Here are two versions of one of my laps at RFR.
The first is basically the camera output. In FCP, I set the in and out points, and did an “Export Quicktime Movie” operation, which avoids re-encoding. I assume FCP re-encodes GOPs at the in and out points as necessary.
It’s a 200+ MB file. On my fairly decent lap top (dual core 2 GHz with 2 GB memory) Quicktime 7.4 can’t keep up, and ran at about 20-30 frames/sec (out of 60 frames/sec). On a similar computer (with upgraded graphics capabilities), Quicktime ran about 40 frames/sec, Main Concept’s H.264 plugin for WMP had syntax problems, and the VLC Media Player was near flawless at 40% CPU utilization.
The camera file was 12 Mbps. The output of FCP is slightly above 14 Mbps. I’m not sure what the overhead is. Recoding the head and tail GOPs can’t account for that magnitude of difference.
The second file is quarter HD resolution, with 4 Mbps set as the cap for the H.264 codec. To generate this, I used “Export Using Quicktime Conversion”. Again, FCP has some overhead above the set bit rate, yielding a 4.2 Mbps final rate. The Quicktime player should be able to keep up with this file on most current machines. The file is 82 MB, so download may take a few minutes … or so.
640×360 16:9 59.94 frames/sec 4 Mbps H.264 from Final Cut Pro 2, transcoded from source above
Here’s a quick critique of my driving in this footage:
The Esses: There’s 5 to 10 mph more there. I wasn’t satisfied with the consistency of my line, so I wasn’t ready to find that extra speed. You can just brush the first two curbs (1, 1A). Riding them does bad things, especially when you drop off the end of the second curb into a hole.
Turn 3: Need to go faster, and then it’s possible to keep one position on the wheel and throttle steer from 2 to the entrance of 4.
Sunset Straight into 12: Rather than grabbing forth, I just backed off and waited for the braking zone. I need to practice heel-toe in that car if I’m going to do lots of shifting. For now, I kept the shifts to a minimum just to focus on line. (The synchros are pretty worn, so you really need to do a double clutch heel-toe.) Also, this particular braking zone is so wavy, there’s no sense diving in hard. Esp. with a stiff suspension, it’s hard to keep the tires on the ground, so a long, gradual braking is called for.
Turn 13: I played with two lines. This is the “go deep and rotate hard” line. There’s a “just left of middle until turning down for the apex” line that is worse geometry but makes use of better available grip on the surface. The latter line is more of a racing line. Not sure which is a faster qualifying line. (telemetry, telemetry, telemetry).
Turn 15: Same gearing comment as Sunset.
Turn 15A: There’s more grip available than I’m using.
Horse Shoe: Again, more grip available than I’m using. There are a couple lines I played with. “Ride the rim, then dive to apex”, and “double apex with a diamond”. This lap has a line kinda in between. Pick one, dude! The double apex made some instructors nervous, because it’s not the “school line”, and I could have easily taken the line from a couple guys (and have been sent home). Not sure which is the better qual line because I don’t really know how many g’s I can pull at the turn in, other than “a lot more than I did on that lap”.
Turn 23: Not a bad line that lap. Struggled with this corner. It’s a much faster corner than I took it, but, like the Esses, I was holding back until I got precision and consistency. It’s kinda like 6 at Laguna in that there’s a real sweet spot. The sweet spot isn’t as narrow as Laguna’s 6, but still, you want to be sure you can nail it before trying to push the limit.
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