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 thermal imaging systems maker FLIR Systems (Nasdaq: FLIR) fell as much as 13% after the company announced preliminary second-quarter results.

So what: FLIR expects revenue of about $390 million and earnings per share of $0.18, or $0.35 after adjustments for one-time items in the second quarter. That fell short of expectations of $0.37 from analysts and brought a downgrade to market perform from outperform from Morgan Keegan analysts.

Now what: Weakness in the defense market is slowly taking its toll on suppliers, and FLIR is the latest to get hit. Shares aren't terribly expensive at 14.4 times forward P/E, but with defense spending likely to continue to come under pressure, I would be cautious buying here. Without any catalysts in the future, I would like to see if momentum continues downward in the next week before buying shares of FLIR.

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