." But try looking at a ceiling fan and blink your eyes fast. You'll see a similar effect.

You just need to play around with frame rates when recording and not in post [production].
Click to expand...

Your describing a different, and smaller, problem than the effect I'm referring to here: Flip Mini HD videocam test

This is a completely different from stopped prop effect and is caused by the type of electronic shutter employed in the vidcam. Something to check before you by, in my opinion, if you plan on shooting video through the prop.
 
There are two main sensors types used in todays digital camcorders, CMOS & CCD. Because the designs of the two devices are different, they end up with different approaches to the "shutter" (there is no mechanical shutter any more).

Most of these newer low cost HD camcorders use CMOS sensors as they are less expensive to produce. Unfortunately CMOS sensors & their "shuttering" mechanism are prone to these prop-type artifacts ; and then if the camera has minimal controls, there is no way to overcome them.

If you have some "shutter" control then you might be able to minimize them OR just don't shoot through the prop.

Some Examples:

-Sony Mini-DV TRV-900 camcorder, bought some time ago, has 3 CCD sensors (RGB) & good shutter control.

-Canon HD SDHC HFS-100 camcorder, bought recently, has a single CMOS sensor & good shutter control.

-Small, inexpensive DXG-579V HD SD camcorder, bought recently to experiment with, has a single CMOS sensor & no shutter controls. Expect prop artifacts.
 
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