No more lengthy burning sessions, late in the day, no more anxiety over whether “idle copy” has finished sizzling before the next shot. Thanks to its writing speed, the CF card at last allows Cantar to enter Gordon era, Buzz Lightyear for the youngest.
So, it is the end of permanent physical media, stored on shelves. This leads to significant organizational changes for shooting, post production and of course archiving.
We must first acknowledge the inertia of some post-production companies, primarily in the United States, which require DVD-Ram storage because they still use the outdated Fostex DV40 for sync rushes production, instead of a more universal system such as Aaton Indaw. Let’s forget conservative America and stick to modern Europe.
We must explain to production managers that a good 4 GB CF card, for example SanDisk Extreme III 30 Mb/s, is more expensive than a DVD-Ram disc, roughly 6-7 times more, costs over thirty euros VAT, and that 5 to 8 cards are necessary, which will rotate between film set and post-production.
For a TV movie shoot, which means an average of 4 weeks and 25 DVD-Ram, with Just-in-Time syncing, additional cost is hardly important, but media rotation must be carefully planned with production. On an 8-week feature film, where post-production is often delayed, it is best to take around 10 cards.
For overseas of far away shoots, with a few regular footage shipments, and return option, it is best to use additional hard drives which will go back and forth, and to keep one or two backup CF cards. In fact, an external hard drive with enough capacity for all the sound recordings of a film hardly exceeds the price of 4 Flash cards.
As the same card will be used several times during the shoot, you must be absolutely certain that, when it comes back, you can delete it and format it, without jeopardizing the previous day dailies. Nothing looks more like a CF card than another. For this, two things are necessary: a good labelling of the CF card set, and logic mnemonics for the rotations (colours, numbers, related to weekdays or shooting days).
As for us, we believe that the sound mixer should not erase a CF card on the film set; this erasing must be performed by post-production, after making sure they have a perfect copy of the master recording. The CF cards coming back from post must be completely blank of any data. Before he starts writing on the card, the mixer must make sure that it is the case, either by using Cantar Browser mode, or using a computer. However, it is absolutely necessary, on their first use and on each rotation, to format the CF cards with Cantar, guaranteeing a perfect match with it.
We recommend to always deliver the recording of all Cantar tracks, with format of your choice or that of post-production, monophonic, polyphonic, with or without rotation, but without sampling conversion; thanks to CF card writing speed, this will not be a problem, and will respect the basic rule of any backup principle: differentiation of storage locations. Indeed, even if the sound recordings are in Cantar internal disk, you're never safe from disk crashes, lost equipment, theft, sound truck fire...
In the same vein, for proper management of the external HDD (that only DC Audiovisuel systematically provides with Cantar), once back up is done at the end of the day or next morning, it should never be left in the same place as the Cantar, especially at night in the truck. Let’s remind that it is strongly advised not to record in parallel on both drives, internal and external, and that it is better to use Idle Copy on external HDD, which can be coupled during the day with Idle Copy on the CF card.
As it is unwise to perform any post-production process directly from the shooting card, post-production must ensure and check perfect cloning of CF card files. CF card files must first be duplicated in several copies for different storage locations: dailies syncing, editing, secure archiving. For this duplication, a simple computer copy of the files is not enough. The use of a dedicated software copy, which performs a bit-for-bit check or a checksum CRC32 or MD5, is a minimum. Then, it is necessary to ensure the validity of files information, by synchronizing and monitoring all the rushes. Once this quality and validity control performed, post-production erases shooting card content, then passes on a quality report to the sound mixer, and sends back the card to the set, for instance with daily rushes DVDs.
This type of process has already been set up, in the field of digital image, by some post houses in France, such as Duboi in collaboration with Panavision, or Digimage. Quality reports may be available online via a secure web interface. Let’s hope that these post houses will do the same with future Cantar CF cards, and will have the same quality contact with sound mixers than they have with DP.
Finally, we must consider the archiving problem, without going into details about what's worth being archived for the "catalogue", as they say.
With Nagra 5” rolls or Cantar DVD, production, when they deigned to get them back from post house, could for a while store the film elements, physical media which must however be regularly duplicated, for a reasonable cost, otherwise they won’t be usable any more.
For digital files, picture or sound, production must use a provider specialized in this kind of work. The files are then stored on LTO, tried and tested system in computer industrial and tertiary storage, and very common thanks to its versatility. These LTO tapes are copied every five years to overcome magnetic degradation over time. By comparison, the American majors still back up film elements on magnetic perforated tape for sound, and three-coloured film for picture.
For its part, DC Audiovisuel, in an informal and not contractual way, keeps for a period of about six months the sound recordings of all the recorders back from shoots.
Nota: it is necessary to update the Cantar firmware to 2.42 version after replacing DVD burner by the CF caddy.