...strictly speaking, tone is the relative lightness and darkness due to the effect of light governed by atmosphere, and has nothing to do with the r… - Alfred Horsley Hinton

...he (a photographer) forgets that unless he has learnt when the tones of a picture are right or not, he will not know whether his work is good or bad, nor know what to try and overcome in future.

It must not be supposed that it is always necessary to present our landscapes with an attractive and well-defined arrangement of clouds; on the contrary, it will often happen that the effect of a scene is best emphasized by a mere grey tint representing a covered sky or even a blue, cloudless sky; but this is a very different thing to rendering it as a white blank.

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.