PHILADELPHIA (CBS) - More than 20,000 of the people who light up your life — literally — are in Philadelphia this week for a huge convention.

(Song plays: “You Light Up My Life…”)

“Lightfair is the largest architectural, commercial lighting show in the world,” says Helen Diemer (above), president of The Lighting Practice, a lighting design company in Philadelphia.  “The show always rotates between New York and Las Vegas, and this is the first time that it’s going to be in Philadelphia.”

Why did the show come here?

“Kind of an accident,” she admits.  “This year it would have normally rotated to New York, to the Javitz Center, but the Javitz Center is going through a renovation and wasn’t finished in time.”

Hear Lauren Lipton’s full interview with Helen Diemer in this CBS Philly podcast…

You may not know The Lighting Practice by name but you definitely know its work.

“We did the lighting for Philadelphia City Hall, for the Avenue of the Arts, for many of the buildings and monuments on the Ben Franklin Parkway,” Diemer tells KYW Newsradio.

She says lighting makes a city memorable.

“Probably the images you remember are the buildings that are lit, like One Liberty Place, the Philadelphia Museum of Art, Boathouse Row, the bridges, things like that. They have a magical quality to them that make them memorable.”

And Diemer says her industry is looking ahead to the future:

“A lot of discussions about light bulbs and what’s the right sources, and what lights are going to stay on the market.  Right now, there is a lot of emerging technology in LEDs.”

That’s Positively Philadelphia!

Reported by Lauren Lipton, KYW Newsradio 1060

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