Filter Forge 3.0 offers a better way to preview effect filters. The functionality of the ‘Show Original’ checkbox above the preview area has been expanded: when you turn ‘Show Original’ on, Filter Forge 3.0 displays both original and modified images side-by-side and allows you to drag the before/after separator to better see how filters affect various parts of the image:

Filter Forge's amazing node based editor has been invaluable in giving us the power to create textures that make the most of today's real-time pixel shaders.
Karl Wickens
Visual Effects Lead Artist
Electronic Arts
www.ea.com
Filter Forge is an excellent filter creation tool with a strong community spirit that will enhance your Photoshop creations.”
Nick Mead
Reviewer
en.softonic.com
“I do think you guys are likely the best software company I've ever had dealings with.”
Ian Davis
Digital Artist
www.ionclad.com/