Resurrection of a W.I.P

I've been doing a little Spring cleaning lately and came across a few unfinished canvases tucked away. Why I never finished them, I don't know (I look back at my former self a little jealously now when I think of all of the time I had to paint!) But at least a couple of these lost souls seem worth the attempt. Except for some paint and a little more time, what have I got to lose? I decided to work on this painting of the Tuscan hillside first, since the whole canvas  was pretty far along and just needed to be fleshed out a little more.

 oil painting tuscany work in progress

Looking back through my blog archives, I actually posted this as a W.I.P. back in October of '09 (!) According to this post, I was suffering from shoulder tendonitis at the time. I guess between that and whatever else I had going on at the time, this canvas fell out of sight, and subsequently out of mind...until now.

When I first worked on this painting, I used an alkyd medium to speed the drying. So I've started in again by using some of the medium to "oil out" the areas that I want to work on. I've altered the composition slightly by elongating the shadows (it's a dusk scene) and also by simplifying the road in the foreground. It seemed to be moving too fast around the bend and leading me right out of the canvas, so I altered that area slightly by extending the shrubs to slow this movement down. I'm also toning down the yellow in the hillside because the foreground shrubs are meant to be yellow broom, and I want a different color behind them to contrast. As a result,  I'm laying in a lot more of that terra cotta earth so prevalent in this region. We will see how this goes...  A lot more work needs to be done to the hillside, the olive trees, and their shadows, and I may need to add some of the greens back. But for the moment I'm liking the predominately warm tones. I'm working more on this painting this afternoon, so  if all goes well, I hope to post a conclusion by  Friday.

Coastal Sunset Painting- WIP

While the last work in progress I posted still seems to progress I offer you this new WIP that seems to be moving along a little more easily. I have decided to return to the nontoxic (or less toxic, any way) painting process that I was doing while I was pregnant.  Essentially this process was to paint without solvents and instead to thin the paint and clean my brushes with walnut oil.

sunset oil painting work in progress

What was formerly a struggle to me using this method now seems to be working to my advantage. Working with the walnut oil keeps my paintings wetter longer. This is a good thing for me now, as I am only able to get dedicated painting time for about 3 half-days a week. So I can now return to my painting in a more malleable state without having to feel like I need to rework everything in order to open it back up again (which is what kept happening with the Venice WIP). 

sunset oil painting work in progress

I also decided to try working with M. Graham paints again, which I had tried (unsuccessfully) to use en plein air some time ago. Initially I found them rather more fluid than I was accustomed to, particualrly for juicy plein air work that I need to have set up rather quickly. It was also a hot summer day when I last tried to use them, and what I ended up with at that time was a mushy, gooey mess. But, again, what seemed like a liability is now working to my advantage, and I am really enjoying these paints now, for the precise reason that they are more fluid and very buttery.

For this painting I am using a single primary palette of red yellow and blue plus white. For my red I've chosen Quinacridone Rose; my yellow is Indian Yellow, and the blue is my old friend Ultramarine. I am, of course, also using white, which is my favorite white and what I have on hand, made by Classic Artist Oils. It is buttery, but has a little more body to it and blends nicely with the more fluid colors. This is a really good palette, I am finding, for sunset paintings, as the colors are both rich and transparent and lend themselves to that luminous quality I'm after. And since at sunset everything seems to take on the color of the sky, using a limited palette creates a nice unity in the painting.

sunset oil painting work in progress

These pictures show the progression of my 24x30 inch canvas so far. If all goes well, I should be able to finish this piece today for a posting of the final product later in the week. That is, if I can get myself off of this computer!

Bellagio from above; more oil painting w/out solvents

Following up from my prior WIP, here is the final painting. This is a view of Bellagio from a hike we took up to Villa Serbelloni. The villa is now maintained by the Rockefeller Foundation, who uses it as a retreat for  the Bellagio Study and Conference Center for artists and writers (wouldn't that be nice?) For this reason, we couldn't go inside the villa when we visited, but we could tour the grounds, which offers gorgeous views over Bellagio.

Oil painting of Bellagio, Italy

"Bellagio From Above" Oil on Linen, 20x16"


Both this piece and my previous Lake Como painting, were done without the use of solvents or any other medium other than small amounts of walnut oil to clean brushes and thin paint when necessary. But even when used judiciously, the walnut oil served to slow drying considerably. At present this is not a huge problem, as I am spending most of my time painting/renovating/preparing home and life for the new baby! But it does change the nature of things and the overall result became more impressionistic due both to the behavior of the paint, and probably also the gaps in my working sessions.

I know that an oil painting requires a certain length of time for all of the layers to fully dry (sometimes as much as 6 months or a year.) But normally the top layers will dry to the touch in about a week's time.  Not so with the walnut oil method, which seems to require at least an additional week to my usual handling time.

Maybe it's just that my painting habits are not particularly suited for this method, or maybe I just need to get used to new ways of doing things. Overall, except at the very beginning stage, I don't paint in thin layers. In fact, while I don't lay it on with a palette knife, I do paint passages that are relatively thick and juicy. But oddly, I experience the most difficulty in the lay-in, (early stage) which I am used to having set up rather quickly.

First of all, in order to follow the "fat over lean" rule, I have been trying not to make the paint too "fat", too soon. So I keep the walnut oil I use in my initial lay-in stage very spare. The result is that instead of a thinly painted initial sketch and color block-in, I find myself with trying to move paint around that has a definite drag and is less fluid. The lay-in becomes more often a "rub-in" with a rag or a "scrub-in" with an old brush, and the edits and corrections are very hard to lift off the canvas.

On the other hand, if I use more walnut oil at this stage, the paint can get too smeary and unmanageable for successive layers, not to mention less stable (with any medium you use, you should only use no more than 20% total volume when mixed directly into the paint, and I usually err on the side of caution and use rather less than that.)

One solution may be to use a runnier paint in the lay-in stage. M. Graham walnut oil paints are such a paint. I do have a few tubes on hand, as I've tried them in the past. As much as I wanted to like them, I normally prefer more body to my paints. But they might just work for my purposes now--but still probably just in the initial stage only. (Incidentally, it's perfectly okay to mix walnut oil with linseed oil based paint, so even if you want to paint solvent-free, you do not need to buy their paints exclusively.)

Aside from walnut oil to thin,  there are other oils to try. Linseed oil is commonly used by artists, both in mixtures of ground paint and in various mediums. And while both linseed and walnut oils are considered to be "drying oils", linseed tends to be the faster-drying of the two.  However, I seem to read a lot about how linseed oil tends to yellow over time. Maybe this is an exaggerated worry, but a quick look at experiments like this one swayed me to first try the walnut oil over linseed.

So, to sum up from this layperson's perspective, some of the pros of using walnut oil to thin/clean are:

  • Non-yellowing
  • Non-toxic/ solvent-free painting (though other oils can also serve to achieve the same thing.)
  • Odorless
  • Does not evaporate like solvents, so it seems fairly long-lasting
  • Conditions brushes nicely


  • Walnut oil is expensive! (If you are only using oil to clean your brushes, you could probably get by with a less expensive oil.)
  • Slows drying considerably (this could actually be a "pro", depending on your painting technique.)
  • Compared to solvent, it requires using more brushes and/or more wiping of brushes between colors in order to keep the color clean.
  • Walnut oil is expensive!

Another big one

I thought I'd continue my studio work in larger format with another three by four-footer from my trip last year to France. Still at the block-in stage, but things are starting to take shape. I think the little fishing dude at the tip of the "peninsula" will help to give a sense of scale to the line of towering poplars. :

French landscape painting of water by Jennifer Young

Hopefully this WIP will progress a little more quickly than the last one I posted of Beynac. I am finding that the breaks in continuity of my time in the studio also breaks the continuity of the painting for me. I'm not using any medium, but still the paint sets up pretty quickly. Once that happens, it is a lot more work to open things back up again. I haven't been able to manage an alla prima application for larger works like this, and sometimes an interruption in studio time can't really be avoided. But as long as I can work at it on consecutive days, I can work more wet-into-wet; which makes it easier for me to keep it "fresh". So that's my goal for this one--maintaining a continuous flow from start to finish.

Southern France painting demo continues

This post continues a demo I started last week. To start from the beginning, click here!

Before going too much further I like to get a good feel for my area of interest, so I lay in the general colors and highlights of the wall of the Abbey ruins. I've worked wet into wet to blend the purple shadow colors with the warm local colors of the Abbey wall, which gives me a nice mixture of golds, browns and muted violets.

Landscape painting demo by Jennifer Young

At this point I am ready to dig in to the rest of the landscape and get that canvas covered. To keep the flow going, I try not to be "stingy with my paint". For this painting I'm using a somewhat more expanded palette than I do when I paint on location.

oil painting demo by Jennifer Young

I  want to have large enough puddles of the colors I see so that I don't have stop every five seconds to mix up more paint. This process is pretty organic so it's difficult to give a step by step process of mixing colors. In addition to blending paint wet-into-wet on the canvas, I also tend to dip into various larger puddles to make new blends as I go along. The most important thing during this process is just to compare one color, one value to the others, constantly asking myself, "Darker or lighter? Warmer or Cooler?"

french landscape painting demonstration by Jennifer Young

I also decide to indicate the basic iris colors so that I know where I'm at. I have to be careful here--even the middle value of the purple/blue flowers has a lot of white in it, so I really don't want to paint these too thickly or it will be hard to control the darks, making them muddy and less pure. A lot of these preliminary iris lay-ins will need to be restated, and, of course defined, but I felt like I wanted some indication of them in there at this point so I wouldn't get lost (if that makes any sense!)

painting demonstration by Jennifer Young

Here you can see that I've continued on working my way down the canvas so that eventually everything is pretty well laid in. I've held off putting down much of my strongest highlights. That will be among my next steps, along with further refining, defining, tweaking, and adjusting.

paintings of France by Jennifer Young

Up to this point I have used just a few brushes. Aside from the one round I used for the linear drawing of my composition in the earliest stages, I've used my larger flats and filberts. Being the very messy painter that I am, I can't tell you the size numbers of any of these, as there is old smeared paint on all of my handles, completely obscuring any info that once was printed on them! I think probably the smallest in use is around an 8 or 10(flat) but the ones I used the most were the largest filberts I have, with widths ranging from 1 and 1/4" to 1 and 3/4". I love these large filberts, as you get a nice thin edge at the tip and a broad flat side too, making them very versatile for my purposes. I could even stand to go to a larger size brush for this size painting, but I need to conserve my expenses so I'm trying to use what I have on hand right now. Even so, if I use the broad side of the brushes I can get a pretty broad and loose stroke and avoid getting too fussy with too many details too early!

landscape oil painting demonstration by Jennifer Young

To be continued...

Frayssinet Village painting- final edits?

I started this painting some time ago and it's taken me longer than I'd like to bring it to a satisfactory end. I generally dislike having long periods of stops and starts between painting sessions because I end up "oiling out" the painting and I run the danger of losing that freshness that comes with alla prima painting. But we're in the final stages of finishing the new studio so I just have to deal with the back and forth for a little while longer. (BTW, "oiling out" is when you wipe on a thin layer of diluted medium to help a partially dry oil surface better adhere to subsequent layers.)

village painting of southern France by Jennifer Young

This is a 24 x 30" painting of the village of Frayssinet, my "home base" for my plein air painting trip last summer. Photography issues continue, so at least on my monitor the color is a little dark and contrasty and the sky is too yellow and has lost the gradations of pale blue. 

Photography issues aside, the photos do give me a chance to again take a "step back" (something I mentioned before I can't manage to do in my temporary painting space.) With a new perspective, I am considering changing the figure. Right now the proportion makes her a little lost in the painting.

One option is to make her bigger. A quick edit in Photoshop makes this happen. (If only it was that quick and easy in actuality!)

French village painting Jennifer Young

The other option is to take the figure out altogether:

Jennifer Young landscape paintings of France

Of course, the second edit above would be the simplest option and it's not a bad solution. I'm leaning towards changing the figure, however, as she does add a bit more interest and  focal point.  Yeah or nay? No edits? Or edit #1 or #2?

Flying with artist oil paints, plus tips for plein air

As I set out to answer a few questions about traveling with paint from fellow painter Marilyn King, I realized the length of my response was worthy of its own blog post! So Marilyn, thanks for the assignment! :-)  There are a million different approaches, a million different solutions; but here are some ideas: Oil paints; Lighten the load!

While it is more economical to use larger 150 ml tubes, I generally save them for use in the studio. (In fact, for my white and some other colors, I buy in even larger quantities --either in cans or in caulking guns.)  But if you're using a double primary palette en plein air, lugging big tubes of each color can get a little weighty! For this reason, I keep a set of smaller tubes for plein air painting. I generally carry one large 150 ml white out on the field and smaller tubes of the other colors. A couple of other options:

  • Yes, you guessed it--limit your palette. This gets easier to do the more you try it. There are many plein air painters who limit to 3 primaries plus white to get all of their colors. This is Kevin Macpherson's suggestion in his first book on plein air painting, and even in the second one  (though he does get a little more expansive in the latter). A limited palette  does simplify things for plein air.
    • Cadmium yellow light, Alizarin Crimson, and Ultramarine Blue plus white would be one example of a single primary palette. In this case you might even bring larger tubes since you'll have fewer of them. I've often used this palette as stated or supplemented only slightly with one additional color (e.g. a small amt. of phtalo green.)
    • While it can seem pretty limiting at first, a limited palette will create more overall unity in your painting,  it is a very good practice for anyone who is interested in learning about mixing color. 
  •  Squeeze out your colors on your palette before going out to paint. Obviously this won't work if you're flying on a plane! The down side is that most beginning plein air painters don't squeeze out enough paint on their palette to begin with! And even if you're used to painting outside it can still be a challenge to judge how much you'll need.
  • Transfer your colors into smaller containers (again, won't work with flying!)
    • Jerry's Artarama (and probably other art supply stores) even sell empty paint tubes for this purpose.
    • Paint film canisters or other readily available plastic containers could also be useful, though be aware of the depth as it may be a challenge to dig the paint out after a while.  Another option is to find the larger sized pill box containers. You know, the kind that have slots for each day of the week? I did this for a while, but since this is a temporary solution, I eventually got lazy and just bought smaller tubes for plein air.
    • Note: Many plastics may eventually degrade--particularly the lids that are often made of the softer plastic needed for flexibility. I like to leave a plein air "emergency kit" in my car and I have had containers made of softer plastic degrade, warp, ooze and pucker over time. Yuck.

Yes, but what about flying with oils?

For flying, here are some solutions I've gleaned from others and from trial and error:

  • First, I wrap my paint tubes in foam sheeting or bubble wrap to reduce the chance of puncture, and then pack all of my paints in ziplock bags in my checked bag. (You can't bring paints or mediums in your carry on.) 
  • I also enclose MSDS sheets in the bags with my paints, as provided by the manufacturers. These sheets list the flash points for the paints. According to the Gamblin website, artist oil paints contain vegetable oil and no solvent, and you're good to go if your paints have a flashpoint of 140 degrees F (or above). *If bringing a painting medium, check to make sure that it does not have a higher flashpoint before packing it!
  • If questioned by airline security, explain that these are artist's oil colors and have no solvents, and provide the documentation that says the same. It seems the word "paint" can possibly set off undue alarm.
  • Buy turpentine in the destination country (en Francais- "La terebentine"; in Italiano- "La trementina"!)
  • If possible, just bring your tools and supports, and consider buying paints in your destination country. This is actually a lot of fun! If you haven't been in an art supply store in Paris, you owe it to yourself to go any way. I always feel like a kid in a candy shop when I do.
  • If you'll be in a more "out of the way" or unfamiliar location, you might research art supply stores in the area where you'll be going. Did you know that the regional visitor centers are extremely helpful? In the past I've just sent them an email and gotten back a list of stores in the vicinity prior to my departure.
  • Lastly, you just might check into water soluble oil colors. I need to experiment more with these some day. It's hard to beat the tried and true, but WS oil do eliminate a few challenges for the portable studio, and many artists report being pleased with their results.

 Medium or no medium?

 Often times I don't even use a medium for plein air painting because it seems like even with just a little bit of breeze, any kind of alkyd medium gets a "skin" before I can even use it. However, there are times when it is handy; especially if I want to try and hasten the drying time of my paintings.

  • An alkyd based medium (Liquin, etc.) is useful for this, and fairly portable if you can buy it in a small bottle.
  • Another option is Wingel (by W&N) or Lukas Painting Butter, both of which come in tubes. But being more "solid," the tube mediums seem to dry up even faster than the liquids, so the key is to use it sparingly if you're going to use it (a good practice any way).
  • If hastening the drying time is what you're after, you might just look into getting an alkyd-based white for plein air. I have found that when I use Gamblin's "Quick-Dry White" it helps speed up the drying time of my entire painting while still keeping the painting open for a good while.
  • If you are reliant on a medium to increase viscosity (flow), be aware that turps and paint thinner are *not* mediums and should not be used  to thin paint beyond perhaps the very beginning "sketching" stages of your painting. They will weaken the paint film.
  • Again, if you're going to be flying, check the flashpoint before packing the medium! If it's too high, leave it at home and consider doing without or buying it at your destination.

New stuff coming soon, I promise!

I have many notes on things I'd like to blog about, but it seems this whole month has been crammed packed with activity. I'm getting ready for the art walk this Friday, and  a trip to France in just over a couple of  weeks.  But I will post new work this week, even if it's just a few small plein air pieces. And I've plenty of other things I'd like to write about too, if I can find the time:

I may not get to everything, but I will surely get to a number of these topics over the next couple of weeks before I sign off to head for 10 days of computer-free travel.

"Lingering Light, Tuscany" miniature oil painting

More "small stuff" today as I continue preparations for Thursday night's gallery anniversary party and the First Fridays Art Walk that follows. This little painting shows the setting Tuscan sun over a sloping grove of olive trees .  There is a companion to this little painting that I'll try to post soon. 

tuscany sunset miniature oil painting 

 "Lingering Light, Tuscany" Oil on Linen mounted on birchboard Approx. 3.5" x 7.75" sold

It's an odd size, I know, but I do have a frame for it. It would also look great unframed, just perched on a mini easel.

I am enjoying the long horizontal format I've used in these pieces and in my previous painting of Venice. That's the great thing about making small works--you can experiment with formats and compositions (mediums too) with less sweat, tears, and expense than is sometimes required of a large canvas. And if they don't work out, they fit into the trashbin  a whole lot easier! I think this one's a keeper though. ;-) 

Do you Squidoo? My new lens on hanging artwork.

According to Wikipedia,

"Squidoo is a network of user-generated lenses --single pages that highlights one person's point of view, recommendations, or expertise."

According to me, it's pretty addictive! I've really been enjoying surfing it, and I've also created a couple of lenses of my own. My most recent lens is: Hanging Artwork and Caring for Your Art Collection. While I've blogged some of this information before, I've included new content on my lens that I hope will be of interest to art lovers and art collectors. I've also just updated my other lens on landscape painting with new content, so check them out! And if you enjoy my lenses, please consider leaving a star rating for them at the top of the screen.

Mini taboret, palette and art caddy

I made mention the other day about my home made mini taboret that I devised (with the help of my husband's handiwork!)  Here it is:

taboret art cart palette

I use this as my color mixing palette and as a holder for a few of my essentials- my oil paints, any medium, paint thinner and paper towels, etc. The main structure is actually this laundry caddy, that is meant to slide in between a washing machine and drier.

The goal in my search for the perfect cart was to find something ready made that I could use directly in front of my easel as a palette area to mix my paints.

I figured if I didn't want to bend over or reach out too far to get to my canvas, I'd like something no more than 12 inches deep, and at the right height so that I could comfortably mix my paints without having to stoop.  I also wanted something on wheels, so that I could roll the cart to the side if I were painting a very large painting.

What I came up with was this art caddy. The caddy required minimal assembly and was only around 8 or 9 inches deep. I'm not a tall person, but still the cart wasn't quite tall enough for me. This is where the handiwork came in. My husband told me to determine how much higher I'd need the top to be in order to comfortably mix my paints. Once this was determined, he built up the height by engineering a little insert cut from two by fours. Then he attached a 12"deep x 36" long board (a shelf left over from an old IKEA bookcase) on top of his insert. Sitting atop this board, I have  3 12x12" ceramic tiles. This is my paint mixing area. The tiles are backed with velcro so that if I get very vigorous with my mixing they won't slide around.  I'm not great with cleaning my palette thoroughly, but the great thing is these tiles are cheap and easily found at any Lowe's or Home Depot. If they get too dirty then it is easy enough and inexpensive enough to change them out.  A very handy person could probably easily construct the whole caddy from scratch, but being short on time and patience, this cart works for me! And was far cheaper than anything I had looked at that was comercially produced.

Care needs to be taken when moving the cart. In other words, you can't whip it around very quickly as it is slightly top heavy. This is mostly remedied by putting heavy things (like cans of thinner) on the bottom shelf.  I used a simple bungee cord strung from one side handle to the other to hold my paper towels, and the baskets are ones I found at the dollar store. 

A taller person might require a taller cart (I'm 5'4 1/2" tall) so you'd really need to measure everything to make sure this is the solution for you. There are also expensive easels that actually have tiles along the front part of the easel, and this is another option if you want a complete system. However, I rather like having the cart/palette separate as it is a little more flexible for me to have something that is freestanding.

Oil painting; Possible solutions to common challenges

Here is a followup to yesterday's post; "Why paint with oils?"

  • If you can't stand the smell of turpentine, use odorless mineral spirits (OMS) or Turpenoid Natural to thin and clean up. *Be aware though that while OMS is easier on the nose it is no less toxic for those who are sensitive to turps. In that case your best alternative is to clean up with Turpenoid or some other natural product.
  • To avoid "mud", refrain from mixing too many colors together.  Try mixing with your palette knife instead of your brush. This will allow the paint load to sit on the end of the brush and not mush down into the brush toward the ferrules.
  • Avoid the overuse of white. White will lighten values but also cool and dull colors, giving a chalk-like appearance to most colors if overused.
  • Avoid the overuse of black or dark earthtones. Some would say avoid ANY use of black as it is a dead color. With hesitation I will say I have nothing against black if used judiciously. But I usually suggest beginning students keep black off of their palette because there is a tendency to reach for the black (or umber) for anything that requires shading or darker values. This  can result in an overly dull, flat looking painting. If you use a mixture of your darkest primaries and just a touch of a secondary you can achieve much richer, more vibrant darks. Ultramarine + Alizarin Crimson + Viridian or Sap Green will "read as" black but be much richer looking.
  • Avoid over-working back into a wet section. Experiment with laying in your color and leaving it alone as much as possible. Over blending and mushing your paint around on your canvas can lead to  "mud".  If you need to go back into an area either wait until the paint "sets up" a bit, or scrape off and repaint the area.

 Experiment with other mediums:

  • While absolutely no medium is necessary, it's fun to experiment with different painting mediums to enhance the behavior of your oils. There are a variety of mediums available that can help speed drying time, enhance the fluidity of you brush stroke, and help your paint strokes stay where you put them. Liquin is a relatively odorless option that adds viscosity and helps speed drying. Copal medium is incredibly seductive but it does have a very strong odor as it is mixed with turpentine. Galkyd Lite is what I'm using right now. It's very similar to Liquin but not as "slippery". *Note: Whatever you use, a little medium goes a long way.
  • Some people experiment with alkyds. These are oil paints with alkyd resin mixed in, creating a faster drying oil paint. (Down side: they can appear more "plastic looking". Colors aren't as rich and can seem very bright and candy-like. They still clean up with turps or mineral spirits and can be used in combination with regular oil paints.)
  • Some people experiment with water soluble oil paints. These clean up with water, and tend to dry somewhat faster than regular oils. The cleanup can be a real advantage to those who love oils but are allergic to turps or mineral spirits. (Down side: the texture can seem stickier and tackier to those used to oils. Synthetic brushes are recommended for these paints as bristle brushes turn mop-like when used with water.)

My oil painting technique... A few Q's & A's

From time to time I will get questions from fellow artists about my approach to oil painting, so I thought I'd share some recent ones here on the blog, in case there are others who might have the same concerns: Q: How do you keep your colors clean painting in oil? Do you clean the brushes stroke after stroke? Do you wait for one coat to dry before applying a thicker one?    A: The best way to do this is to lay a stroke down and leave it be. I like to mix my paint on the palette with a palette knife in the studio, rather than mixing it around with my brush. When I paint en plein air, this isn't always the case, but starting out in oils I recommend it for keeping colors clean. Also, yes, clean your brushes often and wipe with paper towels. You need to have enough paint on the tip of your brush. Most beginners in oils don't do this and lay down a thin stroke, then see they didn't get the right effect and so try to paint over and over it a few times, giving a smeared, muddy effect. If you need to test the paint mixture to judge color notes or values, just dab a bit of paint on the canvas with your palette knive to test before laying on a bunch of paint.

You can paint either using a direct method or an indirect method. I paint using a direct method, where I am laying paint rather thickly on canvas, sometimes doing it all "alla prima" (at one go) for smaller canvases, or in consecutive sessions for larger canvases.  You can use a painting medium like Galkyd or Liquin, which speeds the drying and increases fluidity. There are also impasto mediums that help the paint sit up thickly and "stay put". But if you use these, use them sparingly or else it compromises the stability of the paint.

I saw Ken Backhaus and John Budicin demoing in oils recently and neither of them used any medium at all. They just laid the paint on pretty thickly and left it be.  It does take some practice to do this, though, and some confidence in handling your brushwork.   Indirect painting is approached differently, using glazes that build up through layering. With this method you WOULD let the painting dry to the touch in between sessions, painting thinly and gradually building up the paint layer. The rule here is to pain "fat over lean", meaning paint thick over thin, oily over less oily. Lots of portrait painters use this indirect method, which gives a beautiful luminous quality to  translucent passages such as skin.

Q: How do you keep your deep dark values clear cut separate from your light? That goes for structures as for skin tones. 

My dark passages and shadow areas are generally painted a bit thinner than highlighted areas. I leave the impasto (thick, raised paint) for highlights, which are naturally going to be more opaque because of the addition of white paint used in the mixtures.

The best way to keep your darks clean is to not move your paint around so much on your canvas once it's down. Think in terms of laying the paint down rather than smearing it around. Also, to keep darks dark, you can lay them in first and then lay in impasto highlights after. If you do it the other way around the light, which usually includes white will muddy and lighten the dark . If you do need to darken something, wait until the paint "sets up" a bit and becomes at least tacky to the touch before going back in with dark over light. If you've worked in watercolor before, this will be the exact opposite approach to watercolor!