GoPro investors and users seem to share a thrill-seeking attitude. Image source: GoPro.

What's happening: Shares of GoPro (NASDAQ:GPRO) fell as much as 10% on Tuesday. The stock recovered somewhat before the closing bell, ending the day 8.7% lower. The move was not triggered by any particular news.

Why it's happening: The maker of high-definition digital cameras had no news to share today. Colin Born, GoPro's vice president of investor relations, took the stage at an industry conference, but reportedly did not share anything profoundly significant at that event. Anyhow, GoPro's deepest drop fell before that presentation started.

The camera industry wasn't bubbling with relevant information, either. Other camera-heavy consumer electronics companies saw their stocks stay within a couple percent of breakeven today -- some up, some down.

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.

Chip designer Ambarella, which provides video processing semiconductors for GoPro's cameras, also fell 4.5% on Tuesday, moving mostly in lockstep with its largest customer. But Ambarella's news flow ran dry, too -- this was a simple case of the stocks automatically moving together, like they normally do. This makes sense, since their businesses are so closely linked together.

So this was just another day in the life of an extremely volatile stock. GoPro shares have swung between $37.13 and $98.47 over the last 52 weeks, or a 165% difference between prices at the top and the bottom. Moreover, 13% of GoPro's shares are currently sold short, setting the shares up for additional swings when these negative bets are adjusted, abandoned, or increased.

The drop brought GoPro shares back to prices last seen in mid-July. The stock has still gained 57% during the last 52 weeks, and GoPro trades at a lofty 50 times trailing earnings today.