Glazing is a gem in the realm of painting techniques. Used throughout painting history,glazing is still popular today for styles from realism to abstraction and most mediums including oil, acrylic and watercolor. Here are my favorite tips on when and how to use it.

What is a glaze? The usual definition of a glaze is a transparent color, or application of a transparent layer of color onto a painting. A glaze is often applied to a painting in process, to shift whatever colors are already there. It can be applied very subtly to just slightly shift an underlying color, or more strongly to dramatically change underlying colors. In general though, it is usually used OVER a previously applied and dry, layer of one or more colors.

Why glaze? As an example, let’s say you are painting a portrait in a realistic style for a client. After months of hard work the portrait looks good enough to show to your client for approval. Your client, however, thinks the flesh tones are too yellow and wants you to fix it. What do you do? Argue with the client? Not a good idea. Return to your studio and repaint the entire face again? Also not a good idea. An easier solution is to apply a glaze over the flesh tones that will decrease the overall too yellow. By using purple, which is the opposite of yellow, in a VERY transparent layer this will be easily and quickly resolved.

How to make a glaze. Let’s continue using the above scenario. To reduce an overall too yellow color, we want to apply a very transparent purple glaze over it. To make the glaze mixture, start with any type of nonporous surface as a palette to mix your glaze color.

Some ideas for a palette:

  • a sheet of glass, palette pads (pads you can purchase made of gray or white sheets of coated paper)
  • disposable plastic plates (you can keep and reuse once the paint has dried)
  • sheets of freezer paper (not wax paper or parchment paper) taped to a table or piece of wood
  • shellac coated wood available in art stores as traditional painting palettes

On your palette of choice, squeeze out about a tablespoon of a clear medium (more or less depending on the size of the job at hand). Use a medium appropriate for the type of paint you are using. If working in oil use an oil medium, for encaustic (wax) use wax, and for acrylic use an acrylic medium. From here on, I will instruct as if for acrylic, where any gloss acrylic medium will be fine. These will appear white when wet, but dry clear.

Tip: Matte or satin acrylic mediums contain a white powder and may slightly shift your colors when dry.

Also add to your palette, not too close to the medium already there, a small amount of a purple paint color (I like to use Dioxazine Purple) in a 1:10 ratio. That’s 1 part paint to 10 parts medium. Mix it really well with a knife so it’s all homogenized. Mixing it with a knife instead of a brush will result in a well mixed color, making it easier to apply an even subtle layer of the purple glaze. To apply acrylic evenly without streaks, we need to slow down the drying time, to give us more time to brush it out smoothly before it dries. Oil painters don’t need to do this step because oil is already slow drying enough to easily apply an even glaze.

For our acrylic mixture, there are several options to slow down the drying of our glaze mixture. (1) add up to 15% retarder to the glaze mixture. (2) Instead of the retarder mentioned previously, substitute a medium by Golden called Acrylic Glazing Liquid. This medium already contains 15% retarder to 85% acrylic gloss medium. (3) Use a slow drying acrylic paint. I like to use Golden’s slow drying line of acrylics called OPEN.

Once you have made your mixture more slow drying, pick up a small amount using a smooth flat wash brush. Apply this mixture thinly to your surface to obtain an evenly applied transparent layer of color. If getting a smooth application with a brush is difficult for you, use a soft lint free rag instead of the brush.

Glazing an image to vignette

Here is another example where glazing comes in handy. For this painting I’d like to darken the top half sky area, just at the very top edge and close to the two side edges. This is called a vignette technique, closing in the image a bit to make the sky feel more contained and not as expansive.

Step 1. Since the glaze will go around the sides and top, I want the color to vary as I apply it, so the color won’t look too uniform – looking like a mistake or a wierd frame around the painting. So for this application I will not create just one uniform glaze color mixture. Instead I will use a variety of colors, adding them all into the mixture, but only combining it minimally so it isn’t all homogenized as in the previous example. I call this type of mixture a dirty mix glaze.

Pictured here, along with Golden’s Acrylic Glazing Medium in the center of the palette, I placed several earth tone colors: Sap Green, Burnt Sienna, Payne’s Gray, Raw Umber and Carbon Black. Dip a brush or rag (pictured here) into the medium first, picking up about ¼ teaspoon of the medium, then dip the same rag with the medium into a small amount of one or more of the paint colors. Both medium and paint will be on your rag or brush simultaneously but not mixed together. Now you can see why I call it a dirty mix glaze.

Step 2. Apply what’s on the rag onto the edges of the painting, using another clean rag to soften the edges wherever I stop glazing towards the center of the image. I use small circular motions instead of wiping lines parallel to the edges to avoid creating the illusion of a frame, and instead getting what I want – a subtle darkening at the edges.

Work in small areas while the paint is still wet. Switch to a clean brush or dry rag to remove some of the excess glaze to allow this newly applied glaze color to subtly blend into the image. As you finish one area, move along the edge using different combinations of color every 1″ – 2″ (25 – 51 mm). Avoid using the same color too frequently or applying the color too opaquely with not enough medium.

Here is the finished painting. Compare this to the original image. Notice the dark glazing around the edges to vignette, which creates a romantic mood and cozier feel in the sky.

Key Glazing Tips
The amount of medium you use makes a big difference. Use enough medium in your glaze mixture to make it transparent. It can be subtle to shift the underlying layer a small amount, or more opaque overlaying a more intense color coverage.

Always start with the medium on your palette, adding very small amounts of paint into it. If you do the reverse – starting with the paint, and adding medium into it – the mixture may remain stubbornly opaque causing you to go through large quantities of medium to get it transparent enough to your liking.

If your painting becomes too opaque in feel because you covered the underlying layers too heavily, you can sand of some of the upper paint layers once they are dry. Work by hand with pieces of waterproof sandpaper (I like grit 220) and lots of water. For large areas or heavy layers use an electric sander.

Additional Resources

Painting with Transparent Layers – A Glaze vs. A Wash

Glazes with Texture

Best Time to Use Glazes

Article from GOLDEN Glazing with Acrylics, Oils & Watercolors

Nancy Reyner is a professional fine art painter, international best-selling author and instructor. She offers assistance to artists in a variety of ways. Click here for more info.