Ozzy Osbourne of Black Sabbath performs aLollapalooza on opening day in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Kevin O'Neill of Bolingbrook has his Haley Reinhart CD signed during Lollapalooza in Grant Park on Friday.

Joel Bissell | Staff Photographer

Lollapalooza fans head through the gates.

Joel Bissell | Staff Photographer

Haley Reinhart performs during Lollapalooza in Grant Park on Friday at the BMI stage.

Joel Bissell | Staff Photographer

Haley Reinhart performs during Lollapalooza in Grant Park on Friday at the BMI stage.

Joel Bissell | Staff Photographer

Haley Reinhart performs during Lollapalooza in Grant Park on Friday at the BMI stage.

Joel Bissell | Staff Photographer

Haley Reinhart performs during Lollapalooza in Grant Park on Friday at the BMI stage.

Joel Bissell | Staff Photographer

Haley Reinhart performs during Lollapalooza in Grant Park on Friday at the BMI stage.

Joel Bissell | Staff Photographer

Haley Reinhart performs during Lollapalooza in Grant Park on Friday at the BMI stage.

Joel Bissell | Staff Photographer

Haley Reinhart signs a t-shirt .

Joel Bissell | Staff Photographer

Die Antwoord's Ninja, Watkin Tudor Jones, from the South African rap group performs at LollaPalooza on Friday night.

Joel Bissell | Staff Photographer

A fan waves a City of Chicago flag.

Joel Bissell | Staff Photographer

Die Antwoord's Yo-Landi Vi$$er, from the South African rap group, performs at LollaPalooza on Friday night.

Joel Bissell | Staff Photographer

Die Antwoord's Ninja, Watkin Tudor Jones, from the South African rap group, performs at LollaPalooza on Friday night.

Joel Bissell | Staff Photographer

Klara Soderberg of the Swedish group First Aid Kit performs Friday at Lollapalooza.

Joel Bissell | Staff Photographer

Fans dance their way between stages at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Fans gather for a performance by Yellow Ostrich XX at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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rtists put the finishing touches on the Perry's Stage sign at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Fans dance their way between stages at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Alex Schaaf from Yellow Ostrich performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Music fans enter the Lollapalooza music festival in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Ozzy Osbourne of Black Sabbath performs aLollapalooza on opening day in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Chicago Mayor Rahm Emanuel takes the stage to introduce the Black Keys (unseen) on Friday, Aug. 3, 2012.

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James Mercer from The Shins performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Jessica Dobson from The Shins performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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James Mercer, left, and Richard Swift from The Shins performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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James Mercer from The Shins performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Members of the crowd dance at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Yolandi Vi$$er from Die Antwoord performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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A man reaches to fill up his water bottle from a spray mist fan at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Dan Auerbach from The Black Keys performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Yolandi Vi$$er from Die Antwoord performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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James Mercer from The Shins performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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Dan Auerbach from The Black Keys performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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A couple shares a private moment at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012.

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