Twitter is still such a small world. Mostly, it’s the early adopters. @DavidPogue and @StephenFry scroll across my Twhirl panel. @LanceUlanoff reports from a trip to Google and @ScottMonty takes questions with Alan Mullaly at Ford.

A couple of weeks ago, @TateShots twittered their friends for questions to be put to Mr. Hockney. I’ve always been intrigued by the mosaic pictures. Recently, shooting a panoramic flash header, I wondered about Hockney’s technique  - how did he compress space without appearing to use a long lens?

Here’s David Hockney’s answer to my question:

[Reading] ‘How did you shoot your mosaic series?  From a fixed position, or moving around, changing focal lengths?’

I’m assuming [Hal is] talking about Pear Blossom Highway, which was – it looks as though it’s a view from one point, but not one of the photographs was taken from that viewpoint.  I moved everywhere, and in every direction, but I had to start piecing it together while I was out there, otherwise I wouldn’t have known what to take next.

Actually, I was thinking about Place Furstenburg, but Pearblossum Highway is good, too. See the full Q&A on video (just four minutes long) on TateShots #20.

Twitter is still a toddler in social media, but it is growing up fast. The Tate is ahead of the curve, but clearly demonstrating nuts-and-bolts social marketing that promotes interaction, discussion and engagement.

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