Light – both natural and artificial – breaks down any organic material. Damage is cumulative (and irreversible) with long-term exposure at low levels equal to short-term exposure at high levels. Considering many antiques have already undergone decades of poor lighting conditions, limiting future exposure is pertinent to longevity.
Limiting Exposure of Three Light Types
Ultraviolet (UV) light: The most energetic and destructive to antiques. Instead of enhancing view of objects, UV light only harms.
Purchase UV light filters: Filtered glass or plastic sheeting designed to limit UV exposure can be placed at windows, lamps, or arranged around the object.
Paint surfaces: Painted surfaces – especially in white - absorb much UV light with the added benefit of creating reflections that illuminate glossy or difficult-to-light objects.
Use incandescent lights: Incandescent lighting emits the lowest UV rays (halogen and fluorescents emit much higher amounts and natural sunlight contains the most). Ideally, sensitive objects should be under incandescent lighting with UV filters and no exposure to sunlight.
Infrared Light: Infrared, while less damaging than UV, causes heat to build, leading to deterioration. Sunlight has the highest amount of infrared, incandescent contains less, and fluorescent contains the least.
When possible, avoid direct sunlight and ensure artificial lighting is placed at sufficient distance from objects.
Avoid lighting units that attach directly to the frames of paintings.
Avoid containing light within enclosed spaces, such as display cases (this also prevents dryness).
Visible Light: Sunlight and full-spectrum florescent lights are more damaging than incandescent, UV filtered lighting. Though sometimes unavoidable, overall exposure can be reduced.
Ensure sensitive pieces and finishes receive as little direct light as possible: Hardy material like ceramic, metal, or stone will survive better than oil paintings and wood. Paper, textile, baskets, and wax are most susceptible.
Monitor light exposure throughout the day and as seasons shift: You may notice areas that only receive direct sunlight for short periods per day, merely requiring closed blinds or drapes during certain hours.
When possible, use reflected or diffused light as part of your lighting design or placement.
Rotate antique objects
Identical sets, like chairs, can be moved in differing positions or combinations. Objects without specific front or back sides can rotate, mediating exposure. Inevitably, antiques will be changed by light exposure. Spread that exposure across varying pieces in your collection, as well as across different surfaces on individual objects.