TWENTY-SIX years ago, when David Hockney was about to leave Britain for Los Angeles, I went to see him at his London studio. A fairly scruffy studio, I remember, somewhere in Notting Hill, though he was already doing well with three one-man shows behind him. At the Royal College of Art, just a few years previously, he had been so poor he had lived in a shed and took baths in the college sink. He had recently gone blond, after seeing a television advert that said: 'Blonds have more fun in life,' and got rid of his National Health specs.

During the interview I went to his lavatory and noticed on the wall a photograph of Denis Law. Heh, I said, I didn't know you were a football fan. 'I'm not,' he said, 'I just like his thighs.' I never used that line in my story. Well, one didn't, back in 1966.

Last week I visited Hockney in his spacious, well-appointed Kensington studio, which he uses only a few days a year. His paintings now sell for more than pounds 1m each, so he can afford such indulgence. He was over here for the Strauss opera Die Frau ohne Schatten, at the Royal Opera House, for which he did the sets. And also to see his mum, now aged 92.

He was looking fit and healthy, his face tanned and hardly lined. An exercise bike was in a corner, on which he'd just done 25 minutes. 'It's taken me over 20 years of living in LA to suddenly take up exercise.' Hair still blond, if not quite as yellow, and, at the age of 55, no sign of it receding. 'People told me in the Sixties I'd end up bald, pouring all that stuff on my hair. But I got subtle at it.'

On his walls, a photo of his mum, posters for various of his shows from the world's leading galleries, some lithographs, a framed copy of his cover for the Bradford telephone directory, plus a few bare bums, male variety. As the world now knows, Mr Hockney is homosexual. He never hid it, anyway, even when it was against the law.

We started with that subject - no messing around these days, but of course these days messing around is what no sensible person does. 'It was 10 years ago when the first of my friends died of Aids. The fact that he was younger than me was, at the time, the really shocking part. Then it happened again and again. I was just counting up the other day and I've lost 25 close friends in New York alone.

'The days when I ran around are over. I did all that 20 years ago. I still know people who are promiscuous. It's their own affair. Young people take risks because they think life is a risk anyway. Sex is a powerful force. People don't ponder it but act upon it. Of course, I've been frightened myself, but if you think about it too much you just drive yourself crazy.

'I have a friend who lives with me, John, who's English and cooks. Other people drift in and out. I keep friendly with most of the boys I've known. But my life these days is organised in a different way. I don't go out to bars any more in LA. I don't like noise. I prefer reading a novel to going out.'

There's another, non-sexual reason for his change of lifestyle, for avoiding parties and openings and gatherings. He is going deaf. 'I first noticed it about 10 years ago. I was giving a seminar in a room not much bigger than this studio. When people at the back started asking questions, I realised I couldn't hear them properly. I went to various experts and they all said the same - I'd lost 20 per cent hearing. Since then it's got worse, slowly but surely. Nothing can be done. It's hereditary. My father went deaf. My sister's deaf. I can talk to you now, face to face, but if anyone was chattering in the background, I couldn't do it.'

He wears a hearing aid in each ear. Alas, that morning his designer aids packed up and he was forced to use the old-fashioned flesh- coloured sort. His special ones, made in LA, are in blue and red. 'I don't consider myself vain. I just think coloured hearing aids look more sporting.'

There is a theory that loss of sight can improve your hearing. I wondered if it worked in reverse. 'I think that's happened to me, but it's hard to prove. Only an artist would be aware of it. I do feel my sense of spatial vision has been sharpened by my loss of hearing.'

During the past 10 years, art experts have commented on his apparent retreat from pure painting, fearing he might have had an artistic block. He denies it. 'I've simply been working out other things.' These have included photography, using Polaroids pieced together; and faxes, sending shapes round the world; and, of course, his set designs for operas.

Looking back, he thinks that perhaps it was not just a matter of trying new things but a side-effect of his deafness. 'I have become fascinated by shapes that transform themselves, illusions behind a flat plane. Both photography and theatre are about illusions, moving between surfaces and what is happening behind. Perhaps I have been stimulated by my deafness to look for more visual excitements.'

He has now returned to painting and his paintings, in turn, seem to have been influenced by his set designs, full of overlapping shapes and textures. The Strauss opera was his first for Covent Garden. There were only five performances yet his work took him seven months. At his home in LA he built a miniature stage, painted the sets, used puppets in place of the singers, turned up the volume really loud on his CD, then made a video of the whole opera lasting four hours.

'Whatever the price of your seat, it should have cost double when you consider the work that goes into an opera. I'm paid nothing, really, in comparison with my paintings, but I love it. I think the theatre world is far less corrupt than the art world. You have craftsmen in the theatre, wig makers, set painters, who love their work and are not in it for the money.'

His love of opera started in Bradford. Every Saturday night his dad used to take him and his younger brother, John, to the Alhambra. 'Mostly it was music-hall stuff, dog acts and jugglers, which my dad loved, but now and again it would be the Carl Rosa opera. I remember them doing La Boheme and thinking it was absolutely marvellous. The sound was so much better with a 20-piece orchestra, rather than six in the pit for variety shows. My Dad never liked the operas, being tone-deaf, but he put up with it, thinking: 'Oh well, perhaps they'll have a juggler next Saturday night.' '

One of his earliest memories of his dad was when he worked in a grocery store. 'Do you remember the system of wires and pulleys and money would shoot across the shop? My dad was the person who sat at the end of the line, emptying the canisters. When I was little, I thought all the money belonged to him.'

His dad, who later became a clerk, grew rather eccentric. When David first gave him some money, his father went out and bought a load of Russian-made watches which he had seen advertised in the Daily Worker, then gave them away to his friends. He once bought some billboard space and painted on his own anti-smoking and anti- bomb slogans. 'I think my father would really have liked to have been a painter. He did go to classes for a while in the Twenties but gave all that up to support his family. I was once at Glyndebourne and there was an old man there, Harry, whose job was touching up the sets. He had his little room with all his brushes and paints, very sweet, and I thought, that's just what my father would have liked to have done in life.'

His father died 10 years ago. His mother, Laura, has since moved in with David's sister, Margaret, in Bridlington, in a house Margaret shares with a woman friend called Ken. Margaret used to be a nurse but is now a herbalist.

'I love going to Bridlington. It's absolutely unchanged. When I first moved to LA I didn't come home very often, but since my mother hasn't been so good I'm here regularly. She's been digging out some drawings I did at school, kids I drew in the street, some nudes I did to get into the Royal College. She's like all mothers. I bet your mother kept your cuttings. I was quite impressed by them, really. I could see in them things that came out later.'

What did she think when you came out? 'There was no coming out. From the earliest days, I took boyfriends home. They were always accepted. All my family are very sweet people.' One brother, formerly Lord Mayor of Bradford, is an accountant, married with four children, and handles all David's affairs. 'I still feel totally English and have never applied for US citizenship. They probably wouldn't have me, anyway. I'm not respectable enough.'

'Oh, come on, you're now middle- aged, one of the greatest living artists, White House invites, etc.'

'No, I'm not respectable. I have taken drugs. If anyone said I wasn't respectable, I'd never sue. In fact, I'd never sue whatever people said about me. LA suits me. I'm settled there. I miss pickled onions, but that's about all. My brother sends me any good bits in the Bradford Argus by fax, so I keep in touch.'

He'll probably leave his collection of photographs to the National Museum of Photography in Bradford, but has not decided about his paintings. He takes no commissions any more and does no portraits. 'I tend to keep most things. If I think it's terrible, I don't want it seen. If it's really good, I want to keep it.'

He thinks pounds 1m for a Hockney is ridiculous. 'Not that I've ever got that. Money doesn't mean much to me. I've always felt rich. I do what I want, all day long. That's being rich.' He is contemplating another opera, probably Parsifal with Placido Domingo, but has not signed anything yet. 'Friends tell me I should do the Ring - while I can still hear it.'

Isn't it an artistic waste, in a way, spending seven months on, say, half a dozen sets, doing the designs for others to paint in, and then they are all destroyed when the show finishes? 'Opera is ephemeral, for the artist or the singer. It only has four hours of existence, then it's gone for ever. But to me, it's worth it. I saw all the performances at Covent Garden. That's what I did it for. My own pleasure.'

'Have you still got paintings in your head, waiting to be done?.'

'I have nothing in my head. Paintings are not ideas. It's only when I'm making a painting that I know what I'm doing. I follow my intuition, trying not to rush things. I might do some sculpture one day. All I've done so far is an aquarium and some bits and pieces for my garden.'

I asked if he was a draughtsman rather than an artist, and we were getting into that when a fax started coming through. He seemed willing to discuss his work, or any other topic, loving new ideas, new inventions. Twenty-six years ago he appeared rather brittle and elliptical. Now he comes across as unaffected, natural, at ease, his Bradford accent still intact. The fax was from his house in LA. It showed two miniature dachshunds and a scrawled message saying: 'Come home soon.' He studied the fax carefully, looking rather puzzled.

His two dogs are called Stanley, after Stan Laurel, his dad's favourite star, and Boodgie, which means nothing, just baby talk. 'I do miss them very much. As I don't go out much, they are my constant companions. They sit and watch me paint and never object when I have my music on at full volume.'

Isn't there something a bit sad and pathetic about people who put too much affection into animals? 'I think there's something sad about people who don't love animals. I get friends coming to my house, and when they see my dogs all they worry about is the dogs pissing and shitting. Sixty years ago that wouldn't have happened. Even people in urban areas grew up with animals. That's all gone now.

'I'll tell you something interesting. Dogs don't recognise themselves. I did a video of mine, which I played back to them, and they couldn't see themselves.' But dogs don't use mirrors, so how can they know what they look like? 'Ah, but Stanley should know what Boodgie looks like, shouldn't he, but he didn't recognise him. I suppose dogs work on smell, not sight. But it made me ponder the nature of seeing. We think we see people, when we look at a painting or the television, but we don't. We see patterns, abstractions, which we have learnt to think of as shapes. Have you noticed how sound has got better in the last 30 years while vision has stood still?'

He stood up, studying his fax. Sitting down, his face and voice had made him look young; now his body seemed older, his shoulders slightly rounded, with the suggestion of a stoop. He was wearing a red tie, blue pullover, green shirt and pinstriped baggy trousers.

'It's not Stanley and Boodgie,' he exclaimed. 'It's just a photograph of two similar dogs, torn from a newspaper. No wonder I didn't recognise them. Phew.'

He treats his dogs like the children he has never had. 'I could not have had any, but I can see the deep satisfaction in making another human being. My mother had five. She's been more creative than me.'

(Photograph omitted)