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FWinwood
02-19-2014, 08:59 PM
Hi, after I apply a glaze onto my painting, the colour of it always fades by the time I pick it up a few days later to work on it again, I was wondering if anyone knew why and how I could prevent it?

I am putting my painting against the wall to prevent dust from sinking into the wet glazes while it dries, but I am working in a bedroom with quite a lot of furniture..

Gigalot
02-20-2014, 04:39 AM
As I think, your painting surface is not dried enough, or you ,also, tried to use too much medium for glaze. Let you painting to dry two weeks, then rub couch medium (linseed oil + 10% damar varnish is good enough) onto surface and try to glaze with a minimum possible amount of medium. Pure paint without any medium is the best choice - paint keeps it's original brightness and luminosity. You can try a minimum amount of pure oil (it makes a good sheen) or a minimum liquin (better body and transparency) you can use to give workable, rope and creamy consistency for paint. Do not use any solvent in glaze medium, it makes matte paint film.

FWinwood
02-25-2014, 02:46 PM
As I think, your painting surface is not dried enough, or you ,also, tried to use too much medium for glaze. Let you painting to dry two weeks, then rub couch medium (linseed oil + 10% damar varnish is good enough) onto surface and try to glaze with a minimum possible amount of medium. Pure paint without any medium is the best choice - paint keeps it's original brightness and luminosity. You can try a minimum amount of pure oil (it makes a good sheen) or a minimum liquin (better body and transparency) you can use to give workable, rope and creamy consistency for paint. Do not use any solvent in glaze medium, it makes matte paint film.

Thanks, I've read that I shouldn't use damar varnish for glazing? Do you know any other varnishes I can use? Also, why do I mix varnishes with the medium in the first place?

FWinwood
02-25-2014, 02:52 PM
Gigalot, does the amount of medium I use only matter because the painting underneath may not be dry? For example, could I use a whole bottle of medium over one layer, provided that that layer was completely bone dry? Or do I have to follow the fat over lean rule for each new glaze to be effective?

Mythrill
02-25-2014, 05:34 PM
Hi, FWinwood! When you say your colors fade, do you mean they start disappearing or do you mean they becomes less intense as they dry?

FWinwood
02-25-2014, 06:01 PM
Hey, I mean they become less intense, although it could be that they disappear and the colours I see after a few days of drying time are actually the ones from the previous layer I painted..

kinasi
02-25-2014, 06:38 PM
Cracks can appear years after a painting was painted, you need to follow the

-fat over lean
-slow drying over fast drying
-thick over thin

rules if you want to keep your paint from cracking

you shouldn't throw "a bottle of medium" on your painting so to speak, don't use more than 20% medium to tube paint, most ppl use way too much medium

if a painting gets dull, it's sometimes because the ground is very absorbent, you can bring a painting back to life by oiling it out or varnishing it

FWinwood
02-25-2014, 07:17 PM
Cracks can appear years after a painting was painted, you need to follow the

-fat over lean
-slow drying over fast drying
-thick over thin

rules if you want to keep your paint from cracking

you shouldn't throw "a bottle of medium" on your painting so to speak, don't use more than 20% medium to tube paint, most ppl use way too much medium

if a painting gets dull, it's sometimes because the ground is very absorbent, you can bring a painting back to life by oiling it out or varnishing it

Hi

Do fatter layers dry slower? What do you mean by ''thick over thin'', more tube paint?

Do I oil out a painting by spreading medium over the canvas? Also, I've read that varnishes are only used to add a final effect on the picture, and that's after it's had six months to dry..?

kinasi
02-25-2014, 07:35 PM
Hi

Do fatter layers dry slower? What do you mean by ''thick over thin'', more tube paint?

I was speaking hypothetically, but how do I measure 20%?

Do I oil out a painting by spreading medium over the canvas? Also, I've read that varnishes are only used to add a final effect on the picture, and that's after it's had six months to dry..?
*physically thicker paint...the actual "diameter of the paint film...influences drying...the "thicker" it is the slower it dries...that is the "thick over thin rule"...yes usually the later layers are more tube paint...which usually makes them thicker already

*well, you don't need to measure the 20%, just eyeball it, see how much medium you're adding to your pile of paint

*oiling out is rubbing a medium over your touch dried painting with a piece of cloth, the reason you oil out instead of simply varnishing it, is because even if you restore the gloss back with varnish, not all areas will have the same gloss, which is very offputting, after you oiled it out, then you varnish it, which will result in an evenly distributed gloss

*normally 6 months is the "rule", but it all depends on how thick your paint was, how much medium you used, etc, some alla prima painters varnish after 1 day, it all depends, how much risk are you willing to take, does a client need the painting sooner, do you just want to play it safe, etc, 6 months is playing it safe, if you have time, leave it to dry for 6 month

FWinwood
02-25-2014, 07:52 PM
*physically thicker paint...the actual "diameter of the paint film...influences drying...the "thicker" it is the slower it dries...that is the "thick over thin rule"...yes usually the later layers are more tube paint...which usually makes them thicker already

*well, you don't need to measure the 20%, just eyeball it, see how much medium you're adding to your pile of paint

*oiling out is rubbing a medium over your touch dried painting with a piece of cloth, the reason you oil out instead of simply varnishing it, is because even if you restore the gloss back with varnish, not all areas will have the same gloss, which is very offputting, after you oiled it out, then you varnish it, which will result in an evenly distributed gloss

*normally 6 months is the "rule", but it all depends on how thick your paint was, how much medium you used, etc, some alla prima painters varnish after 1 day, it all depends, how much risk are you willing to take, does a client need the painting sooner, do you just want to play it safe, etc, 6 months is playing it safe, if you have time, leave it to dry for 6 month

Okay, thanks :)

Mythrill
02-25-2014, 11:07 PM
Hey, I mean they become less intense, although it could be that they disappear and the colours I see after a few days of drying time are actually the ones from the previous layer I painted..

FWinwood, the reason they become less intense is because some of the oil evaporates out of the paint when it dries. It happens with watercolors and acrylics as well. There's no "cure" to this, as it's how the paint naturally behaves. Here are some things you can do:


Paint a transparent color over an opaque color, so that color will itself work as an "enamel." That's called "glazing."
Study objects very carefully, making them look more contrasted. This will make colors seem more intense.
Paint using more "intense" colors (e.g, try "Azo Yellow Medium," PY74 instead of "Cadmium Yellow Medium," PY35.)
Avoid dulling down colors with their complementaries whenever you can, as they dull down faster. You can try mixing black (any) with reds, blues and greens. To make a yellow "darker," mixing it with a deeper yellow, orange or red.
If you sense you are using too much black and you're still getting your colors too dull, try mixing it with a brown color, like Raw Umber (Pbr7.) It will darken your colors, but it won't gray them as much as black (any) does.
When you varnish your painting, use gloss varnish. I don't like using it myself, but people usually love the "enamel" feel it gives. 1-2 layers should be enough.

Gigalot
02-26-2014, 04:08 AM
Thanks, I've read that I shouldn't use damar varnish for glazing? Do you know any other varnishes I can use? Also, why do I mix varnishes with the medium in the first place?

You can also use Venice Turpentine or Canada Balsam to prepare adhesive couch medium. COUCH medium is not a regular medium, it is a surface modifier.
It is mostly Oil/resin mixture. 70% Linseed oil +30% Canada Balsam or 80% Oil+ 20% Venice turpentine e.t.c. Resin Just adhere very well. Or you can try to rub just pure oil.

For regular painting and glazing you can try Liquin. Liquin is the best anti-crack (!) medium. Using this medium you can forget about "fat over lean" completely. Glaze is always "thin over thick". So you can forget about the second rule "thick over thin" :D Use liquin, it prevents "cracks"

I agree with Kinasi, you are using very absorbent surface or you tried to paint over not normally dried paint film. Your paint sunk (lost it's oil binder).

the colours I see after a few days of drying time are actually the ones from the previous layer I painted..

It seems to be a "student paint syndrome". Your paints are too much transparent. Try to use less medium plus more opaque and highly pigmented paints. Titanium white, Cadmium yellow, Cadmium red, Indian Red, Chromium Oxide green, Mars Black e.t.c. These pigments have a less tendency to sink.

"In the early stages of my glazing operation, I rub some medium onto the surface of the dried underpainting, and then I apply full-bodied paint into this couch of applied medium, using the medium as a lubricant for the paint, rather than as a "thinner" or a "diluent"."

kinasi
02-26-2014, 08:04 AM
Damar varnish as a medium is going to yellow your painting if you use it like most ppl do.

1/3 damar, 1/3 linseed, 1/3 thinner, is what some ppl use, but besides the fact it smells like death, it also yellows high key paintings. Both the linseed and damar yellow colors. W&N says their dammar should not be used a medium.

I don't like damar as a medium at all.

Liquin is better too imo.

FWinwood
02-26-2014, 03:22 PM
Thanks for all of the comments, I'm pretty sure the problem was that I wasn't letting the paintings dry enough before applying the next glaze.

Just out of interest, how many glazes do you usually use?

Gigalot
02-26-2014, 04:41 PM
Just out of interest, how many glazes do you usually use?

I always try to do the minimum possible layers.

FWinwood
02-26-2014, 04:49 PM
I always try to do the minimum possible layers.

Okay, this might be a stupid question, but how do I tell whether a painting is suitably dry for the next glaze? Iv'e noticed that when I brush my fingers over the canvas the paintings feels dry, but when I press my fingers down and take them off the canvas, there's a kind of sticky feeling, as if the painting were still wet..?

kinasi
02-26-2014, 05:29 PM
I glaze(d), passt tense

don't have the patience anymore, all of my stuff is alla prima now

kinasi
02-26-2014, 05:44 PM
Okay, this might be a stupid question, but how do I tell whether a painting is suitably dry for the next glaze? Iv'e noticed that when I brush my fingers over the canvas the paintings feels dry, but when I press my fingers down and take them off the canvas, there's a kind of sticky feeling, as if the painting were still wet..?

paintings don't fully dry for months, you should be using soft brushes for glazing, so you don't push into the paint, if your layer below it doesn't interfere with your new paint, well, it's ready

usually after a day you can glaze a new layer on, but it depends on how thick you glaze, the humidity of the air, etd

kinasi
02-26-2014, 05:52 PM
if faster drying matters to you, the drying is completely depended on the oil that has to dry, there are faster drying oils like cold pressed and fast drying linseed, or liquin, liquin can dry very fast

Mythrill
02-26-2014, 07:40 PM
Okay, this might be a stupid question, but how do I tell whether a painting is suitably dry for the next glaze? Iv'e noticed that when I brush my fingers over the canvas the paintings feels dry, but when I press my fingers down and take them off the canvas, there's a kind of sticky feeling, as if the painting were still wet..?

FWinWood, as a rule of thumb (correct me if I'm wrong, everyone,) you should wait until your paint is dry to the touch, which is usually around a couple of days (a week, at most, if you paint thinly.) Specifically, when it comes to oils, the next layer should be a bit thicker than the next. I think it was Gigalot that said here on this forum that Liquin is an anti-cracking medium, so it seems you can worry a bit less about this rule if you use it.

Regarding how many layers you should use... well, you can easily go up to 7 layers in oil paint but the less you need to use, the better, so your painting won't crack or delaminate. I paint in acrylics, mostly, so the fat over lean rule has no meaning in this medium I exploit that to my advantage as much as possible, as they can be particularly hard to blend, especially on a hot climate such as from where I live.

Gigalot
02-27-2014, 05:57 AM
Old Flemish masters invented seven-layered technique to paint their Still Life paintings. Their rule sounds "seven layers with seven weeks to dry each layer".
These paintings are still in the best conditions. But you need a lot of time to wait...
You can try to paint 3-4 painting at once. So, you can work on the second painting when first painting dries.. (liquin also can shorten drying time)

Bouguereau invented a quick layered technique. He worked very quickly. The secret is in his medium. He used much siccative and much damar. Damar gives solubility to paint. He worked over four-hours, very soft dried paint layers, and new layer interlock with down layer because it's turpentine dissolve damar into downlayer.
His paintings are now in medium conditions, some paintings have a little cracks on the surface. The key of his technique is siccative and solubility of damar.
But he used top-quality damar. His painting mostly keeps color well, do not yellow.
I think, Salvador Dali did the same thing. In his memories he often talked about "next day color sinking", he used a potato juice and much natural resin he called "ambre' to prevent sinking. I guess, he used a lot of mastic resin or something very close. I heart about Garlic juice which old masters used among layers to prevent sinking and said it can adhere well.