…we might now formulate a maxim to the effect that art -- that is, in our case, pictorial representation --- employs the image of concrete things to … - Alfred Horsley Hinton

Hence SELECTION in photography, or at least in landscape and some other branches of work, often takes the place of what in painting becomes voluntary COMPOSITION.

The chief characteristic of the pin-hole photograph is that we get a general suppression of focus in all parts the picture is nowhere quite sharp.

Probably every portrait photographer resorts to some such "dodge" for making a face lighter or other similar purpose, and he finds that the application of water-color paint in ever so thin a wash makes so much difference to the printing density that blue is commonly used as being a quick printing color, the effect of which is therefore not so great; an equally dense layer of blue and of red to any portion of a negative would print very differently, the red shutting off the light action much more powerfully than the blue.