Canon 5D Avid FCP roundtrip

digitalfilms by Oliver Peters

No, this isn’t the 5D workflow article that you’ve been waiting for. That’s still coming in another couple of weeks. In the meantime, I’ve started on another Canon 5D commercial. This time I’m cutting the project in Avid Media Composer instead of Final Cut Pro. There are a number of reasons, including some recent stability issues I’ve had with FCP. In addition, the creative treatment calls for some nice speed ramp effects. Avid’s FluidMotion is simply a much better slomo technology than anything in Final Cut. So this time, Media Composer is the right tool for the job.

In order to make sure that video levels match what I’m used to with FCP, I’ve been doing some testing of how to roundtrip files back to Final Cut. Ultimately these are web spots, so I want to make sure what I do in Media Composer matches what I do in Final Cut. When I finish editing the spot, there may be a reason to continue in FCP – such as to use Color for grading. That’s another reason to be very sure the images match, regardless of the NLE used.

That’s the dilemma. Avid has always treated video as Rec. 601/709, which means that black and white equal 16 and 235 on a scale of 0-255. This allows headroom and footroom for superwhites and “blacker than black” shadow areas. FCP doesn’t really honor this scale and seems to internally use adjusted levels of 0-235 (my guess), so it makes it tricky whenever you convert clips in and out of QuickTime. Not every QuickTime conversion is equal and you may get level, gamma, saturation and hue shifts depending on where and how the conversion is done and which codec is used. read more...