From Cinematography.com...

Today on the set of "Big Love" word came down that Jim Glennon, ASC, who also shot Season One, died this morning in a hospital. I [David Mullen] was supposed to alternate episodes with him, but had to finish the last day of his first episode after he fell ill, and also shot Episode Three after completing Episode Two (Haskell Wexler just completed Episode Four after Jim asked him to come in.)

I spent much of Episode One watching him work and talking to him to get a feel for the look of the show. He was a generous and energetic individual, a very passionate soul who loved to teach others what he had learned. Much of the cast, production office, and crew, who had worked with him last season as well, plus other HBO shows like "Deadwood", were quite devastated by the news.

Jim is probably most known for the Alexander Payne movies he shot (like "Election") and for being the U.S. locations Director of Photography on "Return of the Jedi" working alongside DP Alan Hume.

Jim's credits:
http://www.imdb.com/name/nm0322694/

Jim's father was Burt Glennon, ASC:
http://www.imdb.com/name/nm0322688/