When a selection has been decided upon and framed to a good proportion, fasten the finder to the photograph and then on very thin tracing paper with a soft pencil make a simple tracing, not in outline alone but in values, trying to give the effect of the whole in a direct and simple manner, with sufficient accent at the center of interest. Do not spend more than five minutes on the sketch and then frame the same object in a slightly different way and make a second tracing. Compare the two. If one is better than the other, why? Is it because you have shown more foreground or sky, or because the frame has been kept of a size or shape better suited to the leading objects? Ask yourself such questions and then make perhaps a third and even a fourth sketch, comparing them all with care, and if one seems better than the others, make a larger and more carefully finished drawing using this last sketch as the basis of your composition. Next try to find some entirely different composition in the same photograph, using a new subject, and make another series of quick sketches or tracings, and again compare them and analyse each, trying always to learn by this comparison why one composition is good and another not. Select a different photograph and repeat the process, or, if you feel that you have the ability to work in a similar way from nature, do so, choosing a comparatively simple subject so that each sketch can be done in a few minutes.
One will encounter more difficulty when working from nature, for whereas on the photographs the forms and values remain constant, in nature the values are always changing and the forms more difficult to represent. We have previously had occasion to mention that subjects which are full of interest and good in composition during some hours are entirely different under changed lighting conditions, and buildings which appear to good advantage at certain times of day are much less pleasing at others. This is largely because the areas of shade and shadow are never the same for long. Part of the time they nicely balance one another so that the lights and darks are all well related. At other times too much light or too much dark appears at one side or above or below, thus destroying the restful effect. At some hours, too, there may be patches of shade or shadow so odd in shape as to prove distracting. It is therefore well to do your sketching during favorable moments, if this is possible, returning, if necessary, to the same subject at the same hour during a number of days in succession until the study is completed.
If a subject which is otherwise good in composition exhibits a few unpleasant features, either in nature or in the photograph, it is perfectly legitimate to take certain liberties with them, if by so doing the drawing can be improved without sacrificing the truth of the main idea. Should a tree, for example, seem a bit too small in relation to a building, or too light or dark in value, or should some shadow be too dense and black or form a displeasing mass, it is permissible to make such changes as seem necessary to improve the composition providing the final result represents a condition which might be possible under slightly different circumstances, without the breaking of any of nature's laws.
In landscape painting and decorative drawing more such liberties are taken, however, than are permissible in most architectural sketching or rendering, for architecture must as a rule be truthfully portrayed, the changes to better the composition being made for the most part in foliage, shadows, and the like. To illustrate this matter of changes, we have shown in Figure 25, Sketch 2, the dark boat in exactly the same position as on the photograph. This spacing is not wholly satisfactory as the boat seems isolated in the center of the sheet, attracting by its placement more than its proper share of attention. In such a case as this it would be better to improve the composition by moving the boat to the right or the left or it might be tied into the scheme by the addition of extra lines or tones. Amendments like this are always advisable, and it is also wise to omit from a sketch such objects as have little or no relation to the subject itself-, and which, for this reason, detract from the main idea which the drawing is intended to express. This means that we must observe the "Principle of Unity," which requires that a composition must be a homogeneous whole, all its parts related and so thoroughly merged and blended together that they become a single unit. In order to secure unity in a drawing only as much of the material before us is selected as relates directly to the subject of the sketch. Separate your subject from everything else that is visible, and think of it as a single harmonious whole. This rule applies whether your subject be an entire building, or some portion such as a dormer window or some still smaller detail, - a door knocker, for example. Once you have determined which of the ideas are to be rejected as irrelevant, you must decide on the relative importance of those which have been accepted as essential, for unity in a drawing depends not only on the selection or rejection of material but on its emphasis or subordination as well, for unless each detail is given just the amount of attention that is proportionate to its importance, the composition will not count as a complete and satisfactory unit. Failure to give sufficient emphasis or accent to the leading parts of a drawing causes a loss of force to the entire composition and in the same way neglect to properly subordinate the unimportant parts leads to confusion and complication.