Advice to prevent movie corruption

Over the last few months, I’ve been in contact with a few dozen people that submitted damaged movies for repair.

I can now share my experience (in fact their experiences, here I’m just an aggregator) and come up with a few recommendations to prevent movies from getting corrupt.
I’ve also recently started my Movie Repair Service, so you may say I’m giving advices that go against my business. But would you trust your doctor if he didn’t not recommend you healthy habits? Probably not.

First and foremost, back-up your movies when possible. This advice is good for any kind of data, but particularly for movies. Due to their huge size, movie files have a higher probability to get damaged, not to mention that long writing operations on an almost full hard disk are more disaster-prone.
Don’t trust storage of any kind. Hard disks die, memory cards are cheesy, USB sticks are fragile, and RAM is … volatile, to say the least.

Half of the repairs come from a storage problem.

Second, always check thoroughly the outcome of your work.
Imagine a simple workflow: Capture in DV, editing with iMovie, Export to iDVD, Authoring of DVD.
Rule of the thumb: Keep all files generated in earlier workflow steps until you have double checked the final product.

By checking I mean watching every second of the movie, on the device it’s intended to go (if it’s DVD, use your living room DVD player, not computer DVD software).
Sometimes a step fails silently and you don’t notice until it’s too late. For instance, it’s common to loose audio or to experiment video freeze several minutes into your DVD. Just because something went wrong during the conversion and iDVD didn’t show any alert message. If you have kept your files, you are safe and you can retry the failed operation. If not, everything is lost.

Third, be careful with live recording. Live recording, ranging from poor man’s webcam to high-end professional, can go wrong. One day it’s battery, the other day it’s software that hangs, or a cable that gets accidently unplugged, or hard disk choosing the worst possible moment to fill, whatever. You end up with a truncated file, with the index missing. Because index is stored in memory, waiting end of recording to be written, it is lost.
Unless someone comes up with a safe recording software (ie writing the index in real time) this will keep happening. This is a nice product idea, by the way.

Finally, the usual suspect: the Panasonic HVX-200 / Firestore combo. I have no statistical evidence here, but I can tell you that I’ve already repaired many movies recorded with this set-up. Take precautions, handle everything with care, or you will soon need my services.