Turning points are powerful lenses through which students need to view our past. (gse.harvard.edu)
Chris McCaw builds his own large - format cameras and outfits them with powerful lenses typically used for military surveillance and aerial reconnaissance. (museemagazine.com)
Larger binoculars usually have more powerful lenses, but smaller binoculars are great for being carried in backpacks and pockets. (geekwrapped.com)