3D Systems' (NYSE:DDD) second-quarter earnings results may have disappointed investors focused on the bottom line, but the results were certainly encouraging for the long-term investor. In the video below, Fool.com contributor Steve Heller examines the negativity surrounding the report and explains why it's actually a great thing for the company's future prospects. He argues that if you're a long-term investor looking to get involved in the 3-D printing space, then 3D Systems may make a great addition to your portfolio.