The table shows what happens to the image as an object is brought from infinity toward a convex lens.
| Object Position | Image Position | Image Characteristics |
|---|---|---|
| At infinity | At focal point | Image is a point |
| Moving toward 2F | Moving from F toward 2F | Increasing in size, real, inverted, smaller than object |
| At 2F | At 2F | Real, inverted, same size as object |
| Moving from 2F toward F | Moving from 2F toward infinity | Real, inverted, larger than the object |
| At F | At infinity | Infinitely big |
| Moving from F toward lens | Moving from -infinity toward lens | Decreasing in size, virtual, upright, larger than the object |
As long as the image as real the ray diagram is reversible. An object at point A creates an image at point B, while an object at point B creates an image at point A.