
Finally! Here’s the masking film lesson I promised in a blog post way back in February. Thank you patient blog followers and a special thanks to reader “Gabrielle” for her kind and gentle reminder to me to make good on my promise!
PROCESS OVERVIEW
Traditional transparent watercolor painters do not use white paint. Instead, the white of the paper is preserved throughout the entire painting process. The safest, best way to save white paper areas larger than one half inch in diameter is to use masking film. Most of the time (especially if I plan to paint a really juicy-wet background wash) I mask foreground subjects with clear Con-Tact paper sealed with masking fluid (liquid frisket) and paint the background first. When the background is finished, I remove the dried masking fluid and Con-Tact paper, then re-apply masking fluid to the subject’s pure white and nearly white highlights.

Masking saves white areas with very crisp, sharp, hard edges that can be softened later in the painting process.
MATERIALS
--CLEAR Con-Tact or other light adhesive backed shelf paper
--Black Sharpie fine point permanent marker
--Winsor and Newton Colourless Art Masking Fluid (the BEST!)
--Masking fluid application tools (see blog post February 16, 2009,
Top 10 Watercolor Masking Tools and Supplies)
--Rubber cement pickup
--Scissors
Important tip! Don’t buy expensive artist’s masking film or frisket film for watercolor painting. It’s a wonderful product for air brush, acrylic, pastel work, and any application where you need crisp, clean painted edges because the edges seal so nicely on smooth surfaces. Masking film is not intended for use with wet, soupy washes on textured paper like Arches 140 lb or 300 lb cold-pressed watercolor paper. Instead, use Con-Tact brand paper or other shelf paper with light adhesive backing. You will save a lot of money and produce the same result. No adhesive residue remains on the watercolor paper.
INSTRUCTIONS
Tape the Con-Tact paper over your painting and trace a line on the RIGHT side of the Con-Tact paper with a Sharpie marker, 1/16” to 1/8” inside the pencil line of the shape to be masked. Warning: Be really careful about using the Sharpie marker near your watercolor paper. It’s permanent!
If you can't see pencil lines on the watercolor paper through the Con-Tact paper and backing, here are three suggested work-arounds:
1) Trace the shape 1/8” inside the pencil line onto tracing paper, cut out and lay the tracing paper over the Con-Tact paper. Draw a line around the shape with a Sharpie marker.
OR 2) If you transferred your line work to the watercolor paper from a full sized line drawing, tape the line drawing to a window or light box, lay the Con-Tact paper over the line drawing and trace your line onto the Con-Tact paper using the Sharpie marker. Remember to trace 1/16” to 1/8” inside the original pencil line.
OR 3) Place clear acetate film over the pencil sketch on your watercolor paper. Trace a Sharpie line on the acetate 1/16” to 1/8” inside the edge of the shape to be masked. Place the acetate on a light box or window. Tape Con-Tact paper over the acetate and trace the line onto Con-Tact paper with the Sharpie.
Using scissors, cut out the Con-Tact paper shape along the center of the Sharpie line, leaving a solid black line all the way around the shape. If you need to, draw along the edge of the Con-Tact paper with the marker to make a continuous solid black line. This line is VERY important because it is your guide for applying enough masking fluid. Do not over-cut inside corners. This is the most common reason for getting a watercolor “bleed” or leak under the Con-Tact paper. If you do cut too far into a corner, just mark the edges of the cut with the marker and remember to cover the entire cut and slightly beyond with masking fluid.

Remove the backing from the Con-Tact paper and position it on your painting. Apply masking fluid all the way around the shape, sealing the Con-Tact paper to the watercolor paper by bringing the fluid right to the pencil line of your shape as well as over the Con-Tact paper a minimum of 1/16” inside the Sharpie line. When the masking fluid dries, the black Sharpie line will show through indicating places where you need to apply extra fluid to prevent bleeds. Strangely enough, most bleeds originate from the Con-Tact paper side of the masking fluid, not from the side closest to the pencil line.
After the liquid frisket is totally dry, you can apply watercolor washes. You WILL get a bleed….if not today, then someday! It happens to everyone. Here’s one of mine on the fisherman's hand.

Just understand that it’s not the end of your painting. We can always lift and scrub, right? Watercolor painting keeps me very humble. My philosophy is to accept “what is” and keep on keeping on! It’s all good!
Removing the masking film is easy. MEGA-IMPORTANT TIP: Your painting must be totally bone dry before you remove masking or you risk tearing the watercolor paper. Using a rubber cement pickup, lift one piece of the dry masking fluid until you can get a good grip. Slowly and carefully peel that fun-stretchy-rubber-bandy-stringy-latex hand-over-hand from around all the edges, then gently lift and peel back the Con-Tact paper. Remove any masking fluid residue from your painting with the rubber cement pickup. Now you are ready to apply masking fluid to highlights that were under the film and finish your painting.
I'm delighted to share my techniques and information with fellow artists and hope you find this information helpful and useful. Comments or questions are always welcome! c.2009 Connie Williams
Jack in the Stalk 14 x 22 Watercolor - My husband, Jack, fishing near Stalk Creek in Spatsizi Plateau Wilderness Provincial Park, British Columbia.