Performers in later times, such as the impressionist era, often used this Wet-on-wet technique more commonly, mixing the wet colour on the fabric without following the Renaissance-era strategy of including and replacement windows. Abstract Oil Paintings This technique is also known as "alla prima". This technique was designed due to the introduction of artwork outside, instead of within a facilities. While outside, an specialist did not have enough time to let each part of colour dry before including a new part. Several modern artists use a mix of both methods, which can add strong shade as well as the detail of levels through replacement windows. Da Vinci Paintings When the picture is completed and has dry for up to a season, an specialist often closes the perform with a part of varnish that is generally created from damar gum deposits demolished in turpentine. Such varnishes can be eliminated without distressing the oil artwork itself, to allow washing and efficiency. Some modern artists choose not to varnish their perform, choosing that the areas stay varnish-free.