Quick study vs. sustained study:  This is the other successful plein air quick study that I felt had merit.  Working for just a few hours and not laboring on details.  Again, the idea of a plein air study is to quickly surmise the landscape elements throught the gesture, capture a sense of light and form, work through the composition trying different configurations and then walk away from it.  Leave it alone.  I sometimes have a very hard time doing this and the energy of the mark and the freshness of the paint become labored and the whole idea of a quick study is lost.  That is not to say that one can not work on a painting on consecutive days of the same weather condition and continually pull out other elements and refine the work.  I also do this kind of painting but the "quick study" should be just that.