MITRA Forum Question Details

​Hi -

You are correct that displaying watercolors without glass by varnishing or topcoating them in some way has gained a lot of popularity in the last few years, and while I cannot address many of the conservation issues, I would like to share the testing we have done on the degree of UV protection you get with UV filtering varnishes, vs museum grade UV Plexi, vs no UV protective coating. You can find that testing summarized here:

GOLDEN Archival MSA Varnish Over Transparent Watercolor on Paper

You will also find a really clear example of the amount of protection varnishing can provide if you scroll down to the image of Alizarin Crimson used 

Alizarin Crimson: Now You See It…..

That said, one can also not avoid the aesthetic impact that any coating of a watercolor will cause as understanding that is critical:

Aesthetics of Varnishing Transparent Watercolor

Summarizing some of the above, we would say that for substantial UV protection you would need to use a minimum of 6 sprayed coats of a UV Varnish but that will inevitably lead to a sense of the piece being laminated or at least clearly coated with a layer, that dramatically changes the aesthetic of the piece - invariably saturating and shifting the color and changing the sense of the surface and how light interacts with it. A far better option, if wanting to hold onto those aspects, would be mounting it behind non-reflective UV Museum Plexi. Expensive? yes - but really there is nothing else like it, and the best of them (such as the products put out by Tru View) can be nearly undetectable with no glare.

Addition issues to think of - once a varnish is applied directly to an absorbent delicate surface like a watercolor it is essentially unremovable and should be considered a permanent addition. The watercolor and the varnish or topcoat are inexorably linked and whatever happens to those topmost layers might not be reversible. Thus it becomes critical to chose something that will not yellow and one is still needing to handle, ship, store and mount these works with great care, treating them as delicate surfaces in their own right.

Not being a conservator I cannot speak to the issues of cleaning, or the difficulties of repair.

I would close by saying that of course artists will explore and push boundaries and there might be things that this approach offers that is not achievable in any other way - such as the ability to work larger or on things like canvas. But if interested in exploring this direction, do a lot of testing to really familiarize yourself with how these look aesthetically, and be willing to accept that in many ways your piece would no longer be a watercolor in the way that is normally understood. That is neither good or bad - just somethng to be accepted. It might very well open up new avenues of expression that are exciting to explore.

Hope that helps!

Hello!  Sarah's answer is great, and about as thorough as you can get, so I can only add a couple of things from a conservator's point of view.  From a paper conservator's perspective (or at least my perspective, others may of course have a different view), not enough testing has been done yet on how these newer varnishes age or degrade over the long-term to be able to predict how they might change a watercolor painting in the future, both aesthetically and physically.

I can say that varnishes can be exceptionally difficult to remove from paper, particularly as they age, and would also affect how cleaning is carried out.  My instinct is to suggest, as Sarah said, that you experiment to see if you like the results of using a varnish; but I tend to think that mounting under glazing is probably the safest way to protect and display watercolors on paper.

Watercolor owes its impact to the to the miraculous ability that water has to move pigment and other colorants, into fresh and lively patterns. Adding any surface coating, wax, varnish, or a synthetic dispersion, diminishes that impact, by adding a layer, through which one has to look to see the paint. These coatings are permanent and each has issues associated with it: wax may discolor, attract dust, and change the hue of the watercolor, varnish is likely to discolor and to change the hue of the watercolor, as will  synthetic dispersions. If the use of sheet glazing is too problematic, artists can paint in acrylic paint, encaustic, or other media on watercolor paper, but the paper can not be left exposed and the medium will have to stand up to traffic, oxidation, and other pollutants. Well sealed framing, with reflection canceling sheet glazing protects watercolor, and friable media from traffic, pollutants, including oxidants, and is well worth the investment.
Hugh Phibbs