How much protection do brown bottles provide against skunked beer?

General Homebrew Discussion
1

Nowhere have I ever found any info on the degree of protection brown glass bottles provide against light-struck beer.  Is it limited to a few hours in the sun or bright lights, a few days, or is it absolute?

Thanks in advance for your answers.

2

From Basic Brewing way back when: http://www.edenfoods.com/articles/view.php?articles_id=181

3

Thanks!  A lot of good info there.