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PercepTool 3™ is a Photoshop plugin that performs Perceptual Effect and Tone Mapping operations on digital photographs. In this new version we have included some new functions: Disc Blur™, Film USM™, Re-Interpolate™, History Snapshot™ and Sharpen Snapshot™. It is compatible with both Windows and Macintosh platforms and covers CS5-CC versions of Photoshop. PercepTool 3™ works with both B&W and Color images in 8 bits and 16 bits, and some operations are covered with Photoshop Extended version in 32 bits. This new version is completely revised and updated.

Perceptual Spectrum™ is a redesigned version of the old PercepTool™ 2. Highlights and shadows are now protected. Equalizer™, now a perennial favorite among PercepTool practitioners, is updated and is a superior tone mapping interface. LiveView™, the ability to work on an image itself and not a preview, is unique to this software. Disc Blur™ mimics the lens of the eye rather than a Gaussian Blur used often in Photoshop. Film USM™ duplicates the old darkroom Unsharp Mask, and produces a better result than Photoshop’s Unsharp Mask. Re-Interpolate™ adds an accurate sense of detail to enlarged image files. History Snapshot™ performs a History Palette snapshot and returns the file to it’s previous state. Sharpen Snapshot™ provides a special sharpening state for George DeWolfe’s Local Edge Control Workflow™.

Perceptual Spectrum™ takes the image made in the digital camera sensor (or a scanned image) and changes it into what the brain actually perceives. This image, called the Luminance Image, consists of 2 sub (intrinsic) images: reflection and illumination. The reflection and illumination images are separated from the luminance image by the human visual process and recombined into what is known as the percept, or the image that we actually perceive. We call this luminosity. Most of the changes are due to differential combination of the edges and optimized tonal values.

Most of the other plugins in PercepTool 3™ have to deal with George DeWolfe’s Local Edge Control Workflow™. Even though Perceptual Spectrum™ takes care of the global processing of what the visual image should look like, local control is necessary to bing out the full substance of a photograph and create presence. The technique is based on local edge techniques I learned from James Bama, the famous illustrator.

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