Here's a (transcoded) clip showing the kind of under-exposure that I'm seeing with my contourhd. This is in Eye, Suffolk today at around mid-day - cloudy but bright conditions. The picture is exposed for the sky sections, leaving the foreground underexposed.
Eye link
[edit: I've just noticed that as I make the right turn at the bank, the buildings fill the screen and the brightness increases. A few yards later, the sky is present again and you can see the foreground darken again in steps of about a second each]
I rigged up a handlebar bracket from one I use for winter torches.
Bracket
Overall, I'm in two minds about this unit. I'm not sure if I was just expecting more than it delivered. I thought I would be getting image quality on a par with a cheapo bottom end HD camera such as the Medion unit.
View: http://www.youtube.com/watch?v=I0eDEB1p9Jc
i.e. the price of the Contourhd reflecting low end mass market components such as those in the Medion being repackaged or redesigned in an expensive specialist case. It is, however nowhere near as good as that but it is clearly much better than sd.
I did look at the sample Contourhd videos before buying and I have to say the image quality of those did look better than what I'm getting. The vholdr forum does have a disgruntled rower who is complaining about the exposure issue (exposed sky, underexposed boat and rowers).
Overall, the exposure setting is annoying, the edge focus is not good and it also takes a couple of seconds to adjust to changes in lighting conditions. It is however, great fun.
I'll see if I can rig up the Medion on a bracket and post the results - it's not a practical alternative as it is a flip screen unit and only works unfolded.
Edit: Ok, here's two simultaneous recordings - the Medion is hand-held so riding one-handed, it's all a bit wobbly. The shady lane is not affected that much by any sky exposure issues but the Medion is clearly brighter and sharper, albeit with less field of view. Files are unedited.
Contourhd
Medion
John