TV review: Imagine: Vivian Maier – Who Took Nanny's Pictures? BBC1; Secrets from the Workhouse. ITV

Imagine's film about Vivian Maier, a French nanny who turned herself into a remarkable photographer, began with the tabloid headline reduction of her life: "Mary Poppins with a camera". If you already knew her story, I imagine that might have made you wince a little. If you didn't know her story, it was a mark of how good Jill Nicholls's film was that you winced in retrospect, when the Mary Poppins tag came round again. By then you understood how far short that simplification fell of Maier's captivating and thought-provoking tale, full of sad ironies and fruitful paradoxes.

Maier spent most of her life working as a nanny for prosperous Chicago families, taking photographs assiduously both on and off-duty. With no home of her own she filed them away in rented storage and when she couldn't afford to pay the bills during a period of ill-health a dealer called Roger Gunderson brought five lockers, sight unseen. After the images started to appear on eBay and online blogs devoted to street photography, serious galleries began to get interested and her reputation built. Now vintage prints of her pictures sell for up to $8,000. Gunderson's haul consisted of around 150,000 photographs, though he sold them on for a fraction of their current worth.

Judging from the selection you saw here, Maier had an instinctive eye. Her images had that quality of balanced enigma that lifts great photography beyond the merely documentary. But she also documented a particular moment in American history – the boom of the Fifties – in a way that was alert to the excluded. Using a Rolleiflex camera – perfect for a street photographer because the photographer must look directly downwards and can appear to be engrossed in something else entirely – she captured the poor and lifeworn with startling intimacy (some posed shots suggest she also had a gift for getting people to offer themselves up). And one large question was what she thought she was doing – taking snapshots or making art? One contributor here questioned the selection made of her work, implying that the act of editing is an essential part of what it is to be an artist. But another researcher had come up with pretty strong circumstantial evidence that she'd attended a New York exhibition that included Cartier-Bresson and Doisneau, which suggested that she was knowingly refining her skill.

Her own self-portraits – caught in tessellated mirrors or the ghostly reflection of shop windows – added to the poignancy of a life lived at the fringes of other people's families, and the melancholy of what seemed to be a descent into a more brittle kind of obsession towards the end of her life (it was one of the film's ironies that her discovery was at the hands of people almost as obsessional and marginal as she was). But a strange sense of purity was also one of the film's pleasures, of a talent that strengthened itself and did its work with complete indifference to the audience or the market. Touching, ambiguous and full of arresting images Imagine's film was a fine tribute to her.

Secrets from the Workhouse also throws light on unremarked lives, in this case through the Victorian paperwork that marked the procession of the poor and the sick through the workhouse system. A spin-off from Who Do You Think You Are? (it, too, was made by Wall to Wall Television), this two-part series looks at pre-Welfare State welfare through the family history of Kiera Chaplin, Fern Britton, Brian Cox and Barbara Taylor Bradford. It was a story of very cold-hearted charity indeed, conceived to be punitive and off-putting in the hope that people would find other means of keeping body and soul together. The contemporary echoes of this attitude to the poor could hardly be avoided and, to the programme's credit, weren't.