What sensory perception is relatively poor in fancy mice compared to their olfactory sense?

Their eyesight, which is near-sighted and renders them essentially colorblind.

Fancy mice possess an interesting dichotomy in their sensory capabilities. Their sense of smell, or olfactory sense, is described as extremely refined, which is vital for essential activities like communication, resource location, and navigating via scent marking within their environment. However, their visual perception is significantly limited. They are characterized as being near-sighted, meaning objects at a distance appear blurry. Furthermore, they are considered colorblind, indicating that the complex spectrum of colors visible to humans is not perceived by them. This poor vision necessitates a heavier reliance on their highly developed hearing and refined sense of smell to interpret and interact with their surroundings successfully.