Zenzie Tinker has never experienced “just another day at the office”. As a freelance conservator for UK museums and institutions, her work is rarely predictable. Monday might be spent painstakingly repairing an 18th-century curtain from the bed of a stately home, Tuesday attempting to blend a dye to exactly match a vintage dress.

It is not a job for the impatient and Tinker’s studio in New England House, Brighton, is an oasis of studious calm. “Every stitch is a decision,” says the neat, petite brunette.

Although it is often equated with restoration, conservation does not involve the replacement of any missing elements. Tinker works behind-thescenes, strengthening and preserving the life of an object so it can go on being worn, used or displayed.

Shelves contain folders of dye recipes and plastic boxes stuffed with swathes of fabrics – some just dozens of variations on beige – and strange machinery to roll tapestries. The huge tables are covered with current projects, covered over again with paper to protect them from light and dust.

One of these is the famous green silk dress worn by actress Keira Knightley in 2007 film Atonement, which Tinker has been tasked with repairing before it goes on display as part of the V&A museum’s forthcoming Hollywood Costume exhibition.

“It’s proving a bit of a nightmare,” she sighs. Stage and film costumes are not built to last and the dress’s spaghetti straps and bodice are showing signs of wear.

Tinker has spent hours mixing up a dye to the dress’s exact colour, which she will use to colour net to bolster the inside of the bodice.

“Dyeing can be really frustrating. We’ll sometimes do ten dye sheets to get one colour.

I keep them all for reference and when I look at a recipe I can remember the object. You get a visual prompt and can remember them exactly and I’ve been doing this for 25 years!”

Nonetheless, the V&A has decided it will need to position the mannequin in a reclining position to minimise further damage – exhibitions often tour for up to four years.

Tinker enjoys the connection to the past one gets when working on a piece. “Just with this dress I know quite a lot about how it was worn and damaged.” There is a hastily-sewn repair at the front which appears to have been made to preserve the actress’s modesty (the dress is slit to the waist) and the laser-cut patterning on the front has pulled because the skirt is so heavy.

“You become intimately acquainted with sweat patches and wear and tear working on clothes, and when it’s an 18th-century costume for example, I find it fascinating to be that close to someone from the past.”

One of the projects for which Tinker is most renowned is the conservation of a dress worn by Victorian actress Ellen Terry for her famous portrayal of Lady Macbeth in 1888 and immortalised in the portrait by John Singer Sargent.

The project involved some £50,000 of fundraising, 1,300 hours of conservation work and Tinker sewing 1,000 real beetle wings in place on the garment to recreate the emerald gown, whose iridescent wings were designed to look like chainmail and suggest the scales of a serpent.

When you’ve sewn 1,000 beetle wings on by hand, everything else must seem a doddle. “I get a lot of fulfilment from working on objects,” says Tinker with a smile. “It’s creative but it’s very practical. Most conservators are practical people. I’m not an artist, I don’t feel the need to create a beautiful embroidery, but I enjoy repairing them.”

In addition to Knightley’s dress, the studio is also working on an enormous curtain from the state bed at Clandon Park, a National Trust property in Surrey.

“The bed’s quite unusual as all the original upholstery is still there.

We’re supporting damage on the curtains, which is quite challenging because there are lots of different aspects to the treatment.”

She gently picks up an edge, revealing black marks on the paper beneath – silk dust.

“The thread is disintegrating so every time we move it, black dust falls out.”

Tinker has dyed linen to attach behind the tapestry to disguise the threadbare patches and strengthen the piece. The work is expected to take up to 1,000 hours in total. Each segment is tested before being treated and every stage of the process must be noted for future conservators. While Tinker often shakes her head at repairs others have carried out in the past 100 years, she recognises that in another 50 years of progress, someone might be doing exactly the same at her handiwork.

Unless hugely to the detriment of the object, repair work is considered part of its evolving character and preserved along with original features, but everything has to be reversible just in case.

It’s a common misconception that conservators must recreate old dye recipes or use vintage materials for their work – they don’t.

“You can’t predict how they will fade. The dyes we’ve used have been tested not to run or fade. Also, we need to repeat our own recipes and replicate them, so we have to know exactly how to make them.”

Tinker agrees there is a scientific element to her job, but even so, mistakes will happen and she admits beginning work on a piece can be nerve-wracking. “You always have to test and test and test again to avoid disasters but most of us will have had problems with colour runs now and again.”

Formerly employed by the V&A, Tinker set up her own business ten years ago, working originally from her spare room before decamping to larger premises at New England House, which is a hive of artists, makers and specialist businesses.

Her husband Geoffrey Major is also a conservator, who has been working in fine art conservation for more than 35 years and specialises in paper conservation, bespoke museum cabinets and exhibition display mounts.

The bulk of their work is for museums including Brighton Museum, Worthing Museum and those in the capital, National Trust properties and numerous international institutions.

Tinker was the conservator for Brighton Museum’s recent exhibition on Princess Charlotte and worked on the Burmese and Inuit costumes in the museum’s New World galleries.

They also take much smaller commissions however; she recently finished working on a Victorian doll’s dress that had been shredded by the owner’s dog and frequently repairs vintage wedding dresses to be worn again.

Her latest excitement was the discovery of a forgotten chest of couture costumes by renowned 19th-century designer Charles Worth in a private home in Wimbledon, South London.

“No one knew about it and I found them. We’re hoping funding will become available to conserve them, with the idea of putting them on as part of an exhibition.

“To bring something back to life like that is an amazing feeling.”

For more information on Zenzie Tinker and her work, visit www.zenzietinker.co.uk