Ron Tarver, Philadelphia. He's a staff photographer for the Phila Inquirer, but his personal work is 4x5, uses Type 55 Polaroid film and a printing technique which softens the image. He received a 2001 Pew Fellowship. He has some lovely pictures of Havana, and urban landscapes around Philadelphia.

I think Don Camp (also Philadelphia) uses LF for his huge portraits, but I'm not entirely sure.