“A few notes on the “focus” of the various pictures will perhaps interest the student, as this is just now a vexed question…. “Where winds the Dike,” this is another plate the student wishing to understand Naturalistic Photography should study carefully. The whole picture here is out of focus, deliberately thrown out of focus, and by the judicious use of diaphragms the middle distance and distance are relatively truly rendered. No lens yet made could give this effect by spherical aberration to be introduced by unscrewing back, etc. Dallmeyer’s valuable new rectilinear landscape lens, certainly could not give this effect by focussing sharply and the spherical aberration introduced in its manufacture being, trusted to give it.” ⎯ P.H. Emerson, Sept., 1889, To The Student