Presbyopia is a condition in which the eyes are not able to focus on near objects.

Every 15 minutes or so, look up and focus on distant objects for about 2 minutes.

In middle age the lens of the eye becomes harder, and we may need glasses to focus on near objects.

Starting at about age 40, your eyes begin to lose the ability to focus on close objects (presbyopia).

Both these changes decrease your ability to focus, especially on near objects.

Depth of field is extremely small when focusing on close objects.

In some cases of hyperopia, the eye cannot focus on distant objects either.

The collection focuses on objects from c. 1860 to 1980.

It will focus on objects made before 1840 and the onset of mass production.

The eyes' lenses become less flexible and can't change shape to focus on objects at reading distance.