Seeing is believing, they say, and seeing more clearly and faster when moving from indoors to bright sunlight (and from sunshine to inside) is even better.

That's what the new Transitions Gen 8 light-adaptive lenses do. Gen 8 lenses, which debuted in the US in July 2019, activate faster outdoors and the fade back once you're inside is quicker, too.

"Under normal conditions, we're talking about a 35-second activation," says Dr. Ryan Parker, OD, director of professional education at Essilor of America. Transitions Gen 8 Signature lenses "fade back indoors in less than five minutes."

It took three minutes longer for the previous Transitions generation of lenses to activate.

Of course, the speed that photochromic lenses adapt to bright or dark light depends on the light itself. If it's cloudy outdoors, instead of full sun, your fade back time when you get inside will be faster.

Transitions Gen 8 lenses also get darker than Transitions Signature 7 lenses, providing even better protection from the sun's harmful UV rays. Indoors, the Gen 8 lenses also filter blue light from computer screens, smartphones and other digital devices.

Transitions Gen 8 lenses, which are the result of five years of research and development, also are the longest-lasting of Transitions lenses. With earlier Transitions lenses, it took about two years before wearers noticed the transition from light to dark starting to slow down.

Parker says nearly 80 percent of people who come in to get eyeglasses have an interest in purchasing Transitions lenses, but often no one working at the optical shops suggest photochromic lenses. While others also make photochromic lenses, Parker says he's confident Transitions beats the competition.

"Gen 8 outperforms anything I've seen right now," Parker says. "Not all lenses that go dark are created equal."

2019 was a big year for Transitions. In April 2019, Johnson & Johnson Vision introduced Acuvue Oasys with Transitions, the first light-adaptive contact lenses.

As part of the Transitions Gen 8 launch, the Essilor Next Gen Offer is a spin on a buy one-get one promotion. People buying their first pair of Transitions Signature Gen 8 lenses can also get a second pair of clear lenses free. The free clear lenses include any Crizal , Varilux, Eyezen+ or Essilor Single Vision lenses with purchase of frame.

SEE RELATED: Photochromic vs. Transition Lenses