As I sit here typing, I can see above the computer screen, through the window, across the quad, in the eucalyptus trees, a shiny purple, silver and gold balloon, torn and caught in the branches. It's been there for quite a while. The day I got my new glasses, I put them on so I could see how much clearer it would look from here. I was surprised that although the image became much sharper, the brightness and prominence of the colors were very much muted.
I like my glasses because, with them, I can read signs that are far away, and I can see leaf shapes, bark texture, birds, and animals more clearly from a distance. But in some ways, the world is more beautiful with the vertical axis out of focus.* Wrinkles, pores, and tiny hairs on people's faces are smoothed away. Colors are more striking. The whole world looks softer, friendlier. It's like living in a Monet.
In what sense do the glasses improve my vision? I can see the details better, but the larger picture becomes less clear. Is a photograph or a painting a more accurate representation of an object? From a scientific perspective a photo may be better--but from the perspective of human experience, from the point of view of one who does not merely see, but who attends, who looks with intention, who evaluates, appreciates, and longs for beauty, a representation that omits the details but brings out what is most important--the glory of purple and gold, shining among dusty green leaves--may be more true to the object than photographic realism.
*Vertical axis out of focus: I use this phrasing because astigmatism does not actually cause a general blurring of vision (it is not like unfocusing the lens of a camera)--it's more similar to seeing double.