Hello, I own a Nikon D80 with an 18-200mm lens and a 50mm 1.4 lens. I'm taking photos of the dancefloor for prom this Saturday. Essentially, its nightclub photography. So I'm wondering if buying a Nikon 20mm 2.8 lens would be a good idea. I either buy something for under 1000 dollars, or I stick with my 50mm lens which may not be wide enough for group photos.