Micro Four Thirds system functions.) For the Four Third lenses that can be mounted on MFT bodies, see Four Thirds system lenses. For the Four Third lenses that support AF, see the Olympus website. For those that support fast AF (Imager AF), see the Olympus website. Wide zoom lenses Standard zoom lenses Telephoto zoom lenses Superzoom lenses On Jan 9, 2012 Sigma announced its first two lenses for Micro Four Thirds, the "30mm 2.8 EX DN and the 19mm 2.8 EX DN lenses in Micro Four Thirds mounts". In a press release posted on January 26, 2012, Olympus and Panasonic jointly announced that "ASTRODESIGN,
Rule of thirds (diving) Rule of thirds (diving) In scuba diving, the rule of thirds is a rule of thumb used by divers to plan dives so they have enough breathing gas remaining in their diving cylinder at the end of the dive to be able to complete the dive safely. This rule generally only applies to diving in overhead environments, such as caves and wrecks, where a direct ascent to the surface is impossible and the divers must return the way they came. For divers following the rule, one third of the gas supply is planned for the outward journey, one third is