SPRING has arrived early in Saltaire with an exhibition of 33 pictures by David Hockney entitled The Arrival of Spring.

The five-foot high framed pictures were drawn on the Bradford-born artist's iPad during the latter part of the years he lived in Bridlington, when he painted the Yorkshire Wolds and created the massive Bigger Picture exhibition for London's Royal Academy.

These 33 pictures, to be joined by 16 others later this year, each depict a specific day between January 1 and May 31, 2011. Hockney regards the pictures as part of a single work, each of which encapsulates a moment in time between the changing seasons in East Yorkshire.

Of this seasonal transition Hockney said: "Winter is not black and white; when the snow is there it can be, but it doesn't stay long. Even on dull days there is a lot of colour if you really look."

Hockney maintains that throughout history painters have always used the latest technology available to develop their work. He is not different. The man who in the mid-1970s gave the world joiner-photographs first started sketching little landscapes and domestic interiors on his iPad five years or more ago, dispatching them to his friends around the world.

Of the medium he said: "Turner would have loved it. You can be very, very subtle with transparent layers. The light changes quickly in East Yorkshire, so you have to choose how you want to depict it.

"I realised how fast I can capture it with the iPad, a lot faster than watercolour for example. Simply faster. You can choose a new colour or a new brush more rapidly. You don't have to wait for anything to dry."

These pictures, on display for the first time in the North, celebrate fleeting moments and remind us of the importance of - and the joy we can get from - looking very closely at what we see.

Salts Mill director Robin Silver said: "The display will change when the other 16 pictures arrive, but it will be part of the permanent collection of David's work in Salts Mill."

The venue bought the 49 pictures for an undisclosed sum. Another undisclosed sum was spent converting part of the third floor at the mill into a spacious gallery of grey and white. Some interior gallery walls were removed, others were constructed, new lighting was installed.

"The important thing is that people can come in and look at the pictures for nothing. They can spend as much or as little time as they like looking at them. That's how art should be seen," Robin Silver added.

People And Process: A History of Salts Mill, reveals something of the 133-history of the mill as a state-of-the-art textile manufacturing enterprise.

The centrepiece is a model of Titus Salt's entire 'Palace of Industry' which includes a futuristic subterranean cistern holding 500,000 gallons of rainwater, which was iltered and used in the manufacturing process.

Admission to both exhibitions is free. They are open Wednesday to Sunday, from 10am to 4.30pm .