… to put it into slightly different form, it is not the facts in nature that the good picture aims at portraying, but the effects of light and shade … - Alfred Horsley Hinton

It is the subjects which might be imitated by pieces of paper of varying depth of color laid one over the other, which are the subjects that will give more readily the greater satisfaction.

As a general rule, therefore, the lights and shadows of clouds near the horizon are less vivid than in clouds higher up. Exceptions to this rough rule will be found when the source of light is near the horizon, as in sunset and sunrise, also when there is a gathering of local stormclouds which may hover over the distance as a dark pall, when there is fair weather and light, transparent clouds near to us.

But the quality of the result obtained by using a pin-hole to which its advocates attach most importance is the suppression of sharp focus over the whole image, no one plane being more sharply focused than another.