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Old Feb 07, 2011, 09:33 PM
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Dance the skies...
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United States, MA, Walpole
Joined Dec 2003
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Quote:
Originally Posted by mclarkson View Post
Some footage from a quick flight with mine:
http://vimeo.com/19651185

I am getting a big difference in color balance between the center of the image and the border, as well as some visible vignetting. I'm attaching a screen grab of what should be a fairly homogeneous landscape. It was a mostly cloudly/overcast day, so the lighting is pretty even.

When you look at samples from different areas in the frame, however, there's a big difference. I'm also seeing a difference is sharpness between the center and the rest of the frame.
What you are getting is pretty much the name of the game with this inexpensive camera, but if you look at the latest FlyCamOneHD, it has the same problems, is much bigger, much heavier, and costs $170. Yes, it is also more versatile, but in terms of picture quality, I can't see any difference from our HD key cam. So here's the deal...

The lens is cheap, it has vignetting on the right/left edges and all four corners. Also the focal plane is not flat, so the right/left edges and all four corners, which are much further from the lens axis, have a slightly different focus from the center. If you focus the center perfectly, the edges and corners will be slightly out. If you focus the edges and corners perfectly, the center will be slightly out. A few of the cameras seem to also have the CMOS sensor array not bottomed out flat in the lens module, so it is not perpendicular to the lens axis like it should be, and the focus in not consistently the same across the entire frame for that reason as well. I had one and just exchanged it, but fortunately there seem to be few with that issue.

<EDIT> Much/most of the edge and corner color change and darkening due to lens vignetting can be corrected by post-processing with certain editors,
such as shown here. Also more discussion of color issues here and here. Also, the camera case could be blocking some light entering the lens causing increased vignetting, such as discussed here.
<EDIT>

Also, the cameras CMOS sensor is very sensitive to light level, and it seems to not hold the color saturation and/or white balance the same as light level changes. This can result in very noticeable changes in color as you pan the camera, getting more or less sky in the picture, or more/less sun.

SO it is what it is... a $40 HD camera with some drawbacks that might be expected at that price point.

As an aside, I just got a second camera (v2) which has what appears to be the first change in a key circuit component with this camera... the CMOS sensor. Is it any better? Yes and no. It seems to have much less "color hunting" as light level changes, but less sensitivity in low light conditions (more video "noise"). And the vignetting and color changes along the edges is still there.
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Last edited by Tom Frank; Sep 20, 2011 at 10:33 PM. Reason: revised info on the version 2 camera