A 75 ml glass bottle with a ribbed black screw cap, labelled OIL COLOUR at the top, Varnishes on the grey band and ARTISTS' MATT VARNISH with Vernice Opaca "Artists" beneath it. Two short lines carry the whole specification: Removable. With UV Protection. The volume is printed 75 ml e beside the winsornewton.com address.

This is the brush-on half of a choice most painters only discover after buying the wrong one. A varnish in a bottle is applied with a soft flat brush in one direction across the picture, which gives control an aerosol cannot: you can see exactly where the coat is, work up to a hard edge, revarnish one panel of a diptych without touching the other, and use it in a room where a spray would coat the furniture. A bottle also wastes nothing to the air, where a good deal of any spray never lands on the painting.

What it cannot do is texture. Brushing across thick impasto or a raised palette-knife ridge drags the bristles over the high points, and on a picture with real relief a spray is the safer tool. Smooth to moderately worked oil paintings are exactly what this bottle suits.

Matt is chosen for glare. A varnished picture hung under a ceiling light reflects the bulb back at whoever stands in front of it unless the surface scatters that light, and a matt film is what does the scattering. The trade is small and real: the darkest passages sit a shade flatter than they would under gloss.

One thing worth seeing before you open it. The liquid reads pale cream through the glass rather than water-clear — our Daler-Rowney gloss varnish in the same 75 ml size is colourless in the bottle, and this one is not. Nothing on the label describes how the dried film looks, so brush a little onto the corner of a test board painted the same way and judge it dry before it goes near a finished picture.

Timing is the one rule that cannot be bent. Oil paint dries from the surface downwards and stays soft underneath for months, so the usual advice is to wait around six months before varnishing an ordinary oil painting and longer where the paint is thick. Use it in a ventilated room, keep it capped and out of reach of children, and let an adult handle it. Rs. 1,999 for the 75 ml bottle, with Cash on Delivery across Pakistan.

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