Q: I have some Transition (photochromic) lenses and sometimes only part of a lens will get dark in the sunlight. Why would this happen? When I get them checked out they always seem to work properly.

A: Beware of how your lenses are shaded from the sunlight. For example, wearing a brimmed cap outdoors can produce uneven illuminance on the lenses, which will make the lenses unevenly dark. If you like wearing ball caps, these lenses might not suit you well. These versatile lenses are often very comfortable to wear, so consider a larger brim or no hat at all when you’re wearing them. If you need advice about purchasing lenses, come see us at Mosaic Optometry!