sentences:  DSLRs became affordable around the mid-1990s, and have become extremely popular in recent years.Some manufacturers, for example Minolta, Canon and Nikon, chose to make their DSLRs 100% compatible with their existing SLR lenses in the beginning, allowing owners of new DSLRs to continue to use their existing lenses and get a longer lifespan from their investment.Others, for example Olympus, chose to create a completely new lens mount and series of lenses for their DSLRs.