“It cannot be too frequently pointed out to students of the period that both academicians and impressionists were justified in their respective aesthetic aims and that it is absurd to hold one type of painting to be a higher form than the other.
“...[T]hese objectives (of academic Lefevbre and the others) are alien to the impressionist endeavor which, as we have noted previously, aims to report the immediate impact of something seen and observed by the painter in its envelopment of light and atmosphere. Both ideals have suscitated great works of art, but each should be judged by its own criteria with the painter’s specific intent in mind .... a painter is obviously free to choose between these two mutually incompatible goals and his preference is usually determined by his native inclination.
“The word, 'impressionism' admirably suggests this purpose and differentiates it from a realism which seeks to imitate appearances rather than convey an artists reactions to those appearances...Indifferent to the world of the imagination they were deeply stirred by the world they saw about them.” R. H. Ives Gammell
The evidence clearly supports the idea that representational pictures are of two basic sorts: imaginative, or pictures first seen in the mind and then pieced together like fiction writing in literature, and impressionistic, or pictures of the world as seen before the artist at the moment; a kind of "journalism of the senses" (though such an analogy may not entirely suffice.) For the purposes of this discussion, since it revolves around the teachings of Gammell, it is the key differentiation.
Michelangelo's Sistine Ceiling, David's Oath of the Horatii, Leighton's Cymon and Iphigenia and most of the works of Gammell, are examples of the former. The creation of such works require many levels of preparation. The poses and groupings of the actors are drawn up as thumbnail sketches which are then most often worked up in detailed studies from live models. Clothing is studied in separate drawings, perhaps with the use of a manikin. Architecture is drawn out in some detail, often with three-dimensional models put to use. In Poussin's case, detailed dioramas were constructed which featured clay figures sculpted to scale. Elaborate layouts of all the elements are drawn onto paper, and traced or squared up onto the canvas or wall. Detailed grisaille studies of the parts and/or the whole are typically painted onto the surface before any color is added. The work proceeds in this complicated, indirect, and procedural vein ... ultimately leading to the final full color covering of paint for which many, if not all the parts, had been pre-painted as color studies. This form of the picture making craft is mechanically very complex, and has produced amazing results for those inclined to a work of the imagination. Creating a work in this way is a time consuming, and usually a very expensive proposition. The sort of work a wealthy government or church might have commissioned or promote in its institutions of art, but which a poor or middle income painter would have been hard pressed to endeavor. The Prix de Rome and a chance to study with masters of such painting in Rome was awarded by the government of France in specially designed competitions to young men who proved adept in its production.
The word 'impressionism' was put to use by Gammell as the label for any paintings done from nature essentially just as the artist sees it before them, or as a reasonably proximal interpretation of what they see. Yet Monet and others of his plein air landscape painting circle were those first associated with the appellation. Speaking to the term's use as a descriptive for work done directly from life, R. A. M. Stevenson considers it understandable that “...[I]mpressionism was first fully made manifest in the work of a portrait painter.” Specifically Velasquez, (for whom his book is named and his inquiry prompted.) Still-lifes and interiors - like those of Chardin, Vermeer, or Velasquez - were initially set up, then painted on the spot as wholly pre-designed subjects. As their subjects stood before them as a gestalt, their process of execution was more direct and far more efficient than those of the imaginative painter. To paint a still-life, the impressionist will select and arrange the objects, select a lighting and vantage-point, decide the picture's size and proportions, stretch a canvas, and simply go to work. With figurative subjects, the model will be placed in a pre-arranged setting and assigned a pose which they will hold like a potato on a plate for as long as needed. The human model may be absent from the setting while the artist works on other elements, but ideally the ensemble is always together and apiece.
The outdoor landscape is even less complicated, with the artist doing very little arranging - little more than looking around, finding a scene through their viewfinder, and setting canvas on easel. The only preliminary may be a small thumbnail drawing or a color study for initial review. From that point forward and without further ado, the impressionist directly renders what they sees before them with as much grace and efficiency as possible.
Less direct methods may be used by some impressionists who will enact preliminary drawings of the scene or set-tup before them. The Gammell method for students included full value preliminary drawings of the whole, to be sized up and traced onto canvas, which is then laid in and subsequently finished one area at a time. This outline based method differs decidedly from that of the Boston School referred to by Gammell as the greatest evolution of impressionism. It is more closely tied to an older way, similar to that involved in producing Velasquez' early bodegónes; ways ultimately dropped by him in his quest for a more vivid expression of the visual effect, ways more commonly used by the imaginative painter.
One final version of painting that would have to be considered 'impressionism' under Gammell's definition is the trompe l'oeil painting. It is treated historically as a deformity or a curiosity by comparison with the rest of impressionism, owing to its intentional exaggeration of detail and a tendency to reward a localized "looking in," rather than emphasize the truth of the larger impression. Having had to figure most things out for themselves, thanks to our widespread disconnect from the wisdom of the past, many of today's representational painters use curious combinations of any number of ways of handling visual truth even when working, as it were, "impressionistically."
The fact that impressionist painting could be fairly readily undertaken by those without much financial support contributed to an increase in the number of those aspiring to be painters in the first place. A major onslaught of truly bad painting naturally accompanied this trend, as fewer and fewer acquired even a modicum of the necessary underlying skills. The destruction of the drawing base in our educational institutions, along with the failure of individual artists with skill to personally take responsibility for the success of the next generation are equally to blame in the damage done to representational art in the last hundred years. These realities in no way diminish the brilliance of impressionism's “greatest practitioners” in the Boston School, especially given the notion, as affirmed by Joseph Decamp, that it is the method “easiest to understand but hardest to do.”
Although imaginative artists have found that a key to their strength is in the ability to create a visually plausible scene, neither their operation nor their results would be usefully labeled impressionistic. They are not simply responding to the seen world as it is, but creating one of their own out of whole cloth. And although in that effort an understanding of perspective and chiaroscuro, the anatomies of plants, animals and people, interior and exterior architecture and even how they relate in the settings are very helpful to them, the impressionist painter finds thinking of these things can be an actual hindrance to their success; success which is significantly measured by truth to the look of nature. At best this kind of knowledge is primarily (and ought to be used as) a resource for checking one's work.
Apart from accuracy of shape making and form interpretation, some compositional universals and, of course, skill in the oil medium, little of the complex technical craft of the imaginative painter is of use to the impressionist. It is inevitably piecemeal and object-based and would, if used by an impressionist, impair the hallmark unity of the visual whole. On the other hand, there is no question that the training undergone by the student of impressionism to see and accurately render the world before themselves visually would clearly benefit the imaginative painter in their quest for visual plausibility. All painters of stature speaking on the subject emphasize, before and all other considerations, the central importance of the mastery of the look of nature: key to understanding “la source” of art.