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An edited version of this appeared in Zerb magazine Autumn 2004....



A learned discussion on broadcast quality – or not.

I was having a potentially spirited discussion the other day with someone on whether DV is broadcast quality, and indeed, whether digital transmission is broadcast quality. In the end we didn't quite manage "spirited" because we've known each other for a long time, are tolerant of differing views and too grown up to come to blows - but it led me to pondering since on the old, old question of "what actually is broadcast quality?" I do have quite strong opinions on the subject, since like many producers, I've spent a good bit of time down the years having "spirited" discussions with engineers about what I could and what I couldn't put on the air. I do have my own standards on what's allowable, and have been know in the past to make and transmit stuff that I thought was well below par. As it happens, though, 16mm reversal Ektachrome with sticky-tape joins and hairs in the gate were thought by BBC Engineering to be perfectly acceptable at the time, even if I didn't.

I'd like to start by trying for a standard which everyone should think acceptable, no matter what their background and axe grinding needs. A lofty ambition, I know, but I think I'm up to it. I hereby propose absolute realism for all the senses as an ideal goal. There you go, pick at that one. Obviously it isn't currently practicable, but it's been part of science fiction for a long time, with a recent high-profile outing as the Matrix. Of course, the social implications of such a thing are immense, with people disappearing off in Albert Square and never coming out - “I'm Not a Celebrity But I Can Come in Anyway” would sweep the ratings. Personally,I have enough trouble with a son who won't stop playing Gameboy. Whatever - you can't do it yet, and that's that, but we can consider the proposition as a genuine standard, I think.

Which is all very well, but we need to take a step backwards in the direction of practicality. Personally, I love IMAX 3D. It's the most immersive visual experience I know, and it's superb. Even I want to reach out and touch the pictures, just like the five year old next to me. I'd love it in my home. In fact, it's perfectly possible to have a tv version of it in the home, scaled down a bit, of course. You just need two HDcams, some filtering and lots of tx bandwidth – no problem at all, we could have it all running in six months. Wow, I've invented a new system which will make me a fortune. Or not.

Surely people will pay anything for the most uncompromised pictures they can have.

No, they won't - so broadcast quality must have some element of compromise in it somewhere. Where?

Actually, the only problem I have with IMAX 3D are the stories. They are always pretty average. And it doesn't matter how high quality the pictures (and as this a cameraman's publication we'll take it that the sound is always just amazing), if the story's no good, it turns out we just aren't interested. I imagine the directors of photography on most Hollywood movies are pretty good stuff to get where they are, but it doesn't matter whether they spend five minutes or a week lighting the next shot - if the script isn't any good our index finger twitches on the remote, and all their work is consigned to the bin.

We can take this the other way - how rubbishy can the pictures be before we'll abandon a good story? Well, if you think about it, quite a long way. If your kids came by a copy of the new not-yet-out-anywhere Harry Potter film on 3rd generation LP VHS would they watch it? Yes. Would you watch it with them - very likely. Come to think of it, I did once - interesting place, Bovingdon market.

Here's a scenario which I give to people on my DV courses. You're at the airport with a VX2000 and the you're the only cameraman for miles. You hear that the next 747 is coming in wheels up with 300 people on board. It's fairly dark and the aeroplane will be quite a way from you. Your training says that if you wind in 18dB of gain and zoom in to 48x on the digital zoom, the pictures definitely won't be broadcast quality. Do you a) go home b) switch in everything you can find to get a major scoop picture. Do you worry that news editors around the world won't pay for your pictures because they aren't broadcast quality? Do you ****.

So perhaps the steps we're making here are taking us towards somewhat of a moving target.

Let's look at the top end. Is 35mm film broadcast quality? Undoubtedly yes, because we've been broadcasting it since the beginning. So it must be as realistic as we can reasonably manage. Well, no. Anyone who has watched one of those behind the scenes at the movies programmes knows that when we look at the behind the scenes video footage, it looks much more like real life than the next bit, the same thing from the actual film. A very large amount of money has been spent trying to make video in tv dramas look like 35mm, even though we know that 35mm isn't as realistic.

Hmmm...

Ok, let's get to the nitty-gritty, the endless bone of contention around here - what about DV, is that broadcast quality? Well, which DV are we talking about? DV is a recording standard, not a camera, and is defined by something called IEC 61834 (not many people know that). The actual digital stuff is not that different from DigiBeta, I'm told by the BBC's top research department expert. But any tape format can be recorded from any camera, and that's what makes the difference. DigiBeta tape decks aren't usually attached to a £300 single chip camera, but DV decks often are. Anyone who has done the tests, and I have - the official BBC ones - knows that the camera makes by far the most difference to perceived quality compared to the tape format. The obvious test is to attach a DV deck to a £40,000 Digibeta camera, and see what comes out. I haven't done this one because my tests were too early on in the DV era, but those who have say they can hardly tell the difference, and then only some of the time. It's not £37,000 worth of difference. Maybe sometimes we want to pay the £37,000, mostly these days we don't - or more likely, can't. A compromise.

But we do generally want something a touch up market from a £300 camera from Dixons, the question is how far? At this point it all becomes pretty subjective – personal opinions all round. And that's actually what broadcast quality is all about in the end, subjective opinions. We look at the screen and make a decision, based on our backgrounds, experience, and axe grinding requirements. Completely and utterly subjective, no scopes or other high tech measuring required. And what do we decide - is the output of a VX2000 broadcast quality?

Yes.

Why?

Because as the producer I say it is.

As simple as that.

Whether or not something is broadcast quality on a given date on a given network on a given programme is decided by those who have the power to make the decision. That's the reality now, and always has been. Anyone else is entitled to their opinion, but it isn't relevant. In the BBC it used to be the engineers until someone worked out that it's the producers who have the budget. Now it's the person who's paying, or their boss, or their boss's boss - and that's right because they are the ones who take the responsibility, and lose their jobs if it doesn't work out. And, nipping quickly back to the original discussion, the same thing applies to digital transmission.

Of course, the decisions they make are based on costs and the market - whether anyone will watch, so really - really,really - it's market forces which decide. Like always.

There endeth the article in it's original longer form - so anyone want to join in?