For artists who push the boundaries of traditional watercolor, work in sizes large enough that framing is not practical, or just dislike the barrier created by glass, varnish is a valuable option for protecting their paintings.1
Varnishing is likely to alter color, value, contrast, granulation, and the appearance of the paper in a watercolor painting. These modifications can be acceptable when balanced against the freedom varnishing offers.
In a previous article2 we investigated the changes that occurred when varnish was applied to washes of QoR Payne’s Gray, a paint chosen for its status as a chromatic neutral. The current test expanded our investigation to encompass washes of QoR Ultramarine Blue (PB29), Benzimidazolone Yellow (PY154), and Quinacridone Magenta (PR122) coated with GOLDEN MSA, Polymer, and Archival Varnishes. This combination allowed us to build a broader understanding of the aesthetic changes created when a watercolor is varnished. This article will discuss the varnish application that created the least aesthetic change to the watercolor over which it was applied, paying particular attention to the watercolor it changed the most.
The “Least Aesthetic Change” Challenge
We wished to see which varnish application came closest to the appearance of transparent watercolor on paper. Archival MSA Varnish Matte applied over Archival Varnish Gloss without an isolation coat won the “Least Aesthetic Change” accolade. We selected Ultramarine Blue as a visual example of this test (Image 1) since it presented the most change even when coated by the winning varnish. More information on the structure of our test may be found further into this article.
Depending upon the viewpoint and lighting, Matte Archival Varnish applied without an isolation coat marginally darkened and desaturated color. The matte sheen also slightly subdued the appearance of paper texture. Lighting and point of view influenced how easy it was to see these changes.
There also appeared to be variation in how people perceived the changes. Those of us with more background in watercolor found the differences to be obvious, while others thought the alterations so slight as to be negligible. Due to this difference in interpretation, plus the impact different colors, wash dilutions, and papers might have on the results, we would recommend that artists conduct their own tests before varnishing a watercolor painting.
Related Matte Varnish Results:
The runner-up to the combination causing the “Least Aesthetic Change” was structurally different through the use of an isolation coat between the two types of Archival Varnish. The isolation coat created a shinier surface than the Archival Varnish Gloss layers did by themselves. As a result, when Archival Varnish Matte was applied on top of this coating, it appeared less matte as well. Color also darkened a bit more than seen with the winning Archival Varnish Matte without an isolation coat. The varnished areas warmed color slightly, resulting in a more noticeable but still slight desaturation of color.
The other matte varnishes created more changes to the QoR Ultramarine Blue washes and watercolor paper (Image 2). Brush applied MSA Varnish Matte and Polymer Varnish Matte both desaturated color, and either lightened or darkened the paint or paper surface depending upon viewer position and lighting. The lightening is more obvious on darker color applications, and was seen with both of these brushed-on matte varnishes. Polymer Varnish appeared to darken the blue color slightly more than MSA Matte, while the MSA warmed the color more than Polymer Varnish Matte. The light blue wash shows these changes most clearly. Interestingly, these two matte varnishes appeared to emphasize granulation in the dark and medium washes of Ultramarine Blue, which is unique among all the varnishes tested.
Why would someone use an isolation coat?
An isolation coat creates a barrier between two layers of product. Since GOLDEN Varnishes are removable, having an isolation coat would allow a conservator working in the future to remove and replace the final layers of varnish without damaging the painting. Potentially, this replacement could return the artwork to its pristine just-varnished state, and rejuvenate a surface marred or dirtied by time. However, the more layers of product on top of a painting, the greater the aesthetic change will be. An artist should balance the potential for varnish replacement against the alterations an isolation coat might bring.
An isolation coat is especially important for brush application of MSA over an absorbent surface such as paper. Without a barrier, the solvent-based MSA sinks directly through the Archival MSA Varnish and into the paper. As our test shows, however, every additional layer over the painting’s surface increased the possibility of aesthetic change. Comparing the test results for Archival Varnishwith and without an isolation coat shows this clearly.
Varnishing created changes to color, value, paper texture, and sheen. In some cases, varnish modified color intensity and appeared to slightly warm the color of paint and paper. The appearance of change can be subjective, with varnished color appearing darker or lighter depending upon viewpoint and lighting. Viewing context also altered the perception of sheen and texture. We found that Archival Varnish Matte applied without an isolation coat created the least changes.
The Structure of the Tests:
We began with 300 lb. / 600 g.s.m. Fabriano Artistico Cold Pressed Extra White Watercolor Paper. Over this, we brushed horizontal dark, medium, and light washes of QoR Modern Watercolor Quinacridone Magenta, Benzimidazolone Yellow, and Ultramarine Blue. The test also included an area of unpainted paper. This created four horizontal bands across the paper (Diagram 1).
We applied varnish in vertical strips perpendicular to the horizontal washes. Uncoated “control” areas of paint and paper remained between each varnish test to allow for more accurate assessment of change. This created alternating vertical sections that were either varnished or left untouched to act as ‘controls’ for comparison. The process of creating the test specimens is described below:
First, to protect the water-sensitive and absorbent surface of paint and paper, four coats of aerosol Archival MSA Varnish Gloss were sprayed only where the varnish would be applied. Three or four coats are usually needed in this step, for the goal is to seal the surface and lock down the paint so no color will lift if a waterborne acrylic is brushed on the surface. Gloss preserves the greatest color clarity in the final result and is our recommendation for all early layers when varnishing.
Second, once the varnish was dry, an isolation coat of Soft Gel Gloss diluted 2 parts Gel to 1 part water was brush applied to three of the four varnish test areas. The goal with the isolation coat was to create an even, glossy surface and further seal the painting in case the final varnish needed to be removed in the future. An isolation coat was used to prepare for the MSA Varnish, Polymer Varnish, and one of the two Archival Varnish tests. The fourth varnish test area was preserved without an isolation coat.
Third, we applied the final varnish application. The MSA was diluted 3:1 varnish to MSA Solvent and the Polymer Varnish was diluted 4:1 varnish to distilled water. These two varnishes were brushed over dry isolation coats. The third test area with an isolation coat was sprayed with three layers of Archival MSA Varnish. The fourth test area, without an isolation coat, was also sprayed with three layers of Archival MSA Varnish. The two Archival Varnish applications would allow for a comparison between the Archival Varnish with and without the isolation coat.
Lighting for the Photographs
Two different lighting situations were used when photographing examples for this article. Light directed on the surface from the side created a more diffused illumination that allowed us to photograph color changes with less interference from varnish surface reflections. Moving the side light sources more to the front increased glare and emphasized sheen and its impact on the cold pressed paper texture.
Varnishing transparent watercolor permanently changes the painting while adding a protective surface that allows the artwork to be displayed without glass, much like an oil or acrylic painting might be.3 In this article, we discussed Archival Varnish Matte without an isolation coat since it came the closest to the original look of the watercolor on paper. We discussed the Matte Ultramarine Blue results because this color showed the most change even with the “winning” varnish. Please also keep in mind that the addition of acrylic varnish to a transparent watercolor might cause the artwork to be categorized as mixed media by some watercolor societies. To see images of all of the test panels, please go to the end of this article.
There is a component of subjectivity when applying varnish or evaluating the finished surface. Variances in application and materials may create different results, and viewpoint and lighting also change the way a varnished surface reads. We believe it would be best for an artist to create tests by varnishing sacrificial painted surfaces created with the paints, techniques, and papers used in the artist’s own watercolor paintings. These varnished examples would provide a more accurate example upon which to base a decision about whether to varnish a watercolor painting. The artist then would weigh the transformation against the liberating benefits offered by varnishing, to see if this is a direction he or she wishes to pursue when protecting a painting.
1 Cathy Jennings, GOLDEN Archival MSA Varnish Over Transparent Watercolor on Paper, Justpaint.org, October 4, 2017, Accessed October 3, 2017
2 Cathy Jennings, The Aesthetics of Varnishing Transparent Watercolor, Justpaint.org, May 15, 2017, Accessed October 3, 2017
3 Golden Artist Colors, Application Information Sheet: Varnishing Watercolors with GOLDEN Products, accessed October 4, 2017 and Golden Artist Colors, Resource Guide: Varnishing, accessed October 4, 2017