His film Maratus (about tiny but spectacular dancing Peacock spiders and an arachno-enthusiastic Canberran obsessed with them) took out the top prize at last year's Stronger Than Fiction documentary film festival.

Now he has started up a startup, Heirloom Films, that makes client-commissioned films about Canberra's elders, interviewing them about their lives, so as to preserve their life stories for their loved ones.

A major inspiration for this enterprise came when his grandma, Lesley Cunich, was diagnosed with dementia.

"So this was my personal experience of there being this urgency about getting her stories down," he testifies.

Then as well he was asked to make a film about the work of entertainers who take comedy and music to people in nursing homes. While spending time in those homes he was sensitised "to the wealth of [elderly peoples'] stories that go unrecorded".

His sense of "urgency" about capturing his grandma's stories has materialised, because he is a documentary film maker, in the form of a 15-minute documentary film. The result, a model of the service he offers, you can see it at Heirloom Films' website) has his grandma reminiscing while film and photographs of the period and the people she is reminiscing about are artfully woven into the narrative. So for example as she remembers the tricycle she was given when she was three up comes a photograph of her at three with that new tricycle. With her is a bewildered soft toy koala, not sure how to cope with having this new rival for little Lesley's affections.

Cunich knows that this is very emotional territory that he is venturing into.

He tells how he was approached by Felicity Prideaux and asked to make a documentary about her mother Loas who was then thought to have only about a month to live. Cunich remembers how the old lady although "very weak" was somehow energised by the project and so "she was able to sit up and passionately tell her story, for over an hour".

Later she saw the documentary and was glad to have been able to make it, seeing it as a gift to her daughter. She has since died. Felicity Prideaux tells Simon Cunich that she watches the film again and again and is always finding new things in it, in her mother's expressions, in her voice, in her smiles.

The little documentaries (Cunich says "they can be as short as 10 minutes or as long as 40 minutes - it's all still a work in progress but I don't think anyone is going to want a two-hour epic") are so effective because they give people a visual way of remembering a loved one, of how they looked as they talked.

Although this is a business startup Cunich seems a sensitive and not very capitalist chap and alert to what a very sensitive field it is that Heirloom Films is straying in. The venture is quite new and the expression "work-in-progress" comes up again and again in his discussion of what he's doing. He's very alert to how the documentaries' subjects have never before had this kind of intrusive limelight. His methods must never come out of the paparazzi manual. Instead, having done preparatory homework with families' help, he tries to sit down with "a cup of tea" and gently explain to the subjects what he'd like to do. He always goes to the subjects where they live, and sets up a "mini film studio" (just two cameras) around them.

We have our doubts abut all this. We bombarded him with sceptical thoughts. We wondered if anyone so far has told him (as this columnist would) to buzz off? He laughs that the closest he has come to this is that a woman bought a documentary gift voucher and presented it to her husband whereupon he told her "Come back to me in a few years' time!"

I would tell him to buzz off, I explained because there's surely a danger that when you make a short documentary about someone it neatly tailors the subject. It fits him or her firmly and forever into a frame. It is how henceforth how everyone in the family will think of that person. How likely is it that a 15-minute film, dwelling sentimentally on a subject's nicenesses, will do justice to someone who has lived a long and complex life? What of complete bastards? Will they ever get their docos commissioned? Some children, I nagged (forgetting that I was supposed to be interviewing Cunich and not lecturing him, a tendency that has dogged my whole career in journalism) knowing how flawed dad or mum has been, will never want a 20 minute hagiography of a saint.

Cunich, when at last I let him get a word in edgeways, reports that in making these films he has already encountered two men who have reflected to the camera on what imperfect fathers they've been. So the films don't have to be sugary.

He says too that he doesn't pretend to clients that the documentaries are finite portrayals of entire lives. Rather they are a way that surviving loved ones can always remember how the departed looked and sounded, what expressions used to cross their dear faces.