Friday, May 27, 2011

An old adversary returns.

The price of memories (to paraphrase Wendell Phillips) is eternal vigilance.  At least, that's the case if the memories are kept on videotape.  Way back, when a VTR filled a room, and cost (as memory serves) some 50x the annual salary of the engineer who tended it, one opened a tape box with trepidation.   Yes, readers, videotapes were once 2 inches wides, weighed a ton, and did come in a box.  There were essentially two makes:  Scotch and Memorex, and the latter, especially when not a new tape but, a year or so old, could contain a surprise.

The surprise was called, somewhat unimaginatively, the 'white powder' syndrome.  Said powder would be seen coating the top surface of the wound tape, sometimes loose in the box too.   The powder was a byproduct of chemical degradation in the tape -  assumed to be the 'binder' that held the metal oxide layer onto the polymer base of the tape itself.   At the very least, playback could involve frequent drop-outs of the signal, with possible clogging up of the magnetic heads, which entailed a tedious unthreading, spraying and cleaning of both the head assembly and the various guides and rollers that came into contact with the tape.   At worst, there was no playback at all because so much of the oxide had degraded.   This problem is immortalised in the 'White Powder Christmas' (1) and 'Good King Memorex' Christmas tapes of 1970's BBC VT fame - and although there are reports of similar degradation in some 1" archival tapes, I had thought it consigned to history and (literally) fading memories.   Until this week, that is.

In a fascinating report about the near disappearance and resuscitation of the BBC's Domesday 1986 videodisc, Andy Finney writes of the problems of playing a 1980's videotape (the master for the video sequences).   The laservision discs themselves haven't survived too well, either:  even discounting the problems of sourcing a working BBC-Micro based player to read the material, the discs are liable to delamination, rendering them unplayable.  But all's well that ends well, and there's now a 21st Century version of the Domesday material, on a website of course, accessible to all.  Though I have yet to do the sums, I suspect the entire contents of the original project, data and video, would fit comfortably in the SD card of a smartphone, which would have no problem in playing the lot!

Reading about these problems prompted me to check up on a couple of things, primarily the stock of family home videos (8mm video and VHS-C) and look what I found:

VHS-C (actually JVC brand VHS) from 1988

VHS (Sony brand) 1989

The good news is that both tapes were still playable - and have been hastily digitised - without major problems.  But I can't help thinking this was a close-run thing.  Other brands (TDK, Scotch S-VHS, BASF) from the same era don't show the problem.

Lessons for us all - especially if dealing with originals.
- have a quick check visually.  If in doubt, make safety copies.   But be prepared:  if it's VHS for instance, do you still have a VHS cleaning tape? (2)  VHS is no longer a mainstream standard, who knows what will be around in say 5 years time?
- don't assume that once you've made a digital copy, your archive is safe.  Welcome to the world of 'eternal vigilance' as you tend your hard drives, RAIDS, or digital tapes.


1.  Despite what you might read on the internet, this is the true derivation of 'White Powder' - it's not a drug-related in-joke aimed at famous names.  Not deliberately anyway.  (That all came much later).
2.  Though I always used to reckon that playing a BASF tape was just as good as using a cleaning tape.  BASF tapes had a reputation for being slightly more abrasive, in my experience.

Wednesday, May 11, 2011

May2011 notes: FCP X, NAB snapshots, BBC HD camera list

Despite stated intentions and best endeavours, to nobody's surprise we indulged in flights of fancy, speculation, unfounded rumour and downright guesswork when the wefcpug discussed the almost-announced Final Cut Pro release.  Admittedly, some of the guesswork was pretty intelligent, and the group's collective thanks and respect go to Paul D for his contributions.

On surer ground, Phil presented his own take on how best to prepare.   Simply put, it goes:  fast mac, fast GPU, lots of RAM.   To back this up he drew extensively from a useful paper that Silverado (a US re-seller) have made available for free download – all they ask is your email address.  Kudos to them.   Even better, we agreed with their conclusions.  If you want to know more about hyper-threading of CPUs, Turbo boost and the intriguingly named 'Grand Central Dispatch' this paper is a must.  Or you can plough through the tons of useful info on the Apple developer site (which I was halfway through when the Silverado paper came through – saving a great deal of thinking).

This month's contenders from the useful and free shelves of the apps store were:

Alfred – a simple, unobtrusive apps launcher that has found a permanent home on my macs and persuaded me to retire the Dock
and from Blackmagic the equally simple and useful diskspeed tester.   On my 2010 4-core MacPro this gave some very interesting results:
Firewire 800   64.1 MB/s write, 70.6 MB/s read
Internal SATA (single drive)  58.3MB/s write, 46.2 MB/s read
Two-disc internal RAID  264.3 MB/s write, 259.7 MB/s read

The first two figures are as expected, but the simple RAID result surprised many of us:  they are a brand new install, less than 2% occupied at present – we'll revisit this test in the coming months to see what happens when they've been used a while.
The output of the app is visual and full of the detail you need.  The green ticks and so on in the lower half of the pic (detail lost in fitting into this blog) correspond to the various flavours of video file that might be used (from DV to 2K).

Blackmagic designs also featured in the informal and partial NAB review:

 there's an interesting add-on piece of hardware - the Hyperdeck shuttle -  to record uncompressed material onto SSD via HDMI or HDSDI
 there's a very interesting development in their top-range colour correction suite 'Da Vinci' – with a limited feature-set version (Da Vinci lite?) promised in July as free software.   The idea is presumably to tempt us all to become colourists and upgrade to the paid versions.   Hearty cheers from me at least – a brave piece of marketing which I think will pay off for them.

Left unanswered at the meet were the big questions about FCP to come:  what happens to plug-ins and filters, tape ingest, compatibility with prior versions.   Probably no answers in June, but we'll be meeting again on the 6th on the offchance.

Postscript – Kudos too to the BBC HD commissioning team, and especially Ian Potts, for the recent revisions to their website and the clarity they've brought to the question of which cameras are approved for BBC HD productions.   I'd like to think we in Bristol can claim a little of the credit for this, when one awkward individual took Ian to task at a BBC/Bristol Anchor meeting about the issue.  He promised to take another look at the site, and this is the result.  The current camera list is linked at the top right.  I confidently predict this page will be updated frequently over the year.

Thanks again to Noise Industries for donating the raffle prize - 'Light-Kit' from their plug-ins store.

Thursday, May 05, 2011

Meeting next week - Monday 9th May

What stuff 'tis made of, whereof it is born, I am to learn; 

(Antonio's opening speech, 'Merchant of Venice', Wm Shakespeare) 

Admittedly, the Bard probably didn't have Final Cut Pro X in mind when he put quill to parchment, but the sentiments fit. Antonio goes on to say  

And such a want-wit sadness makes of me, That I have much ado to know myself. 

But we'll have no sadness at the wefcpug meeting next Monday, 9th May, usual place (BBC Bristol), time (assemble from 630pm). Rather we'll echo 'two-headed Janus' (Merchant again) and look back to NAB, forward to the aforesaid FCP and how to prepare.

The webscape is full of (mostly) uninformed speculation, guesswork, uncertainty and doubt, or as Bill S put it: an infinite deal of nothing.   We'll be doing a bit better than that, I hope, with a rundown on this year's new hardware and how it's going to change the way we work.   Let's talk cameras, storage, graphics and yes, tech stuff too!    (Note, the presentations will NOT be in verse, nor in iambic pentameter.   Unless you insist).
I pray you, have in mind where we must meet.