The PGA Tour's stars are out in Los Angeles this week for the Northern Trust Open, and so are the Titleists.

 Ninety-four players in the field at Riviera are teeing up Titleist Pro V1 and Pro V1x golf balls, more than five times the nearest competitor with 17 and more than all other golf balls combined. Titleist was also first in iron sets (T-42); sand, lob and approach wedges (125); and putters (63).

Photographer Greg Moore, a loyal Team Titleist member, was out on the Riviera range earlier this week and sent along some pics to share. Check them out in the slideshow below.

Quick trivia question: After Sunday, the PGA Tour won't return to California for about four months. When will they be back? (Answer below the slideshow.)

(Answer: U.S. Open week, at The Olympic Club in San Francisco.)