Weird effect on Facebook widget and Google Ads

Hi,

I am currently using Fancybox on this link: http://mikabatchelor.com/nggallery/page-34/album-16/gallery-16/
and when I am using Mozilla Firefox, there is a weird effect on the
image when a part of it is on top of the Facebook widget and Google ads. I
tried to catch it so I can give you a screenshot, here’s what I got:
http://i50.tinypic.com/2vmec2c.jpg Again, it only happens when using
Firefox and on top of the ads and Facebook widget. I’ve tried it on
other browsers, everything’s running smoothly. Do I need to change
anything on the ads and Facebook widget? If yes, please let me know.
This is really important to me because most of my members are using
Mozilla Firefox.