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Old 08-02-11, 05:43 PM
Silver Lining Silver Lining is offline
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Default New Egg Tempera questions (Varnishes,etc.)

Hello Everyone,
Great to find this site.
I have been a painter for a few years but am looking at Tempera because I have issues with solvent in oil paints and have just developed a chemical sensitivity to acrylics (very bad headaches and sinus problems). I am starting to look for another medium so am getting into watercolor and very interested in Tempera.

Any feedback to the following questions would be greatly appreciated.
1) I don't have any egg allergies and setting aside the potential toxicity of certain pigments, has anyone developed a sensitivity to working with Tempera?
2) I have been reading Mayer's book (An Artist Studio Manual) on Tempera and he says you can varnish it the same way/material that you varnish an oil painting. Has anyone here varnished their ET paintings? I really love a glossy look varnish look if possible.
3) When people talk about glazing with ET do they just mean thinning down the ET medium so that it is a very translucent layer?
4) I would like to do rabbitskin over Russian Birch cradles. Anyone have any issues with the Russian Birch? I read an early post but it wasn't clear to me if it was a go or no go.
5) If I stick to tube tempera, can one work with it like oils/acrylics or in a painterly way?
6) I like to work with thin translucent washes, can that be done with ET? 7) Can you combine ET with watercolors and gauche? If so, does it need to be varnished when done on a panel?

Thanks so much for any thoughts and/or comments.

Best,
Silver

Last edited by Silver Lining; 16-06-11 at 08:52 PM.
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Old 12-02-11, 04:08 AM
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Koo Schadler Koo Schadler is offline
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Hello Shea,

1) I haven't heard of anyone developing a sensitivity to egg tempera. As you note, some pigments are toxic (some more, some less). All pigments - both toxic and nontoxic - in their powdered form can irritate the lungs, and working with a lot of powders (powdered pigs as well as the dust that comes from sanding a true gesso panel) can lead to lung problems such as a chronic cough. So be careful with powders (its one of the reasons most painters convert their powdered pigments to pastes before working with them).

2) I varnish my tempera paintings. There are a lot of different options - by and large, anything that can be used to varnish an oil painting may be used on a tempera. Depending on the varnish, it can be applied in as little as a couple of weeks after completing a tempera (i.e. retouch varnishes) or you must wait 6 months to a year for the painting to cure (i.e. final picture varnishes). Most varnishes mean you can no longer work with tempera on top (however some people consider a layer of egg yolk medium a type of varnish, and you could continue to work on top of that.)

There are some tempera artists who object to varnishing, as it covers the soft, lovely egg shell shine that comes from a pure tempera finish; a varnish will also saturate the darks and thus change a painting's value structure, which some artists also object to. You may actually read that one should never varnish a tempera painting - but this isn't factually correct; it is merely, I believe, a personal choice whether or not to varnish, dependent on one's goals as a painter. Many Renaissance painters varnished their work for the saturation and protection that a varnish provides.

The one problem I've run into when varnishing temperas is that the varnish doesn't always dry perfectly evenly - sometimes two coats are necessary to get it so. I think this is due to the great absorbency of a true gesso panel, which doesn't let a varnish lie flat, so to speak.

There is much more that could be said about varnishes (types, pros, cons, etc) but this is already going to be a long posting...

3) A glaze is a transparent layer of color. The best colors for glazing are the ones that are inherently transparent - if you could enlarge a particle of it and hold it up to the light, it would look like a piece of stained glass, with light passing through it, such as Viridian, the quinacridones, Prussian, Thalos, etc. So these are the best colors to use for glazing - and the more thinly you apply them, the more transparent they appear. Once you've tempered your paint properly (got the correct ratio of pigment to egg) you can add more or less water to thin the paint. You don't have to thin transparent colors for them to be glazes - but they glaze more readily when you do so.

However in tempera nearly all colors - opaque and transparent alike - are thinned with water and applied thinly; so that even opaque colors often behave like a glaze. What I mean is that the paint is often so thin in tempera (relative to other mediums) that, even if light cannot pass through opaque pigment particles, light can pass around them when they are sufficiently dispersed, and thus even opaque colors can be, so to speak, "glazed". Hope that isn't too confusing.

Once you get the proper ratio of pigment to egg, you do not need to add more egg to make a glaze. Adding water is the proper way to thin tempera paint (the only exception being that if you add really a lot of water to your tempered paint, you may want to add just a touch more egg, in case the egg binder is getting too dispersed with all that extra water).

4) I'm not sure what you mean by Russian birch cradles. If you mean birch plywood panels that have been cradled, as far as I know birch (or high grade cabinet) plywood is a good support. However I would recommend putting a layer of linen between the plywood and true gesso, as the grain of the wood veneers may telegraph through and eventually lead to cracking in the gesso and paint layers. (I recently saw this on a 40 year old tempera painting on plywood - it was falling apart along the lines of the plywood's grain pattern).

5) Tube egg tempera paints are actually "tempera grassa" ("fat tempera"). While perfectly archival paints they are not pure tempera, as they have a percentage of oil added to them. They behave somewhere in between pure egg tempera and oil paint - so yes, you can be more painterly with them, to a degree.

6) As mentioned above, almost all egg tempera paint is applied thinly. Large washes are a bit tricky to achieve (that is, if you want them to appear consistent). There are different ways to go about it. One technique is called petit lac, in which a "puddle" is laid down in a controlled way. I use a cosmetic sponge to apply large thin washes. Other tempera artists create the effect of a large wash with countless tiny brushstrokes. It can be done in various ways, but I think most tempera artists would agree that it takes practice.

7) Yes, you can combine egg tempera with watercolor or gouache, but you will have a bit of extra binder in your paint (the gum arabic in the wc & gouache). So if you are going to do so, you should cut back just a bit on the amount of egg added or else the paint will feel greasy.

Do you have a specific reason for combining the two mediums? I know sometimes people want to experiment with egg tempera but don't yet want to invest in powdered pigments, so they play with their tube watercolors and egg instead. I think this is a fine way to start out, but just be aware that the paint won't have quite the same working properties as pure egg tempera. There is nothing like just egg yolk, pigment, and water.

No, you do not have to varnish a watercolor-mixed-with-egg-yolk painting, as the egg is sufficient binder, and if left to cure and then polished will give a nice, soft shine (that is, if the paint has been properly tempered). However you could varnish it it you wanted to (see #2 above!) Just be sure that whenever you use egg yolk as a binder you apply it to a fairly rigid surface (true gesso panel or paper that is mounted on an inflexible support) as egg yolk gets brittle as it ages (unless, of course, making it archival isn't relevant).

Well, that's a lot of talk, but you asked a lot of questions! They were all good ones. Happy tempering.

Koo

Last edited by Koo Schadler; 13-02-11 at 01:13 AM.
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  #3  
Old 12-02-11, 12:27 PM
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Bumpkinboy Bumpkinboy is offline
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Koo, you give the BEST answers. I enjoy them so.

Re: the linen lining on top of Baltic birch. Is this a piece of linen canvas you're talking about? Or a linen cloth of some sort? And how would you adhere it to the panel? -- only thing I can think of is an acrylic medium, which I suspect is a no-no.

Thanks!
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Old 12-02-11, 09:58 PM
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Yes, Koo, you give great answers.

""tempera grassa" ("fat tempera")", knew there was oil and usually some type of preservative, but didn't know the term. Thanks.

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Last edited by Bron; 12-02-11 at 10:01 PM.
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Old 12-02-11, 10:04 PM
Silver Lining Silver Lining is offline
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Wow, Koo, thank you so much for your generosity. I can't believe what a well composed and lengthy reply you created. I really appreciate it.

I just received a book from our library called New Tempera Painting. It is new via 1973 but has some great advice in it. I am also reading Ralph Mayers book and has quite a bit of info in it as well but more from a traditional approach.

Is Rabbit skin sizing and gesso dust bad even if one wears a mask? I try to stay away from sanding as much as possible but it looks like t he only way to work with traditional gesso. I am more worried about trying to contain the dust in my studio.

Is the re-touch varnish you mentioned the one you can put on in two weeks? If so, does it have any harmful chemcials in it (or is there a less-toxic version available)?

I found a couple of companies that make pre-mixed dispersion pigments (Guerra and Natural pigments) and may go that route to minimize working with powders -though they are very expensive.

Yes, I meant Russian Birch plywood (1/4"). I just picked up some untempered masonite (smooth on one side and textured on the back - 1/8" thick) and glued up some on cradles to experiement with natural gesso. I will try the linen on top and see if I can get it smooth enough. One thing I would like to do is silver-leafing with the tempera and I am not sure if I could get the gesso on linen smooth enough over the plywood. Maybe lots of coats of sanded gesso would get there. I would like to 'varnish' or seal over the silverleaf and Tempera paint when done and may want to tint the varnish.

I am interested in using watercolor and gaouch to get a good color range (including very dark colors), transparency and to not have to work with dry pigments. I am interested in combining them with tempera medium to reduce the lifting of the colors when I layer them as well.

Thanks Koo, again for your input.

Best,
Shea





Quote:
Originally Posted by Koo Schadler View Post
Hello Shea,

1) I haven't heard of anyone developing a sensitivity to egg tempera. As you note, some pigments are toxic (some more, some less). All pigments - both toxic and nontoxic - in their powdered form can irritate the lungs, and working with a lot of powders (powdered pigs as well as the dust that comes from sanding a true gesso panel) can lead to lung problems such as a chronic cough. So be careful with powders (its one of the reasons most painters convert their powdered pigments to pastes before working with them).

2) I varnish my tempera paintings. There are a lot of different options - by and large, anything that can be used to varnish an oil painting may be used on a tempera. Depending on the varnish, it can be applied in as little as a couple of weeks after completing a tempera (i.e. retouch varnishes) or you must wait 6 months to a year for the painting to cure (i.e. final picture varnishes). Most varnishes mean you can no longer work with tempera on top (however some people consider a layer of egg yolk medium a type of varnish, and you could continue to work on top of that.)

There are some tempera artists who object to varnishing, as it covers the soft, lovely egg shell shine that comes from a pure tempera finish; a varnish will also saturate the darks and thus change a painting's value structure, which some artists also object to. You may actually read that one should never varnish a tempera painting - but this isn't factually correct; it is merely, I believe, a personal choice whether or not to varnish, dependent on one's goals as a painter. Many Renaissance painters varnished their work for the saturation and protection that a varnish provides.

The one problem I've run into when varnishing temperas is that the varnish doesn't always dry perfectly evenly - sometimes two coats are necessary to get it so. I think this is due to the great absorbency of a true gesso panel, which doesn't let a varnish lie flat, so to speak.

There is much more that could be said about varnishes (types, pros, cons, etc) but this is already going to be a long posting...

3) A glaze is a transparent layer of color. The best colors for glazing are the ones that are inherently transparent - if you could enlarge a particle of it and hold it up to the light, it would look like a piece of stained glass, with light passing through it, such as Viridian, the quinacridones, Prussian, Thalos, etc. So these are the best colors to use for glazing - and the more thinly you apply them, the more transparent they appear. Once you've tempered your paint properly (got the correct ratio of pigment to egg) you can add more or less water to thin the paint. You don't have to thin transparent colors for them to be glazes - but they glaze more readily when you do so.

However in tempera nearly all colors - opaque and transparent alike - are thinned with water and applied thinly; so that even opaque colors often behave like a glaze. What I mean is that the paint is often so thin in tempera (relative to other mediums) that, even if light cannot pass through opaque pigment particles, light can pass around them when they are sufficiently dispersed, and thus even opaque colors can be, so to speak, "glazed". Hope that isn't too confusing.

Once you get the proper ratio of pigment to egg, you do not need to add more egg to make a glaze. Adding water is the proper way to thin tempera paint (the only exception being that if you add really a lot of water to your tempered paint, you may want to add just a touch more egg, in case the egg binder is getting too dispersed with all that extra water).

4) I'm not sure what you mean by Russian birch cradles. If you mean birch plywood panels that have been cradled, as far as I know birch (or high grade cabinet) plywood is a good support. However I would recommend putting a layer of linen between the plywood and true gesso, as the grain of the wood veneers may telegraph through and eventually lead to cracking in the gesso and paint layers. (I recently saw this on a 40 year old tempera painting on plywood - it was falling apart along the lines of the plywood's grain pattern).

5) Tube egg tempera paints are actually "tempera grassa" ("fat tempera"). While perfectly archival paints they are not pure tempera, as they have a percentage of oil added to them. They behave somewhere in between pure egg tempera and oil paint - so yes, you can be more painterly with them, to a degree.

6) As mentioned above, almost all egg tempera paint is applied thinly. Large washes are a bit tricky to achieve (that is, if you want them to appear consistent). There are different ways to go abut it. One technique is called petit lac, in which a "puddle" is laid down in a controlled way. I use a cosmetic sponge to apply large thin washes. Other tempera artists create the effect of a large wash with countless tiny brushstrokes. It can be done in various ways, but I think most tempera artists would agree that it takes practice.

7) Yes, you can combine egg tempera with watercolor or gouache, but you will have a bit of extra binder in your paint (the gum arabic in the wc & gouache). So if you are going to do so, you should cut back just a bit on the amount of egg added or else the paint will feel greasy.

Do you have a specific reason for combining the two mediums? I know sometimes people want to experiment with egg tempera but don't yet want to invest in powdered pigments, so they play with their tube watercolors and egg instead. I think this is a fine way to start out, but just be aware that the paint won't have quite the same working properties as pure egg tempera. There is nothing like just egg yolk, pigment, and water.

No, you do not have to varnish a watercolor-mixed-with-egg-yolk painting, as the egg is sufficient binder, and if left to cure and then polished will give a nice, soft shine (that is, if the paint has been properly tempered). However you could varnish it it you wanted to (see #2 above!) Just be sure that whenever you use egg yolk as a binder you apply it to a fairly rigid surface (true gesso panel or paper that is mounted on an inflexible support) as egg yolk gets brittle as it ages (unless, of course, making it archival isn't relevant).

Well, that's a lot of talk, but you asked a lot of questions! They were all good ones. Happy tempering.

Koo

Last edited by Silver Lining; 12-02-11 at 10:10 PM.
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Old 12-02-11, 10:05 PM
Silver Lining Silver Lining is offline
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From what I have been reading (have not done it myself) some folks use PVA acid neutral glue (book-binding glue) to do this.

Quote:
Originally Posted by Bumpkinboy View Post
Koo, you give the BEST answers. I enjoy them so.

Re: the linen lining on top of Baltic birch. Is this a piece of linen canvas you're talking about? Or a linen cloth of some sort? And how would you adhere it to the panel? -- only thing I can think of is an acrylic medium, which I suspect is a no-no.

Thanks!
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Old 13-02-11, 01:51 AM
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Thanks Silver Lining (now - to find bookbinding glue here in the boonies .... hah).

Any ideas on what kind of linen we're talking about? I have a bunch of the Baltic Birch panels and would like to do it right. I have linen canvas, but not sure if that's what Koo meant.
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Old 13-02-11, 02:42 AM
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Koo Schadler Koo Schadler is offline
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Hello again,

I'm supposed to be working on my email mailing list which is a complete snore, so I'm happy to be distracted by more tempera talk.

Regarding covering a wood or plywood panel with cloth, you could use either cotton or linen. There is a discussion of the difference between the two at this link:

http://painting.about.com/od/artsupp...ing-canvas.htm

I've used rabbit skin glue to attach linen to a panel before, and it works well - however I don't see why you couldn't use a PVA glue as Shea suggests. And Bumkinboy, if you aren't concerned about longevity, you needn't cover your plywood at all - it generally takes a while for the grain to telegraph through (depends on quality of plywood, atmospheric conditions, etc). You do not need to cover hardboard (i.e. Masonite) with cloth as there is no grain to telegraph through.

You are correct, Shea, that in order to get a perfectly smooth surface on a panel and cloth support you have to build up more gesso atop the cloth to fill in the weave, but it shouldn't take too many more layers. I usually apply 7-9 coats of gesso and either that, or a few more, should suffice. Don't try to take a shortcut by applying your gesso more thickly as it tends to crack, takes longer to dry...in other words, not worth it. By the way, I don't bother sanding every coat of gesso - after all, whatever smoothness is achieved is then covered up by the next coat of gesso. I sand only the final coat - saves time. I rarely work with cloth on panels (since I use hardboard), so I'm not conversant on this topic (my usual wordiness notwithstanding!). There are other et artists who know more and may chime in.

I believe the book you are referring to Shea is Robert Vickrey's book - it is excellent and one of my favorites. Mayer's chapter on tempera is good too, but I would not recommend his gesso recipe. I find it hard to follow, and (due to the glue ratio) is prone to cracking. I have a gesso recipe I'm happy to share if you need one.

As far as I know, there is nothing toxic in Rabbit skin glue (unless you're a vegetarian!). The "inert white substances" used in gesso (which would be either a chalk or gypsum - there are lots of different names that they go by) are by and large not toxic either; however there are some varieties of chalks that have silica in them and this can seriously irritate the lungs and even cause lung cancer (silicosis). The particles are so fine that a dust mask is not adequate. You need a respirator. Most hardware stores carry only large sizes (for guys) but they can order a smaller size for you if necessary. You need to change the cartridges on occasion.

The subject of varnishes is long and complex. There are so many out there: some store bought, others homemade, some non-toxic, others toxic, some applied with a brush, others sprayed, all with benefits and drawbacks. I have yet to find one I am fully satisfied with. A retouch varnish just means you can apply it before a painting has fully cured (within a few days to a month, depending on the retouch varnish in question). They generally are not removable (and hence conservators dislike them) because they meld with the not-yet-cured, underlying paint layers. A final or true picture varnish can be applied only to a fully cured painting (for egg tempera, this means it has dried for at least 6 - 12 months). Final varnishes are removable (and thus preferable...but not everyone can afford to wait that long).

To pick a varnish you need to know (1) how soon you want to apply it (or, how long can you afford to wait!) (2) how soon you need it to dry (some dry within seconds; some take weeks to cure and can attract dust so they must be covered), (3) gloss, satin, or matte (4) how much yellowing you are willing to tolerate - oh gosh, I could on. I don't really enjoy the subject of varnishes - too confusing and unsatisfying for me. If you can give me an idea of what you want it to accomplish, I might be able to suggest something - but then again I'm not an expert on varnishes and may not be able to help after all!

Dispersions are fine but more expensive, as you note. They have a few minor additives in them (to keep them dispersed and mold/bug free) which, if you've worked with pure, homemade pigment pastes for years, are discernible - I don't like how they feel. But if you haven't developed this sort of bias, they should feel and work fine. If you really fall in love with egg tempera, in time you will learn how to make your own pigment pastes which eliminates the dust problem. They really don't take that much effort to make, except in the beginning, because anything new can feel awkward and strange - but over time its no big deal.

Pigments are pigments, whether they are in house paint or automotive paint or artists paint - so the value, chroma, transparency/opacity, etc. of a pigment is, more or less, consistent regardless of the paint it is in (however the medium, or binder, may affect those things slightly). Hence the pigments in your watercolors are the exact same pigments used in tempera, and any color you can get in watercolor you can get in its raw, powdered form to use in tempera - in other words, the darks are all the same darks. Both tempera and watercolor have a lower refractive index than oil, so you can not get quite as deep a black in those mediums as you can with oil (unless you varnish them at the end, which saturates the paint and raises the refractive index). Similarly, the transparency of a pigment in watercolor is pretty much the same as in tempera. So I think the only thing your tube watercolors are gaining for you is that you don't have to deal with powdered pigments - which may be sufficient reason for you to use them.

Okay, back to work....

Koo

Last edited by Koo Schadler; 13-02-11 at 02:47 AM.
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Old 13-02-11, 03:10 AM
Silver Lining Silver Lining is offline
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Another really great response, Koo. Thanks. I am distracting myself from work also.

I just bought a pound of Rabbit Sking Glue from Utrechts. I hope it is ok quality - it doesn't say where it is from. I also bought whiting from Daniel Smiths but it is really expensive ($7.50 a pound). Is there another name that whiting goes under so I can buy it at a hardware or ceramics store?

I would love to have your gesso recipie. Thanks for the heads up on Mayers recipie. I was going to use the one posted on this webiste but would love to see yours.

As far as varnishing - I really love the glossy look. I know it it counter to tempera and I may end up falling in love with the look of Tempera by itself when I finally actually do one

Anyway, my goal is to have a quicker varnish that is as non-toxic as possible (I'm chemically sensitive and why I happened to come to Temera). If I am playing with fire, I will just have to leave the varnish off but I do need to find something I can put on the painting to seal the silver leaf. I couldn't wait a year to varnish a piece and would need to do it sooner. I would like it to be as archival as possible (i.e. the varnish must be non-yellowing) but I would be willing to go with something that is non-removable. I bought some damar varnish that is ready-made from Utrechts but when I got home my wife told me it is pretty toxic so I don't think I am going to be experiementing with it. I may look at Golden's MSA but it too has some solvents and Acrylic.

Thanks for the feedback on pigments. Have you found an affordable place to buy quality pigments? I plan on using hue alternates to nasty ones like Cadmiums, etc.

Do you work on Masonite? If so, what thickness of untempered masonite to you use? Do you use the kind that has texture on one side and smooth on the top? How large of panels can you make with it? It seems pretty flimsy and the larger ones I started gluing up last night are 16" x 18" but needed lots of cross cradeling.

So far I really like working on 1/4" Russian Birch panels because they are very stable and I can make large panels with confidence with out too much cross cradeling.

Thanks and hope you get your computer work done.

I am back to mine.

-Shea

P.S. You don't need to respond to the following questions since you have already been so generous with your time but, have you ever tried to mix tempera and silver/gold leafing? If so, what has been your experience? Did you make your own size and sealer? Did you glaze over the leaf with ET medium? Did you use the garlic technique (earlier post on this site) to get it to stick or did it just stick? Thanks.

Quote:
Originally Posted by Koo Schadler View Post
Hello again,

I'm supposed to be working on my email mailing list which is a complete snore, so I'm happy to be distracted by more tempera talk.

Regarding covering a wood or plywood panel with cloth, you could use either cotton or linen. There is a discussion of the difference between the two at this link:

http://painting.about.com/od/artsupp...ing-canvas.htm

I've used rabbit skin glue to attach linen to a panel before, and it works well - however I don't see why you couldn't use a PVA glue as Shea suggests. And Bumkinboy, if you aren't concerned about longevity, you needn't cover your plywood at all - it generally takes a while for the grain to telegraph through (depends on quality of plywood, atmospheric conditions, etc). You do not need to cover hardboard (i.e. Masonite) with cloth as there is no grain to telegraph through.

You are correct, Shea, that in order to get a perfectly smooth surface on a panel and cloth support you have to build up more gesso atop the cloth to fill in the weave, but it shouldn't take too many more layers. I usually apply 7-9 coats of gesso and either that, or a few more, should suffice. Don't try to take a shortcut by applying your gesso more thickly as it tends to crack, takes longer to dry...in other words, not worth it. By the way, I don't bother sanding every coat of gesso - after all, whatever smoothness is achieved is then covered up by the next coat of gesso. I sand only the final coat - saves time. I rarely work with cloth on panels (since I use hardboard), so I'm not conversant on this topic (my usual wordiness notwithstanding!). There are other et artists who know more and may chime in.

I believe the book you are referring to Shea is Robert Vickrey's book - it is excellent and one of my favorites. Mayer's chapter on tempera is good too, but I would not recommend his gesso recipe. I find it hard to follow, and (due to the glue ratio) is prone to cracking. I have a gesso recipe I'm happy to share if you need one.

As far as I know, there is nothing toxic in Rabbit skin glue (unless you're a vegetarian!). The "inert white substances" used in gesso (which would be either a chalk or gypsum - there are lots of different names that they go by) are by and large not toxic either; however there are some varieties of chalks that have silica in them and this can seriously irritate the lungs and even cause lung cancer (silicosis). The particles are so fine that a dust mask is not adequate. You need a respirator. Most hardware stores carry only large sizes (for guys) but they can order a smaller size for you if necessary. You need to change the cartridges on occasion.

The subject of varnishes is long and complex. There are so many out there: some store bought, others homemade, some non-toxic, others toxic, some applied with a brush, others sprayed, all with benefits and drawbacks. I have yet to find one I am fully satisfied with. A retouch varnish just means you can apply it before a painting has fully cured (within a few days to a month, depending on the retouch varnish in question). They generally are not removable (and hence conservators dislike them) because they meld with the not-yet-cured, underlying paint layers. A final or true picture varnish can be applied only to a fully cured painting (for egg tempera, this means it has dried for at least 6 - 12 months). Final varnishes are removable (and thus preferable...but not everyone can afford to wait that long).

To pick a varnish you need to know (1) how soon you want to apply it (or, how long can you afford to wait!) (2) how soon you need it to dry (some dry within seconds; some take weeks to cure and can attract dust so they must be covered), (3) gloss, satin, or matte (4) how much yellowing you are willing to tolerate - oh gosh, I could on. I don't really enjoy the subject of varnishes - too confusing and unsatisfying for me. If you can give me an idea of what you want it to accomplish, I might be able to suggest something - but then again I'm not an expert on varnishes and may not be able to help after all!

Dispersions are fine but more expensive, as you note. They have a few minor additives in them (to keep them dispersed and mold/bug free) which, if you've worked with pure, homemade pigment pastes for years, are discernible - I don't like how they feel. But if you haven't developed this sort of bias, they should feel and work fine. If you really fall in love with egg tempera, in time you will learn how to make your own pigment pastes which eliminates the dust problem. They really don't take that much effort to make, except in the beginning, because anything new can feel awkward and strange - but over time its no big deal.

Pigments are pigments, whether they are in house paint or automotive paint or artists paint - so the value, chroma, transparency/opacity, etc. of a pigment is, more or less, consistent regardless of the paint it is in (however the medium, or binder, may affect those things slightly). Hence the pigments in your watercolors are the exact same pigments used in tempera, and any color you can get in watercolor you can get in its raw, powdered form to use in tempera - in other words, the darks are all the same darks. Both tempera and watercolor have a lower refractive index than oil, so you can not get quite as deep a black in those mediums as you can with oil (unless you varnish them at the end, which saturates the paint and raises the refractive index). Similarly, the transparency of a pigment in watercolor is pretty much the same as in tempera. So I think the only thing your tube watercolors are gaining for you is that you don't have to deal with powdered pigments - which may be sufficient reason for you to use them.

Okay, back to work....

Koo

Last edited by Silver Lining; 13-02-11 at 04:38 AM.
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Old 13-02-11, 05:47 PM
arbrador arbrador is offline
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Default learning from Koo

I see that everyone appreciates Koo's knowledge and generosity. She is way too humble so I'm going to tell everyone who doesn't already know that she's written an amazing comprehensive book on ET which you can order from her website www.kooschadler.com.

For anyone learning or practicing ET Koo's workshops will send you light years ahead in your understanding and practice of the medium. I've gone three times and will continue to learn from Koo.

I had already been practicing ET for about 30 years when I took her workshop and it solved so many dilemmas I had had for years.
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