Sign In
  • UD Search
Toggle Navigation

Open the Navigation Management window, which can be used to view the full current branch of the menu tree, and edit it.

CONNECT
  • Facebook

MITRA Forum Question Details

Image Picker for Section 0

 ForumQuestion

  • Creating Glazes with Egg TemperaApproveRejectUn-ApproveSubscribeUn-Unsubscribe
    Question asked 2016-12-16 15:56:21 ... Most recent comment 2016-12-16 16:13:00
    Art Conservation Topics Egg Tempera Mural Painting Solvents and Thinners
    Question
    I'm trying to develop some glazing techniques to use on egg tempera paintings. I need to slow the drying time down. How should I go about this ?
Answers and Comments
  • EditDeleteModerator AnswerI am assuming that you are referencing pure egg yolk tempera paints and not egg-oil tempera emulsions. I am also going to assume that we both mean the same thing when we write glaze; a darker and transparent, or translucent, color applied over a lighter color to create an indirect painting effect. In my experience, difficulties in glazing egg tempera paints are often the result of attempting to glaze broad areas too early in the painting process. A proper ground for pure egg tempera paint is very, very absorbent, so much so that attempts to make broad washes or glazes are extremely difficult without resorting to specialized techniques like the petit lac method or the use of non-traditional application tools like sponges, etc. As the painting progresses and solid layers of tempera paint are built up, the paint stratigraphy becomes less absorbent and glazing becomes easier and easier. Egg-oil emulsions can slow down the setting rate of paints made with them. Small additions of oil do not greatly change the handling properties in the manner you hope for while very large additions really transform the painting medium into something very different. Personally, I do not feel that the benefit is drastic enough to warrant difficulties that it does add. The small additional working time is offset by a real hampering of the quick application and reworking the surface so easy in straight egg tempera. As far as other additions used to slow down the setting/drying rate of egg tempera paint, I would not recommend them. It is generally not advisable to interrupt the natural drying/denaturing of a paint binder in such a manner. Others may have a very different opinion and experience. I will forwarded this tread to some other egg tempera painters who are real experts with the medium for their opinion on your question. They may have very different opinions on the subject.
    Baade, Brian
    2016-12-16 16:51:37
  • ApproveRejectUn-ApproveUser CommentEgg tempera does not lend itself to "glazing" in the sense of that word as applied to other painting mediums, such as oil paint. Since egg tempera is applied very thinly it is transparent without the need to add medium to lower the pigment volume in the paint film. In fact, egg tempera typically has a very high pigment volume compared to all other solids in the paint film, and attempts to lower this volume significantly results in problems for the paint film due to overbinding the pigment. There are ways to slow the drying time, but as Brian Baade has already commented attempting to interfere with the natural drying rate of egg tempera creates many other problems. George O'Hanlon
    2016-12-16 17:54:44
  • EditDeleteModerator AnswerHi...we are also wondering why you tagged your question under "Art Conservation Topics" and "Mural Painting"? Are you attempting to restore an egg tempera mural painting?
    Kristin deGhetaldi (CAS)
    2016-12-16 20:46:46
  • ApproveRejectUn-ApproveUser CommentI don’t know precisely what you mean by “glazing” (people have different definitions) or the reason you wish to slowing drying, but here are some thoughts. I define a glaze as a layer of transparent color – like a sheet of tinted cellophane - placed over parts or all of a painting. I agree with Brian that is it generally dark color over a light (most colors are mid to dark values), but I also think that a veil of transparent yellow over blue behaves like, and thus can be considered, a glaze. I also agree with George that, whereas in other paints (such as oil) adding medium is the means by which you lay down a transparent layer of color, you neither need to, nor should, add more medium (yolk) to tempera to make the paint suitable for glazing – adding extra yolk merely throws off the “tempering” (ratio of yolk to pigment) and makes for a gummy paint that’s apt to crack. Once you’ve achieved the correct ratio of yolk to pigment (about equal parts each) only water should be added to change the consistency of the paint. And since water evaporates you can add as much as you like, to create whatever paint consistency for glazing you desire. As Brian mentions, you could slow drying by adding oil to the yolk to make an egg oil emulsion, but I agree that in order to significantly impact the working properties of the paint you’d have to add enough oil that you wouldn’t be working with egg tempera anymore, but with a new medium, tempera grassa – so it’s not a solution that keeps you in the world of egg tempera. I am guessing that the reason you want to slow drying is to give time to manipulate the paint, so you can lay down a consistent, smooth glaze – is this accurate? As anyone who works in tempera knows, it’s a “mark medium” – it’s not possible to physically blend paint once it’s applied because reworking paint dissolves and lifts underlying layers. Thus whatever tool is used leaves behind its mark: A brushstroke stays visibly a brushstroke, sponged on paint carries the imprint of a sponge. As the layers build the surface becomes a bit resilient, you have a little more time to noodle, but not much, and lifting of underlying layers still occurs if you mess around too long. Lifting stops only when the underlying paint has cured, which can take anywhere from a few weeks to months. Most painters can’t wait that long to add the next layer (especially given that one of tempera’s charms is quickly building innumerable layers). Tempera’s “mark making” tendency means it is ideal for rendering fine details, crisp textural effects, and other linear elements. The challenge is to create smooth, mark-free transitions or, in the case of glazing, an even application of transparent color. You cannot get rid of the “mark” in tempera, but you can control and minimize it. If this is what you are struggling with, here are some options. 1. USE VERY THINNED PAINT Once paint is properly tempered (has the correct ratio of pigment to yolk) it can be thinned considerably with water. This watery paint can be applied two ways: First, as a “petit lac”, as Brian mentioned. You essentially put a puddle of paint on the surface (work horizontally) and, without breaking the surface tension, spread out the paint with the tip of a brush. This can result in a mottled effect, but also, with a lot of practice, you can manage the paint so it results in a relatively smooth application of color. The second way to work with watered-down paint is to load a brush and then – this is critical - wipe the brush (I press the tip between fingers and a rag). You want enough paint left in the brush to lay down a smooth-flowing mark, but not so much paint that it creates puddles. It’s akin to working dry brush yet strokes don’t “chatter” or skip; the paint flows in a smooth, controlled manner, and dries quickly. When a very much-thinned paint is applied this way it creates a faint, less distinct brushstroke: no big color or value changes from the underlying color, and less sharply defined edges. If enough visually inconsequential marks, with very faint, indistinct contours, are painted one atop the other, eventually they add up to a layer of glazed color with a minimum of marks. However, very faint brushstrokes are so inconsequential that A LOT of them must be applied to add up to something. Two things can be hard for people to grasp: (1) The degree to which paint must be thinned with water so that it doesn’t leave behind too much of a mark (people generally don’t thin their paint enough and make too distinct, sharp-edged of a brushstroke); and (2) How many layers of very faint paint must be applied to add up to something (people tend to stop before they’ve put on enough layers). It is this simple: If you apply paint and it creates too much of a mark, then you are leaving too much of a mark. Don’t judge if the paint is sufficiently thinned by how much water you’ve added or how it looks on the palette; believe the evidence of the brushstrokes on the panel. If the paint creates a delineated mark – a distinct line that interrupts a smooth application of color - the paint has not been thinned enough. Add more water to the paint and try again. I build many layers of this very, very watered-down paint applied with a well-wiped brush. Very gradually the layers add up, woven from scores of faint brushstrokes. Watching a painting emerge this way is like seeing film incrementally develop; or looking into a room as a dimmer switch slowly turns and gradually reveals objects within. 2. USE BROADER, MORE AMORPHOUS PAINTING TOOLS The broader the tool, the less individual, fussy marks you create. I know many tempera painters who apply glazes with 1 to 2” wide, flat watercolor brushes (using thinned paint, as described above). I use flats too, but my preference is a sponge – either kitchen sponge cut into a 2” square, or cosmetic sponge (which has a smooth surface). There are other considerations to these methods, but already I’ve gone on too long. My experience as a tempera teacher is that people often give up before they’ve achieved smooth glazing in tempera because they think it’s impossible. It’s not. But it does take a lot of attentive practice. I hope that helps. Koo Schadler
    2016-12-19 13:12:42
  • EditDeleteModerator AnswerKoo, great response. It is wonderful to have a tempera master weigh in on this question.
    Baade, Brian
    2016-12-19 13:21:01
Page Settings and MetaData:
(Not Shown on the Page)
Page Settings
question
No
MetaData for Search Engine Optimization
MITRA Forum Question Details
restricted
This page cannot be accessed until you accept the Terms of Use, which can be found here.
Please note that this Terms of Use system uses cookies. If you have cookies disabled you will not be able to accept the agreement. If you delete our cookies you will need to re-accept the Terms of Use.
  • The Department of Art Conservation
  • 303 Old College
  • University of Delaware
  • Newark, DE 19716, USA
  • Phone: 302-831-3489
  • art-conservation@udel.edu