FL-DAY is for use with daylight type
fluorescent lamps. It is recommended that auxiliary light sources be used when
long exposures become necessary due to insufficient light.
Florescent lighting has characteristics that affect color rendition. This color
shift is not usually visual to the human eye but will cause adverse effects on
When shooting under "daylight" florescents your pictures will have a purplish
tone. Hoya's FL-D filter corrects and restores a normal color balance.
In industrial situations you might encounter "warm white" florescents which will
give a greenish tone, requiring Hoya's FL-W corrective filter.
Both filters are available in coated and multi coated (stronger flare
prevention) versions and all popular sizes.