This is what your documentary will look like in seventy years time

Replay: Old films provide not just a snapshot into the technical abilities of filmmaking in the past, but the cultural attitudes that underpinned the society of the time.

What will your films look like in seventy years time? Probably not like this one. It was shot in the UK's East Midlands in the 1940s and is - quite honestly - shockingly quaint. It's unbelievably dated.

And it's not because of the film quality, which is very shaky-looking black and white with an aspect ratio that's not far off 1:1 by the look of it. You get used to that very quickly.

For me, it's the clipped accent. And - to our ears - the patronising nature of the narration.

To paraphrase: "On Wednesdays, the country people come on their bicycles to the town". It's full of stuff like this and it raises all sorts of questions for me.

Not the least of which is, how can we make judgements about this film when we're not from this time. There will of course be people over seventy watching this. I wonder what they think?

So, what about the future for films we make now?

Old films provide not just a snapshot into the technical abilities of filmmaking in the past, but the cultural attitudes that underpinned the society of the time.

Undoubtedly the way we speak will change. In South London, what used to be a relatively uniform accent when I was growing up is now an amalgam of traditional South London, Asian and Caribbean vocal traits, spoken equally by young people of all backgrounds, and all the richer for it. And it will be different again in - probably - ten years time; never mind fifty.

Fashions, memes, social attitudes... all of these influence our language and our thinking. Any film is just a snapshot of that.

Yes, the medium (black and white film in this case) is part of the message, but the language is as important as the visual content. The accent and the narration shed so much light on contemporary attitudes.

I'm tempted to think that in this age of extremely rapid change, films will date even faster. But will they? With 4K, surely they'll look pretty good in seventy years time?

Except that by then we'll probably be "watching films" by thought transfer. Viewing on a 4K screen will seem very quaint.