I am not sure how relevant this blog will be, but there are lessons to be learned.  I will need to bring a couple of different concepts together to fully explain the issue.

But before I make you read the whole thing, here is a top level summary

1. The creation date of the video (this only applies to the AVCHD structure) is the date of import into Aperture, and not the date the video was actually shot.  This change of date makes it very difficult to place the video into a time sequence relevant to when it was actually shot.  If one uses MP4 file structure, the creation date is correct.

2. On backup of a referenced Aperture library that contains AVCHD files to another drive, the Aperture link to those referenced files on the backup can not be rebuilt, thus permanently losing the connection.  If on the other hand, if one uses MP4 file structure on the Sony camera, the relinking capability of Aperture will work just fine.

The story line.

For personal work, I shoot both stills and video across multiple platforms: D800, GoPro Hero 3, Sony NEX 5N and now Sony alpha 7R.  The most straightforward work flow solution was to import all assets(stills and video) into Aperture(3.5.1).  When I was ready to work on the video, I selected just the video, export the original video file, import it into Final Cut Pro X.   I like storing the original copy of the video in Aperture because I can keyword the video files so they become a bit easier to find.

For stills, I record in RAW on the D800 and Sony and JPEG on the GoPro.  For video I record MP4 on the D800 and GoPro and on the Sony typically AVCHD.

In Aperture, on projects in progress, I keep all the assets as managed which means the stills and videos are stored within the Aperture Library structure.  When a project is completed, I import the whole project into a master library and then relocate all of the digital assets (stills and video) so they are referenced and stored outside of the Aperture library.  This allows me to find the actual original digital file quickly.  In the Aperture methodology, it knows where the digital asset is located not by the name of the drive, but by the UUID (universally unique identifier) of the drive.

The third part of this story is how I backup my digital assets.  I currently use Carbon Copy Cloner (used SuperDuper previously) and simply backup the original copy to a second drive.  Remember that the digital assets are not contained in the Aperture Library, but are referenced files.

The background information has been set.  Over the past month, I have been putting together a single 12 TB drive that will hold all of the personal/family stills from 2001-2014 for my wife.   For this construction, I used recently updated archive copies of the digital assets.  For the largest set, I used CCC, but for three smaller libraries I just did a Finder copy.  Once everything was copied to the new drive, I used the ‘Locate Referenced Files’ and it worked perfectly for all of the stills and about half of the video.  For about half of the video, the ‘Locate Referenced Files’ could not find the referenced filed although it was present on the drive.  In other words, Aperture could not relink to the original reference file.  This is bad news if one ever wants to recover the original video source!

If on the other hand, I kept the video files in an Aperture managed library when I did the copy, everything was copied over properly.  

How relevant is this story.  Well, that is hard to know.  With Aperture fading into the sunset with the rising of Apple Photo, no one outside of Apple knows the video processing capabilities of Photo.  I suspect it will not be able to handle video, but we shall see.  BUT the more practical lesson is when one makes backup drives, it is very important to test the integrity of that drive to serve as a faithful copy of the original.  I had done that testing in the past with stills and it worked perfectly, but had never properly tested the video side of the process.  Fortunately, I was able to generate a work around and solve the problem (just by keeping the AVCHD video as managed rather than referenced).