Late Summer Flower Pots - Day 2 + Thoughts on Alla Prima Vs. Multiple Layers + Adding Specific Palette Colors

  I've been thinking a lot recently about alla prima painting and its benefits, but also the benefits of working with multiple layers of paint.  I know that there's a huge advantage in being able to paint quickly; to be able to render a scene with speed is an absolute necessity when painting en plein air.  But this doesn't mean that I always finish a painting in one session.  Sometimes this is the case and I can finish a painting in one shot, but that is usually a function of the size of the canvas; I can usually complete a smaller painting in one or two sessions.  I can also usually get a nice sense of light in one session, but the level of detail and finish will be limited.  I think of it like how a writer can write a short work (like a poem or a short story) or a novel; there's a certain beauty with a poem, but there's a sense of power and the passage of time that comes with a novel. 
  The other factor in this is if I have the opportunity to return to a spot.  If I have one opportunity in a location and know that I won't return to a spot then I usually work more quickly and on a smaller scale canvas.
  So alla prima has a certain function, but there's a nice feeling that I find when I return to work on a painting.  If I can return to a painting and work more on it then that usually means the piece will have a higher level of detail and refinement.  Larger paintings simply need more time to complete and a certain level of finish can only be attained with multiple layers of paint.  There can also be confusion about if the paint gets dry and sunken in, but you can oil out the painting if it's totally dry.  Usually I don't even bother and I just start painting.
 If I'm going to return to work on a painting, I've found it helpful to make a note of my starting time and make sure the weather conditions are close so that I don't have to change too much.  Of course, there's always changes and you have to adjust, but that's part of the challenge and magic of working on plein air.
  A further note about color palettes: I like working with a fairly standard palette of 10 - 12 colors, but sometimes I find that I need to use a color to match something that I see in nature.  In this case, one of the flower pots has a specific green that I know I could get with a color called Veronese green (also sometimes called Emerald green); the color is a variation of Viridian and comes in handy once in a while.  I don't have this color on my standard palette, but I'm going to add it to my palette during my next session.
  Color palettes can be confusing and an area for navel gazing, but if you see that you need a color then USE IT.  Don't get locked into a specific palette or technique.  I recommend that all my students start off with a standard palette, but also experiment and gain a wide knowledge of as many colors as you can.  Knowledge is power.