Technicolor developed a Picture Style for Canon DSLRs, the 'Technicolor CineStyle'. It captures the full dynamic range of camera's sensor by using a Logarithmic color space (Technicolor use a log color space in their in-house work and realised Canon should too). It was developed for the 5D II but also works with the 7D, 60D, 600D etc.
http://www.youtube.com/watch?v=Aa5vtP_o0L4 - Joshua Pines, one of the creators of CineStyle.
They also include a Look-Up-Table (LUT) to convert Log CineStyle to linear color space. However, Kdenlive can't import the LUT. Technicolor say if software can't use LUTs, use gamma correction or better still, manually create a Bézier curve. So I followed online instructions and carefully created a Bézier curve in KdenLive. I also checked the curve works properly by doing a side-by-side comparison between video frames exported from Kdenlive and Photoshop (which can import the Cinestyle LUT indirectly).
Here's the curve: http://dl.dropbox.com/u/2055577/Cinestyle.xml
Place Cinestyle.xml in /home/USERNAME/.kde/share/apps/kdenlive/effects/
To use the curve choose Add Effect -> Custom -> Cinestyle
Hope people find this helpful.