Bleaching your teeth is both expensive and likely not a healthy solution for having white teeth in photos. Color correction is a much more cost effective solution and it works on everyone with no trips to the dentist. There are ways to achieve white teeth in Photoshop through a combination of built-in tools, but I find it much faster to use a plugin built specifically for the task of making teeth white. Enter PearlyWhites from Image Trends. Install the plugin for use with Photoshop, Paint Shop Pro, or any other app that supports the Photoshop plugin method and you'll get great looking teeth in every photo. Support for one off fixes or batch fixing of all teeth in a series of photos is supported. [Windows 9x/2k/XP $49.95]
Buy PearlyWhites with the coupon code mediablab and save 10%.
