Glazing keys


Dear Artist,

Glazing is a technique where a transparent, usually darker, tone is washed over previously painted and dried passages. While primarily an acrylic technique, glazing can also be used in oils and watercolours. A glaze is applied with a brush, rag, spray or flood. When I come up to bat, it’s often a rag because on-the-spot judgment may suggest both wipe-on and wipe-off.


Analagous orange glaze being applied over acidic yellow. Then those larches, as they say, will be ‘ready to go back into.’

While dismissed by many painters as trifling with the main thrust of a work, glazing nevertheless increases the range and variety of creative expression. Further, because tones are later adjustable, glazing permits casual and energetic early passages.

Here are a few glazing keys:

The darker the tone you put the glaze on top of, the lesser the effect.

Conversely, the lighter the tone you put the glaze on top of, the greater the effect.

Glazing with opposites on the colour wheel creates sophisticated and engaging neutral tones.

Glazing with analogous colours (next to each other on the colour wheel) can enrich areas of your work.

Masking first and then glazing over high-key or bright areas can be used to create effects of light and shade.

Overall glazing can pull weak paintings together and give them a more unified feel and “mother colour.”


Foreground elements being toned down with a black glaze. Depending on the black you use, it can be either warm or cool.

Thin glazes of black effectively tones down garishness and sets up for “colour surprise” and “coming to light.”

Experimenting with thin glazes of Phthalo blue shows the potential before branching out to other glazing pigments.

In acrylic work, glazes automatically add a small amount of medium, thus improving the long-term health of surfaces.

With progressive layers of glazing, you can creep up on and find the tone you want. For those who seek correct and realistic balance between tones, a series of thin glazes will often do the trick. Overly dark passages can be subjected to glazes as well. Glazing with a lighter tone, in other words, with the addition of a somewhat transparent white, Naples yellow, yellow ochre or other pigment, can be a bit of a sticky wicket. You need to think of glazing in a sporting manner — it’s just another pitch and while it’s not everybody’s cup of tea, it’s still Cricket.


“Larches from Opabin Prospect, Yoho Park, B.C.
acrylic on canvas 30 x 34 inches
Glazing isn’t everything, but it helps.

Best regards,


PS: “Trifles make perfection, and perfection is no trifle.” (Michelangelo)

Esoterica: I like to pre-mix a variety of glazes and keep them in squeeze bottles. These days, my thin glazes consist of about 5% pigment, 45% acrylic medium (gloss or matte) and fifty percent water. Glazing affects different surfaces in odd ways, especially where molding paste or impasto has been used. As usual, happenstance effects are gifts to be treasured.

(RG note) Readers may have noticed I’ve been travelling in Eastern Europe. Through the marvels of satellite technology, the twice-weekly letters still found their way to your inbox. Now that I’m back in the studio, we’ve added some illustrations to go with the last few clickbacks. You might consider scrolling back there to see illustrated highlights relating to the letters. Going back through them myself, I’m amazed at the quality and variety of reader input, as well as the remarkable live comments. For those who write us, thank you so much for making these valuable contributions to the brotherhood and sisterhood of artists.


Working both ways
by Dyan Law, Pipersville, PA, USA


“Visiting The Spring House”
oil painting, 32 x 36 inches
by Dyan Law

I’ve used glazing techniques in my paintings long before I heard the term “glaze.” It seemed to be a logical process when attempting to create a glow or change the overall harmony of an object, person, place, etc., no matter what painting medium I was using. However, a problem occurred when I tried to paint simply and directly. I began to have difficulty applying pure, clean colors. I had become too accustomed working in multiple layers, aiming to achieve an effective, vibrant end result. It was back to basics for me!

I learned that with practice I could work directly and indirectly, glazing later stages of my work, with only a few exceptions. I prefer not to restrict myself or my students by choosing one method of applying color over another. Instead, I enjoy and encourage putting colors “to the test” to see what each color will “do” on its own as well as in layers. Often the results are magical!

(RG note) Thanks, Dyan. Yep, for sure, that’s a downside. The constant recourse to glazing can dull your capability at accurate early-on colour picking.


Crude application?
by John Fowles, Ditchburn, UK


The first American stamp to use the Giori Press was the 1962 Project Mercury issue. Notice how the light glow on the underside of the craft bleeds into the sky. This effect tended to vary from stamp to stamp.

With such a crude applicator as a balled-up rag, how can you accurately cover small areas that need to be glazed?

(RG note) Thanks, John. Several artists asked this. Actually, small areas can be attacked by pointing the rag. In practice, a little overshoot is not bad. It creates what I call the “Giori Press Effect.” The Giori was a printing press that permitted engraved work to go through the press in only one pass rather than one pass for each colour. The machine was invented by Gualtiero Giori about 1950 and was used on a worldwide basis for printing engraved postage stamps. The inking was done by rubber rollers that were cut in specific zones, but there tended to be some “bloom” or “glow” where the ink bled or overlapped, which turned out to be not such an unpleasant effect.


Oil glazing tips and warnings
by Gary Godbee, Clark, NJ, USA


“Perce Rocks”
oil painting, 10 x 10 inches
by Gary Godbee

Although not in as much use in the past century because of the (relatively) recent dominance of direct oil painting techniques, glazing and scumbling are two primary aspects of the indirect painting technique employed by the vast majority of oil painters from the fifteenth century until the mid-nineteenth century and advent of Impressionism. I know that the glazing technique is more prevalent today among acrylic painters than oil painters, but I thought it was worth pointing out that it has a very long and distinguished history based in oil painting that certainly predates the development of acrylic paints. As an oil painter, I know of many other contemporary oil painters who use a combination of direct and indirect painting in their work, and I have been teaching my oil painting classes the basics of glazing for years. (The addition of a small amount of linseed oil to the color is essential, but one must be careful not to disperse the pigment so thinly that it separates from the oil binder)

The rest of your letter makes a wonderfully strong case for incorporating glazed passages in one’s paintings to achieve certain unique effects, although it might be pointed out that glazed passages in oil (although I suspect not in acrylic) are susceptible to being accidentally removed during conservation and cleaning (and removing old varnish) if the glazed passages are the last of the painting. It’s generally a good idea to paint into glazed passages with semi-opaque and opaque paint after the color change or unifying effect has been achieved in order to increase its permanence. As a counterpoint to that, however, there are some wonderful passages of pure glazed color in a number of Rembrandt’s paintings that are fully intact even after centuries and multiple cleanings.


Rembrandt’s formula?
by Diana Dean


“The Four Knights”
oil painting, 81.5 x 54.5 inches
by Diana Dean

I have been glazing in oils for many years. I start with 2oz damar, 2oz stand oil and 10oz turpentine. I use it in the traditional manner of first putting on the glaze and then working in to it. When this dries I add another glaze adding another oz of stand oil (fat over thin) to the medium with every layer and reworking the painting. My paintings usually have at least 8 layers where I am altering the colour as well as moving the subject according to the developing structure. The glazes build up gradually to give that traditional sheen and depth in the work. I read somewhere that this was the medium that Rembrandt used, although this is still a question. The quantities in the medium for the developing painting have been from my own format. Very occasionally I have seen cracking occur, maybe because the paint layers have got too thick and I didn’t add enough oil.


Trying new things
by Jack Dickerson, Brewster, MA, USA


“Catboat #10, Sunset Fog”
acrylic on canvas, 46 x 65 inches
by Jack Dickerson

I’ve experimented with glazing for some time now, and tend to do the opposite of what you stated in your first paragraph. I tend to use medium to light colors, either not mixed or barely mixed to accomplish a lot of different things: 1) to intensify underlying small sections of color, 2) to subdue backgrounds and give them small hints of color overlay, and 3) to build up many layers of different colors to give the work a sense of depth and luminosity. I use the last of these techniques a lot to slowly build perspective and reflections and shadows. The effect can be pretty amazing when I use ONLY glazes to build an entire painting. Here is an example of a painting that was developed slowly with 90% glazes, small amounts of diluted color, and tiny amounts of straight undiluted color. I am an experimenter. I can’t resist trying new things.


Sunny glazes
by Petrina Gregson

I wanted to give a sunnier aspect to an area of my painting; but it seems my Cadmium yellows are opaque. I didn’t want the pink or red of Alizarin Red. Can you tell me how I can achieve a yellow glaze with oils? (I have Walnut oil, Walnut Alkyd, and Liquin at my disposal.)

(RG note) Thanks, Petrina. Yellow glazes are the most difficult, not only because they are often opaque, but they are at or near the top of the colour wheel. There used to be a very good oil glazing yellow called, surprisingly, “Dutch Pink” reportedly used by Rembrandt, but it has been displaced in many colour lines with more modern (and less fugitive) quinacridones and others. Dutch pink squeezed out as a weak pink but spread to a remarkably transparent golden yellow, quite a delight to work with. Another way you can warm up paintings is with an application of what is essentially a “varnish stain” such as you might put on the deck of your boat, only carefully-crafted with Copal oil medium, Liquin, Damar, or other suitable varnish medium. By mixing judiciously with transparent warms, you can achieve maple, mahogany and other warm and woodsy looks.


Oil glazing made simple
by Jennifer Mason, Toronto, ON, Canada


“Lyengar detail”
oil painting
by Jennifer Mason

A simple method of glazing in oils is to just paint a thin transparent layer of one colour on top of another. The colours mix optically, like looking through layers of stained glass, and this can create a luminosity that simply cannot be achieved any other way. There are even oil painters who make highly finished grisaille paintings and then add all the colour through glazing, although the time required to this would drive most of us crazy, me included. As you demonstrate, glazing can also be used as a corrective measure, to change a colour slightly, or to unify a painting with a wash over everything. Because the under layer must be dry enough that it won’t mix with the glaze on top, this takes time in oils, and we must also observe the fat over lean principle or the work will crack/wrinkle, so a simple process can get more complicated. Glazing is one of the main reasons I’m an oil painter, but I’d love to know about anyone who can create these subtle effects with acrylics. I’m currently experimenting with a tiny bit of interference colour in oil glazes. We have so many wonderful materials available to us.


It’s all ‘trifling’
by Nikki Coulombe, Lewisville, TX, USA


“Sun Shower #4 left detail” acrylics, masking medium and glazing exploration, wrapped canvas
by Nikki Coulombe

I don’t understand what other painters mean by saying that glazing trifles with the main thrust of the work. I’m puzzled how one might find ways to achieve successful work without “trifling”? Thankfully you added Michelangelo‘s comment at the end of this clickback, which supports working through various processes and trying to discover new ways of creating the thrust of the work. If artists refuse to explore and experiment they will not progress much in their knowledge or skills. Discovery contributes to future works. Yes, everyone please give glazing a try.

(RG note) Thanks, Nikki. I was referring to those purist outdoor painters that like to have a painting happening “alla prima.” Plein air does not always lend itself to glazing techniques, particularly if you are working in oils. The purist mentality, to its credit, teaches the painter to get it more or less right on every stroke. Nice going if you can pull it off.


A pilgrim’s progress
by Tim Adams, Eureka Springs, AR, USA

I have recently started using glazes more, and it has really changed the whole nature of the paintings, lending them a more finished, professional look. Thank you for your continued help over the years. I stumbled across this site about 8 years ago, and even though I rarely respond, I almost never miss a letter. I began painting in 1998, and have been on the self taught art train ever since. At first I was happy just to be “making original art,” but then over the years went through all of the periods described in an old letter of yours: Unskilled Art “Wild, primitive, abstract, visionary” …everything but skilled. After 10 years of progression and thanks to your constant input on the subject of quality, I am making some headway in honing my craft and developing some degree of quality.


‘Glazing’ a film with music
by Chris Boghosian, Los Angeles, CA, USA

As a filmmaker reading your letters, I am constantly drawing parallels between painting and the craft of filmmaking. Whether you write about brush strokes or gallery politics, the similarities are frequently there. Such is the case with your most recent letter, “Glazing Keys.”

Most films, whether short or feature length, are given a score, i.e., music, once the editing is finalized. In many ways, it is the glazing process of moviemaking. You wrote, “While dismissed by many painters as trifling with the main thrust of a work, glazing nevertheless increases the range and variety of creative expression.” So true with films as well. Many purists, including myriad Filmmaking 101 teachers, argue that music overrides the visuals and is a shortcut to evocation. On the other hand, can you imagine LAWRENCE OF ARABIA without Maurice Jarre’s original composition, or PSYCHO without its iconic screeches? Whether it is a single, repeated note or an extravagant composition, music can turn a film into a masterpiece.


Fat over lean
by Betty Billups, Sandpoint, ID, USA


oil painting
by Betty Billups

For oil painters, when glazing, or for any “on top of old paint” painting… use caution with certain colors. Using a “lean” color over a “fat” color will cause problems in the near future of a painting’s stability! If you use a lean oil color over a fat oil color, you will create a very unstable surface… the chances of that area eventually cracking is probable, and possibly falling off!





Curious about ‘Cuckoo artists’
by Milos Vujasinovic, Belgrade, Serbia


“Ballad of a City on the River”
oil painting
by Milos Vujasinovic

In my lifetime of painting and collecting art, I have come across some cuckoo artists who will deny their work is theirs. I have experienced this phenomenon here in Serbia, on part of the artists whose work I occasionally find here and there. I put a great deal of effort into figuring who they are and then going through even more trouble of reaching out to them. On one occasion, it was a known artist who used his wife as a sitter. But she, an alcoholic, forbade to him to admit it was his work. I coined term the cuckoo artists, since these sorts of paintings appear in different collections like cuckoo eggs. Examples are the US artist Stan Twardowicz and the Spanish 20th Century master Agustin Ubeda.

There are 2 comments for Curious about ‘Cuckoo artists’ by Milos Vujasinovic

From: Anonymous — Nov 14, 2008

Just one correction. Stanley Twardowicz and Agustin Ubeda are counterexamples, I never had problems with them. – mv

From: Anonymous — Nov 14, 2008

Phenomenon is even more intriguing since majority of these cuckoo artists are rather unknown except in the said case, whereby the painter had recognized the model, a guy named Ace who used to pose at the University of Fine Arts in Belgrade.


Contentious letters
by B.J. Adams, Washington, DC, USA

I so enjoyed and was encouraged by the information in your last letter, Eyes over the border that I sent it to several non-artist folk. Then today, I was appalled to read so many negative responses in the clickbacks. If the percentages of negative comments were as high as they appeared, today, Barack Obama would not have been elected President. Everyone I talk to is elated and looking forward to the next few years with much anticipation. Please don’t stop making any comments about anything in the world that comes to your mind. I guess you can’t please everyone all the time but most of us are open to read anything and your writing has always inspired.

(RG note) Thanks, B. J. If it’s any consolation there were more unsubscribes when I mentioned last summer that I drove a Quad ATV some seventy miles for one day in the northern Ontario woods. It was the only time I’ve tried one of those noisy little machines as a mobile easel and I think I may have scared a moose. Actually, the positive responses to Obama’s election in this inbox vastly overwhelmed the negative ones. At the same time, many, many artists and writers from other countries seem to be taking a quiet “wait-and-see” position.

There is 1 comment for Contentious letters by B.J. Adams

From: ARTucker — Nov 13, 2008

Many of us held back making comments. What’s done is done and that must be acceptable, although not necessarily of our liking.



Archived Comments

Enjoy the past comments below for Glazing keys



From: Cheryl Webster — Nov 10, 2008

Thanks for your tips on Glazing. Only this am I came across a slowly hardening of acrylic matte glaze and wondered when I would find out what exactly to do with it. I shall definitely do some experimenting with it.

From: Hallvardur Asgeirsson — Nov 10, 2008

you rock, dude!

From: Asma Abbasi — Nov 10, 2008

I love your painting Robert. I often struggle with my composition and tones while it seems so natural with your work.

From: Faith Puleston — Nov 11, 2008
From: Laurie — Nov 11, 2008

I use glazing often in my work. I like how well it works with acrylics. I have often used yellow ochre as an underpainting in my skies and then a prussian blue over, in thin layers.

From: M Smith — Nov 11, 2008

I use glazing techniques in oil and watercolor. Glazes can punch up a work or tone it down and fix some paintings that were not going to make it out of the studio. I was taught that adding white to a glaze made it a “scumble”.

From: Hank — Nov 11, 2008

Thanks sooo much for all your insight. Where does one look for more info on glazeing???

From: Helen Musser — Nov 11, 2008

Robert, Thank you so much for this letter. You’ve given us knowledge that can take years to acquire. You are a master.

From: Carol Nelson — Nov 11, 2008

I’ve often used glazing on acrylic paintings for the unifying effect you mentioned. For oil paintings, I use Liquin plus pigment for the glazing medium.

From: Marge Healy — Nov 11, 2008

Thanks so much for the information, I have to get the courage up to try it.

From: Rick Rotante — Nov 12, 2008

Robert- Clarification — Glazing is not primarily for acrylics. In fact, acrylics were not even invented when the masters (i.e. Vermeer, Michelangelo, Velasquez et al) were doing glazing. This technique is much older and was done through the Renaissance and later. Glazing fell out of favor when alla prima techniques became the rage.

And I’m not sure you can use this method with watercolors. But here I can’t be sure. We need some watercolor artists to chime in on this.

From: Russ Hogger — Nov 12, 2008

When I started using acrylics over 30 years ago, I thought it was the best thing since sliced bread. I’ve heard all the complaints from my oil painting friends and the most common one, it dries too fast. For me acrylic is a very forgiving medium. The faster it dries the better I like it. I work very loose. Making alterations are easy to do. In regards to glazing techniques, when I’m throwing paint around on the canvas I sometimes mix a little too much water in the paint which can turn into some happy accidents. As in watercolors the more water in the mix the more the color underneath shows through.I should mention that I only use bristle brushes. I go for the brushy effect. The other big complaint with acrylics is that it darkens slightly as it dries. With experience you learn how to compensate for this.

From: John Ferrie — Nov 13, 2008

I often have artists contact me and ask either my advice or if I know about this technique or that. Recently I received an email from a friend in Colorado asking if I have ever heard of Verre Eglomise. I knew of it as I had seen another artist friend do it as well as a seminar from art school back at the turn of the previous century. Verre Eglomise is a term used to describe the art of cold painting and gilding on the back of glass. What I always suspect when people delve into these techniques is their art becomes more of a craft. While I admire Potters for what they do and all they need to know, it rarely breaks through the glass ceiling of being a craft. There is nothing better than admiring an artists work who is just a good painter. I love when I come right up close to a canvas and image the thousands of hours an artist spends with their work and the acres of canvas they have created. Making brush strokes sing with paint application is study enough for this artist. When artists start weather vaining about what to paint or how to do something, their inner voice rarely comes through… Then again, that’s just me.

From: Margo Buccini — Nov 14, 2008

Like ‘Bill Brown’, there was another ‘interested buyer’ from the Ukraine. She went as far as sending bogus check for $2000. Luckily, the bank checked. Somehow, she had gotten information & bank numbers from a legitimate artist on Painter’s Keys. We contacted this artist immediately, and she closed her account. Please be very careful in letting out any personal information! Be wise. Check the credentials of any ‘buyer’ before sending anything! Good luck.

From: Marie Louise Tesch — Nov 14, 2008

Apparently I’ve been a subscriber long enough to see the repeating patterns. Had to smile as I read about others discovering and re-discovering glazing. Must be time to pull up the examples of Maxfield Parrish again. Fortunately, there were some unfinished works so one can see his process. For your readers: just use the search key at the top of this site and type “Maxfield Parrish” – you will find Bob’s earlier letters. What a great website – so easy to move around.

From: Glenn Perry — Nov 14, 2008

Painting conservationists don’t condone the use of damar or other natural resin varnishes as part of any oil painting medium. The issue is where does the varnish layer stop and the paint layer begin when removing the discolored varnish. There will also be yellowing and darkening within the paint layer itself which is not reversible by cleaning. And this happens a lot sooner than you’d expect. Another issue is that these resins do not dry to a non resoluble film for some time, so how ‘dry’ is that paint when it’s covered with the next application. The medium of ‘thirds’ was the standard taught when I attended the Pennsylvania Academy of the Fine Arts in the ’70’s. and I have used it until recently. Now I use stand oil and Gamsol in various proportions, if damar was used turpentine would need to be the solvent.

From: Miguel Westerberg — Nov 14, 2008
From: Carolyn Edlund — Nov 15, 2008

One of the respondents to your letter on glazing expressed frustration with opacity when attempting to beef up yellow tones in their paintings. Indian Yellow is less opaque than others, has a high tinting strength, and brilliant hue; it may well serve this artist’s purpose. (I use Winsor & Newton.) An additional note: if glazing lighter over darker tones, carefully observe the end result to evaluate whether direct painting or scumbling might achieve a preferable result. Using lighter tones risks a chalky-looking surface.

From: Beverly Shuford — Nov 20, 2008

I need to know glazing techniques in watercolors and what colors work best in WC glazing. Thanks





Estuary Fall Colours

acrylic painting
by Brian Buckrell, Comox, BC, Canada


You may be interested to know that artists from every state in the USA, every province in Canada, and at least 115 countries worldwide have visited these pages since January 1, 2013.

That includes Mark D. Gottsegen of Climax, NC, USA who wrote, “Your phrase, ‘While primarily an acrylic technique…’ ignores more than 500 years of art history.”

And also Ken Campbell of Victoria, BC, Canada who wrote, “To a hammer every problem is a nail. This is such a fun turn of words and so instructive. We tend to respond to the world from our own perspective. And why not?”

And also Elisabeth Nitteberg in the south of France who wrote, “I very often find myself using my fingers to apply thin mixes of oil onto the nearly dried paint.”

(RG note) Thanks, Elizabeth. Hard to resist — using the old fingers for a smudge and smear here and there. If you’re making a habit of it you better start using rubber gloves.




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