LONDON — The target sits 70 meters away, three-quarters of the length of a football field. Ten concentric circles telescope from white to black to blue to red to gold in a bull’s-eye the size of a grapefruit. For Im Dong-hyun of South Korea, considered by many the world’s greatest archer, the colors appear blurry. He described them Saturday as paint dropped in water.

Im gave his vision as 20 percent of normal in one eye and 30 percent in the other. He said through an interpreter that at 26 he has the eyes “of an old man.” Yet he also said that articles depicting him as legally blind were inaccurate. If that were true, Im said, he would compete in the Paralympics, not the Olympics. Im called himself farsighted but said that he wore glasses to read only when tired and that he could drive without wearing glasses.

A South Korean reporter who knows Im well said that Im sometimes could not recognize him when they passed each other and that Im might be reluctant to be appear disabled or inferior for cultural reasons. It is impossible to know without speaking to his doctor the extent to which Im’s vision is impaired.

Although poor eyesight might be a disqualifying hindrance in many sports, visual acuity in archery is considered less important than an ability to shoot with consistent and repeatable technique, to remain calm under pressure and to judge the wind. Some experts believe reduced vision may even be an advantage, or at least not a disadvantage.