TUCSON, Ariz. — Investigators revealed that Jared Loughner appeared to pull a frantic all-nighter last week to prepare for the shooting that killed six people, including a federal judge.

The judge, John Roll, was honored Friday at an emotional funeral Mass.

The night before the rampage, authorities say, Loughner, 22, dropped off at a drugstore a roll of 35-millimeter film containing images he had shot of himself posing with a Glock semiautomatic pistol. The authorities said he picked up the film early on the day of the shooting at a Walgreens in the same strip mall where he would later open fire at a citizens’ forum held by Rep. Gabrielle Giffords, D-Ariz.

According to the timeline the police have constructed of his movements, Loughner checked into a Motel 6 after midnight last Saturday. He returned to Walgreens to pick up the photos and make another purchase at 2:19 a.m. At 4:12 a.m., he posted a bulletin on his MySpace account titled “Goodbye friends” that contained one of the photographs on the roll of film — an image of the gun, investigators said.

Just after 6 a.m. he made another purchase at Walmart and at a Circle K convenience store. At 7:27 a.m. he bought bullets and a black diaper bag at a Walmart.

Shortly after that, he was stopped by an officer for running a red light. He returned home, where his father confronted him about what was in the diaper bag.

He fled on foot and went to the Circle K, where a cab picked him up and took him to a Safeway supermarket. Sixteen minutes elapsed between the time he entered the Safeway and when he began shooting just outside the entrance.

The shooting injured 13, not 14, as was originally reported, a decrease a sheriff’s spokesman attributed Friday to the initial confusion surrounding the attack.

The suspected target of Loughner’s attack, Giffords, continued Friday to make significant medical progress, her doctors said.

At the funeral for Roll, colleagues spoke about how his death had left a gaping hole in Tucson’s legal community. His absence has also created a huge backlog of cases, prompting federal judges from across the country to offer to help with his workload, colleagues said.