LEngth of footage for blu-ray disc

[Gabroo Singh]

For a single sided blu-ray disc, how much time can it hold? 1920.x1080 footage from NX5U

[Randall Leong]

It depends on whether your shooting mode is FX (24 Mbps max) or FH (17 Mbps). FX really averages about 21 Mbps (or 15 Mbps for FH). Figure on about 2.5 hours of FX-shot footage or just under 3.5 hours of FH-shot footage (both times are estimates).

[Gabroo Singh]

Thanks for the help.

To get those times, are you dividing the storage space (total gb on blu-ray disc) by the mbps?

[Randall Leong]

Originally Posted by Gabroo Singh

Thanks for the help.

To get those times, are you dividing the storage space (total gb on blu-ray disc) by the mbps?

I added audio and other miscellaneous bitrates to the average video bitrate of the file. The 21 Mbps and 15 Mbps figures apply to just the video bitrate. Then divide the average total bitrate into 25.2GB (or 23.4GiB).

[Perrone Ford]

I don't understand what shooting format has to do with bluray authoring.

[Gabroo Singh]

Originally Posted by Randall Leong

I added audio and other miscellaneous bitrates to the average video bitrate of the file. The 21 Mbps and 15 Mbps figures apply to just the video bitrate. Then divide the average total bitrate into 25.2GB (or 23.4GiB).

Thanks Randall, you've been a major help.

You wouldn't happen to know how long you can squeeze out if you are using 720p/60 from the NX5U, do you?

[Aaron Holmes]

Hi, Gabroo:

You may have this figured out by now, but the resolution and framerate (e.g., 720p60, 1080p24, etc.) don't really figure in how much video you can fit on the disc. It all comes down to the data rate. On your memory card (or FMU, if you have that on your NX5), 720p60 in FX mode will take up the same amount of space for any given period of time as 1080p24 in FX mode will; "FX" is Sony shorthand for 24Mbit/s peak.

Also, as Perrone rightly pointed out, shooting at a given data rate really has nothing to do with the data rate on the disc. Not necessarily, anyway. Frequently, you'll want to (or have to) adjust the data rate of your project to make it fit on the disc or else to minimize the effects of recompression.

Most of my Blu-ray programs (home videos) are an hour or less in length, meaning that I can take the 720p60 FX-mode sources from my NX5 and recompress my project at a much higher rate of 35Mbit/s and it will still fit easily on a one-sided Blu-ray. This is nice, because in general, recompression (implicit in most NLEs) is a damaging process, and boosting the data rate to the maximum that will fit on the target media often minimizes the appearance of new compression artifacts.

Enjoy the NX5! Great cam, IMO.

Best,
Aaron