“Is this typical of what you’d eat on a Saturday?” asks Bob Cook, Firefish’s director of innovation. There’s no hint of judgement in his voice, but I still feel self conscious. Cook had just reeled off everything I ate that day. And it was a lot.

Saturday 29 January began with a coffee at 7am, followed by a salmon and cream cheese bagel an hour later, a sandwich and a box of mini chocolate eclairs two hours after that, then on to a double burger and fries in the evening and a cake and coffee an hour before bedtime. “You don’t get many of your five-a-day,” Cook says.

He knew what I’d eaten without me saying, because that had been the weekend I spent as a lifelogger, wearing around my neck a lightweight digital camera that takes a picture every seven seconds from morning until night. The result is a jerky time-lapse video of my life, made up of about 25,000 photos.

Cook reassures me that he’s not there to criticise my intake, merely to talk to me about my eating habits to find out why I reach for a box of eclairs rather than an apple or banana when I fancy a snack. Perhaps there’s something there for a retail company, or the government even, to find ways of encouraging me to choose the healthier option next time.

Facing up to reality
Until the time came to sit down with Cook and analyse those 72 hours, I’d been entirely at ease with the lifelogging device. It was my life that was on film, not me – the camera was always facing out towards other people. People I encountered while wearing the gadget were intrigued or unnerved to begin with, but they all eventually forgot about it. Except my wife, that is, who objected to what she considered an invasion of her personal space, her home, and rejoiced every night when the camera’s battery gave out.

Perhaps she’d be reassured to know that she featured only briefly in the resulting video. My one constant companion throughout the three days was, as it turned out, my phone.

This was a real surprise to me in reviewing the footage – just how much time I spend looking at my phone, browsing news apps, reading forums, checking Twitter and email. Calls or texts hardly come into it, but it seems whenever I have nothing else to occupy my hands, and sometimes even when I’m conversing with other people face to face, I’m on my phone.

Cook is interested in this too. He wants to know how I view my relationship with my phone. “Clearly, it’s my crutch,” I say. But what else? On my way into work it allows me to get a head start on the day, I explain, which Cook takes as a positive thing. Watching the video of me constantly fiddling with it, one might assume I’m some kind of slave to the device. “The phone sets your agenda, saves you time and helps you get home earlier in the evening,” Cook says.

He probes further the “myriad of roles” the phone plays in my daily life – the sort of observations that might be useful for a technology company. Email, games and reading is about all I can think of, but among the thousands of frames Cook has noticed a handful that show my 15-month-old son and I flicking through photos – him having just learnt that running his finger across the phone’s touchscreen causes the images to move.

In some ways then, Cook says, the phone can be an educational device. There’s also a moment on another day when a friend and I are chatting, both with our phones out. I explain that we were discussing the forthcoming Ridley Scott movie, basing our conversation on information we were looking up on our phones. This might be of interest to a phone manufacturer looking for examples of how their products can enable social interactions, Cook thinks.

My not so boring life
I’m impressed he is able to glean even this much of interest from what to me felt like a fairly mundane few days. But in conversation with Cook it seems this is one of the advantages of using the FishEye camera instead of asking people to fill in a diary, where, deliberately or not, they might exclude what they consider to be the less interesting bits of their day.

The video may not capture everything that’s important in understanding a person’s life, “but I get the narrative of the day and how the different bits fit together,” says Cook. “And in some ways that’s what you’re trying to do with ethnography – you’re trying to see the bits that the respondent thinks are really boring about their lives.”

Best of all, Cook says, “I’ve watched three days of your life in half an hour. I simply can’t do that normally. It’s like a distilled essence of you as a person and your life. You’ve created a data set that I can then watch with whatever filters I need – I can put myself in the role of a beer client, or a food client or a technology client and then a whole set of other stuff about your life becomes important.

“And,” he adds, “I don’t have to rely on you rationalising what your day was like, because I can watch that video and develop my own theory which we can then explore in an interview afterwards to find out how true it is.”

At this point I admit that I may have been over-rationalising somewhat in answering his questions – trying to explain my actions more than I should have. Even so, Cook says the interview is important to add context. Indeed, it seems relying on either the interview or the camera footage alone would be unwise. “The interview is flawed because it plays to your memory, your rationalisation, and your projection of yourself to me,” says Cook. “The FishEye footage is brilliant, but it is open to my interpretation of it, and my making assumptions of it.”

For instance, he says, “If I look at you with a bagel in your hands it may be you had a spare one, or it was someone else’s idea, or you may not even like them. But if I don’t ask you to explain that I come away from the video thinking you’re a big bagel fan. I can draw a lot of conclusions from the video, but I would see it as inherently risky not to have a conversation with you afterwards.”

Non-judgemental
To his credit, many of the assumptions Cook made based on the film were remarkably accurate. Looking at the footage of the Saturday, when I was heading to a stag party in Oxford, he says he could tell I felt uneasy about drinking a can of beer on the train (understandably – it was 10am). He noticed how my friend and I waited until the train emptied out before imbibing, and how even then I kept the can concealed under the table.

Cook suggests I might not have engaged in this behaviour at all had I been being shadowed by a live ethnographer. “The camera doesn’t tut at you,” he says. “If I was accompanying you on the train, you might not have had that beer first thing in the morning because you wouldn’t want to have been seen as Mr Boozy.” I don’t disagree.

The lack of observer effect is particularly useful for behaviour change projects where Cook says the camera can be used “to hold a mirror up to someone’s life” to get them to reappraise bad eating habits, for instance, or early-morning drinking – both pertinent in my case. It’s a credit to the device’s lack of intrusiveness that concerns about what the camera was capturing didn’t play on my mind at the time I was wearing it.

Talking about it afterwards, though, was an entirely different experience. Time for a healthy snack, I think.