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ptantono
08-25-2001, 01:16 AM
I have just finished my first oil. I wish to know more about underpainting especially what do you mix with your underpaint. I used kerosine with a little paint, that was what I was told to do.

What else the benefit of underpainting ? I thought it was only for helping the paints to easier apply on the canvas but I learn from Miltz that it is more than that.

Patricia:angel:

Gerauds
08-27-2001, 10:05 AM
There is a lot of information on underpainting here. And there are just as many reasons for underpainting! I'll give you my own reasons and what I use for them, and I'm sure you'll get quite a few more!

I use my underpainting for two reasons: The first is as a reference. I do fairly precise work and I have my subject drawn in detail before I start painting. I transfer this drawing to canvas, then complete an underpainting in raw umber and turpentine, very thin, but dark enough that while I'm painting later, I can still see the lines underneath. That way, I don't lose the details I worked so hard on, and I don't have to re-draw the detailed painting again.

However, I have recently started using the underpainting to confirm my tonal qualities. I do the underpainting in raw umber, white and turpentine. I actually do the entire painting in this monotone. It does a couple things for me. It confirms my tonal qualities (which should have been confirmed in the thumbnails I have done before hand, but extra confirmation is always good). But more importantly, it allows me to worry about the tones of the painting WITHOUT having to worry about the colors yet. I can spend a little time darkening the dark areas of the painting, so that when I start painting this dark base is already there. When I actually get to the colored part, I don't have to worry about as much with making the dark parts dark. They already have that dark base underneath them! (I think I read a great post about this subject here...I'd search for it!)

If you have any more questions on my own reasons, feel free to let me know. But, I'm sure there are a lot more reasons and techniques for the underpainting. I'm pretty eager to hear other techniques!


Geraud Staton; A Leo who likes hot summer days and sweaty nights with the windows open.:angel:

shawn gibson
08-27-2001, 10:15 AM
Kerosine to thin an underpainting? Please enlighten me. I'd'a thought turps, oil of spike, maybe some new turpenoid product...but I thought kerosine was what you use to fuel your lamp?

Luis Guerreiro
08-28-2001, 03:33 PM
The principle of the underpainting is the same of the colour TV.
Pick your remote, remove all the TV colour, re-adjust your brilliance and contrast in black and white. You'll get the grey tone values. This is your first paint lean layer. Now using the colour adjustment button put some colour in, just enough so you can still see the grey underneath, this is your first colour layer, keep building up the colour saturation until you're happy with the result, and off you go, painting in layers explained in just a few lines. Simplistic? Yeah, but that's how someone else explained it to me.
The principle is just so simple that you can get mislead on the relative simplicity of the underpainting itself. This is where experience counts, as practice is different from person to person.
The rules of thumb though should be observed:

For underpainting, always use:
1. White (Cremnitz/Lead white preferred as it dries fast). Safety precautions APPLY IN FULL as this colour is toxic, but if used properly is complete safe and harmless. Lead is a natural siccative and lead white is the less fat of all whites so it helps the observance of the FAT-OVER-LEAN oil painting rule.
2. Earth colours (Raw Umber) + Ivory Black 60/40 % mix
3. Turpentine or a mix (90/10%) of turpentine and stand oil to thin your paint values to the consistency best suited for the painting or part of the painting you're executing. Do not thin them too much to avoid under-pigmentation of the paint.
4. Divide your tonal values in 8 values, the lightest value is pure Cremnitz white and build up the other 7 values up the darkest value (No. 8).

Contrary to some painters (and oil painting books too I'm afraid!!!), your darkest value should not be pure dark. If you are using the above colours, each value up contains more Raw Umber colour mix, but the 8th value SHOULD NOT be just pure Raw Umber mix, but also contain a very tiny amount of Cremnitz White.
The total result should be that although the values are correct, the whole underpainting is somewhat lighter than your subject mater is in reality. This difference will be corrected when building up your colours over it.

If you decide for whatever reason not to use Cremnitz White which is the lead white, very lean, the leanest of all whites and the most beautiful one too and instead use Zinc White or Titanium White, keep in mind that the other colours may have an impact of how the underpainting behaves in which case, greater care must be taken in picking a colour that is quite lean and fast drying. Titanium and Zinc whites are slow drying so the drying rate (and the very lean nature of the underpainting) have to be maintained by other means, such as the colours you will use to mix with the white.

There are many reasons to prefer Cremnitz White. There is a silverish/pearlescent brilliance about it, it integrates with the other colours in a more desirable way, covers well yet is also somewhat transparent it's very lean, i.e. very little oil is needed to make Cremnitz White, the lead preserves tha painting maintaining it flexible and stable. Zinc white is too brittle, Titanium white is too opaque and too white.

Also note that Lead White is usually a reason for "mercurial" magnificent "thunderstorms" over its safety (it is highly toxic and poisonous). Quite some time ago I wrote a health and safety post about lead white (refer to the Hall of Fame) and the effects of lead poisoning. As long as you observe responsible rules on using lead white, it is very safe. But always buy oil TUBE lead white, of which the finest grade is called Cremnitz White, which is Lead Carbonate ground in oil. Never EVER grind lead white pigment manually at home or in the studio, because of the risks involved, the mess it makes and the difficulty in disposing and cleaning up after it. When using tube lead white, protect your hands with latex or vinyl disposible gloves, use protective cream, take care when washing brushes and disposing of rags safely. Usually, local garages feature disposible facilities for environment unfriendly products and in most European countries members of the European Union, lead paints are banned except for artistic and industrial purposes, but provide ways of disposing of lead poisoned rubbish (local councils in the United Kingdom take care of this). Simply collect in a single bin used specifically for this all lead white rubbish and when the bin is full, dispose of it using one of the ways explained above. Lead white MUST be kept away from children and pets (highly vulnerable to lead poisoning), lock the tubes away, safely. It sounds absolutely horrid, but it's not, all it takes is responsible use, care and safe disposal. Apart from this, many if not the majority of professional painters and arts teachers recommend Cremnitz White as absolutely irreplaceable.

Mario
08-29-2001, 07:56 AM
I have found zinc white very disappointing, the only use for it, that I can imagine, would be top layer glazing in the very last stages of a layered approach, the reason being that it is so transparent...
I have much difficulty going from underpainting to the subsequent layers...in that, there seems to be little relationship to the underpainting as I "progress" towards the completed painting...I sometimes wonder why I don't just paint directly...

Gerauds
08-29-2001, 08:26 AM
I almost agree with you, Mario, especially if you paint in thick layers. You only cover up all the work you did previously. I admit, my paints are very thick, at least not in the beginning. The underpainting does nothing more for me than keep me from having to re-draw details that I have transfered to canvas. Since I do portraits, that is very important to me. The tonal reasons I gave above are also good for my work, but I use three levels of tones, not the eight that Luis uses (I've heard people who use 10!) but I think his advice is still great.

Remember, the point is to make your art better, and to enjoy what you do!


Geraud Staton; A Leo who likes going to movies and eating lobster dinners.:angel:

Luis Guerreiro
08-29-2001, 10:53 AM
Mario and Geraud,
Thanks for your posts. I see no reason why one would use the underpainting if really thick layers are to follow.
I use the underpainting whenever my planning for a particular work aims at a smooth finished painting or thin layers are to be built-up. This also applies to modern and abstracts made of areas of colour and "washes", rather than knife impastos or brush stroke relief work.
The number of values can be anything, from 3 values only (used in the old days for drapperies, for instance, I think, but I'm not sure) to 16 values. I find the average of 8 values suitable for most purposes.
Also and as an addition to my previous post, I would suggest the following mixes for underpaintings:

1. CREMNITZ WHITE (the finest grade a MUST).
2. A colour mix made of:
2.1. Raw Umber (Pigment PBr 7), part=60%
2.2. Mars Black (Pigment PBk 11), part=40%
3. A LITTLE Turpentine to thin, I mean a LITTLE. Too much will put the underpaint stability at risk by under-pigmenting it.

My previous suggestion of a colour mix of 60% Raw Umber and 40% Ivory Black is also fine, but last night I went back to my Notebook to check my records and the following applies:

Because the FAT-OVER-LEAN rule MUST be observed to ensure the longevity and stability of the painting, the type of BLACK to be used becomes quite important if one is to make a very LEAN underpainting.
The low content of oil in a particular colour is the reason to choose the above colours for the underpainting.
Raw Umber has been chosen because its drying rate is very fast, however its oil content is medium.
Mars Black drying rate is average, but its oil content is low
Cremnitz White drying rate is very fast and oil content very low.

Conclusion: This mix of Raw Umber+Mars Black+Cremnitz White is of at least FAST drying rate and LOW oil content, which are the characteristics we want for a sound underpainting. On the other hand, Mars Black undertone is brownish, which goes better with Raw Umber.
Ivory Black may be used, but its oil content is HIGH and drying rate SLOW, which makes it just about ok for underpainting. If too much of it is used or the tube colour is too fatty, it can impair the delicate balance of the underpainting. Ivory Black is more transparent though, which is not the case with Mars Black which is opaque, but this may not be crucial.

ptantono
08-31-2001, 08:54 AM
:) THANK YOU VERY MUCH Gerauds, Luis and Mario for your reply. I receive such complete information that I need. Now I know that I knew Nothing about underpainting before getting to know you all.

Shawn,
Yes, I did use kerosine for the underpainting. Mix it with the same color that I will use for the painting later, please dont ask me why ;). I tried to make it better by learning from all of you here :) .

Thanks again All. I am learning a lot from you.

Patricia:) :) :)