[Help Wordpress] Slider do not display correctly until I resize browser window

I think I'm doing everything correctly, but my sliders do not load in the correct size. The image displays very small. But when I resize the browser window, even just a tiny bit, the slider corrects itself and looks good. Here is an example:
http://2013.riverrockcreative.com/2013/wet-dry-try-from-slate-to-ta...
Any ideas?

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