Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of 3D Systems Corporation (DDD -0.86%) fell more than 10% early Tuesday, despite solid first-quarter results from the additive manufacturing specialist.

So what: Quarterly sales rose 45% year over year to $147.8 million -- including organic growth of 28% -- which translated to adjusted earnings of $0.15 per share. Analysts, on average, were expecting the same earnings of $0.15 per share, but on slightly lower revenue of $145.5 million.

The market was less enthused, however, about 3D Systems' full-year guidance. Despite the small top-line beat, 3D Systems chose to reiterate its previous targets, which call for revenue of $680 million-$720 million, with adjusted earnings per share in the range of $0.73-$0.85. The mid-point of both ranges sits slightly below analysts' expectations for 2014 revenue and earnings of $701 million and $0.81 per share, respectively.

Now what: It's obvious the market was hoping for a bigger beat and raise, but I think there was plenty to like about 3D Systems' report. For example, unit sales growth of design and manufacturing printers rose 76% over the same period last year, while consumer revenue climbed 150% to $9.7 million this quarter thanks to a strong showing from its Cube printer lineup. Meanwhile, 3D Systems says its March 2014 backlog included $17.9 million of printer orders, in part due to demand continuing to outstrip manufacturing capacity for its Direct Metal 3D printers.

Better yet, while 3D Systems' increased investments in sales, marketing, and R&D continue to pressure quarterly earnings, CEO Avi Reichental insisted they expect more attractive operating leverage to "resume in the second half of 2015 and be fully restored the following year."

With shares now down more than 50% year to date -- and keeping in mind I've long suggested 3D Systems' investment strategy is great to see as it shuffles for position in a burgeoning industry -- I think today's pullback is a perfect opportunity for patient, long-term investors to add to their positions.