Archiving footage?

[Exact]

Exact,

I have been doing some research on Blu-ray reliability and trying to separate opinion from quantitative data. Could you tell me what this quote is based on?

"However, it's relatively fragile compared to CD & DVD and is highly susceptible to finger marks cause read problems (more than CD or DVD ever was)."

Is that your opinion or from a documented study. Opinion is OK, nothing wrong with that, I just want to know the source.

Best Regards,
Grant

In addition to videography I have a business that deals with media duplication & archiving systems for CD, DVD and Blu-ray. The statement you quote is based on substantial experience over thousands of discs (probably millions of CDs, hundreds of thousands of DVDs - possibly millions, and tens of thousands of Blu-ray).

Is it a documented study as such? No. Is it an opinion formed by looking at lots of discs (good and bad) and systems logs? Yes. It's also personal experience of using the media.

Grease from finger marks gets on to media without you realising it. Grease that was there prior to recording can be seen as a shadow on the recording surface of the disc (as the laser passes over the grease). If the grease was added after recording there is no shadow. Because of the size of the pits and the density of the data it's much easier to damage a Blu-ray disc than DVD, and DVD is much easier to damage than CD.

Re-Writable media (CD-RW, DVD +/- RW and BD-RE) are even worse because they reflect much less of the laser light back in the first place. Get finger grease on a BD-RE disc and you can say good bye to any hope of reliability. Cleaning it can help (assuming it was added post recording) but don't rely on it.

I've never understood why the general public wanted naked media instead of media in caddies, which was much more reliable than naked media will ever be.

 

[Cranky]

I've never understood why the general public wanted naked media instead of media in caddies, which was much more reliable than naked media will ever be.

It is not the general public. It is Sony and Panasonic who ditched caddy from BD spec. The original BD looked very much like PD, but maybe Sony was afraid that people will start using BDs in XDCAM cameras? Dunno. And of course, discs in caddies are more expensive.

 

[ggrantly]

Exact,

Thanks for clarifying what you have experienced. That is exactly why I asked; you have significant real world experience with the media, which has real merit to the list.

This year I have abandoned tape aquisition in favor of both P2 and avchd. Suddenly the quantity of data to backup is going to grow and I can't just throw the DV tapes in a box anymore. My need aren't huge, maybe a TB or two per year, but I'm not to enthused about redundant HDDs.

So given the experience you have, how do you backup your data? If used carefully, do you think Blu-ray is OK?

Grant

 

[Exact]

Exact,

So given the experience you have, how do you backup your data? If used carefully, do you think Blu-ray is OK?

Grant

I was going to write a long post about how I back up - but that may get boring to many people.

Like anything, Blu-ray can work very well as backup media, but don't buy the cheap stuff, get the archival grade media. Never touch the top of the tray in the drive because you will transfer finder grease to the next few discs you put in it. Never touch the recording side of the disc, ever! Pick the disc by the center hole and edges only.

Keep your DVD/BD recorders clean and as dust free as possible. Ever opened your computer? All that dust is in your drives too. It's on the optical lens, it's on the servo focus unit and it's on the greased carriage mechanism too. Once dust settles on the optical lens the recording quality drops, and reading ability is also impaired. Once the grease becomes contaminated it stated to break down or get pushed to the extremes of the lead-screw. One day all your media will start failing at the same place and you won't know why! Don't leave discs in drives over extended periods of time, and don't let discs become too warm.