FCP5 export to HDV 1080i60
 

I have completed a couple of small projects in FCP5 and I want to export my result to a full quality HDV file in the same format as the original capture - mainly for archiving purposes and if I ever want to use the work again in another project. I am using footage from a Sony FX1.

As a test I tried to export an unchanged, original capture clip on my sequence timeline to see if I would get a similar resulting file after the export.

In FCP5, I used the simple method of export quicktime movie - with the defaults for HDV - 1080i60:

The options were:
Setting:HDV - 1080i60
Include: Audio and Video
Markers:None
Recompress All Frames (unchecked)
Make Movie Self-Contained (Checked)

It is very fast as I had hoped since no compressing should be happening.

I can re-import the new clip back into my timeline fine and no re-rendering is needed on it so I know the format is good but there is a slight difference in the data sizes and data rates when I look at the Movie Info using Quicktime 7.

Hera are the differences in Export vs. Original File (everything else looks identical besides of course the names and locations of the files). I also get the same exact results whether I check the Make Movie Self-Contained option or not.

Original
Data Size 256.39 MB
Data Rate 26549.83 kbits/sec

Export
Data Size 256.26 MB
Data Rate 26536.47 kbits/sec

The differences are minor and I am probably not going to worry about it but does anyone know why the export would have changed these amounts a little bit? Or is there something I should be doing differently?