On Saturday, I took a photo of a man in a racist t-shirt attending the Armed Forces Day parade in Romford. I spotted him at the very end of the proceedings, by the roundabout, mingling with the dignitaries bringing up the rear. I couldn't quite believe that he was openly displaying a message of hate in such a public place and at such a commemorative event.
As he moved off towards the town hall I had one chance to grab a decent photo, so pointed and clicked and hoped for the best. Checking afterwards I was relieved the image was focused, and that the man had turned towards me just enough for the slogan on his t-shirt to be readable. I could so very easily have captured nothing of any interest at all, whereas instead I had his innermost thoughts across his chest.
In even more of a fluke, immediately over the man's shoulder was the Mayor of Havering, in ceremonial garb. She was preceded by a flunky with the council mace, adding full-on civic theatricals, and in the background were three policemen, seemingly looking on. I retained all three aspects of the tableau - citizen, government and state - and cropped the photo down.
I chose not to circulate the photo on its own, I made it part three of a triptych, to emphasise the reputability of the event at which this disreputable act had occurred. But when I pressed the button to tweet all three, I had no idea of the chain of events about to be set in train.
A journalist from Buzzfeed was first, asking if it would be possible for me to tweet just the t-shirt photo on its own. I replied that I deliberately hadn't done, but that he could (with due attribution), and he duly did. That set off a busy Saturday, with huge waves of notifications firing in on my Twitter feed all day, as a reaction to his tweet, my original tweet, and other variations on a theme.
The stir continued throughout Sunday, the reaction generally one of horror, or of amusement at the man's half-shaved hairstyle. Shares were in the tens of thousands, and I was starting to be followed on Twitter by some unexpectedly important people, many of them journalists who must have thought I usually originated this kind of thing.
The Guardian was the first of the national media to take notice. They'd noticed an upsurge of racist incidents across the country since the result of the referendum was announced, and the Buzzfeed tweet was one of several used to illustrate the point in an article published online on Sunday evening.
On Monday morning, now in Norfolk, I woke to find my Dad had left a copy of the Guardian open on the dining table. On page 10 was the same article from the night before, but now with a single illustrative photo, which was mine. Blimey, I thought. And then I read the caption.
My image had been described only as "a photograph circulated on Twitter", despite the paper having made clear online they knew exactly where it came from. I've since emailed the picture desk asking how and why this lack of attribution happened, but have yet to be dignified with a reply. If you are reading this at the Guardian, hi, I'm abjectly unimpressed.
But one appearance in the media was sufficient for lots of the rest of the media to take notice, and I started to receive direct requests from elsewhere for permission to use the photo. Channel 5 were first, then the Associated Press, the Mirror, CNBC, NBC, Channel 4 and eventually the BBC.
I could have said no, I could have said pay me money, or I could have said go on then, so long as you attribute the photograph appropriately. I chose the latter path, because it's surely better for this kind of racism to be seen than unseen, in this case to a vast worldwide audience.
Allowing the AP to circulate the photo sent it all around the world, to Canada, South Africa and India and all points inbetween. It also arrived in the newsroom at The Sun, who used it as one of half a dozen examples in an online piece under the headline Racists Shame Britain. And then on Tuesday they used it in the paper.
I must say I never expected to have a photo of mine splashed across two pages in The Sun, immediately alongside the leader comment, surrounded by articles condemning overt racism and in praise of migrants. The tagline "Brave New Dawn" in the top left hand corner looks somewhat unfortunate, but the anti-bigotry tone elsewhere is clear.
This being The Sun, they were of course keen to discover who the half-shaved man was, so asked 'Do you know this vile thug?' and gave a telephone number to ring. And this being The Sun, somebody has since rung and said yes, he's my brother, and they've tracked him down to a flat in Hornchurch.
It's an odd feeling to have made the international news by taking a powerful image that may define how those abroad see Brexit Britain. It's an uncomfortable feeling to have taken a photo that's led to the t-shirt wearer being identified and outed, however unpleasant his emblazoned slogan might be. And whilst I hope that the vast majority of people who've seen the image are duly shocked by it, I worry that for others it may have stoked their feelings even more deeply, potentially making things worse rather than better.
So all I can say is, think before you tweet. It's highly likely nobody outside your immediate circle will ever see the photo you took, but sometimes it spreads far far further than you'd ever think possible.