The release also introduces enhanced imaging tools for highlight recovery, colour vibrancy, local contrast definition, soft-edged retouching, 'vignetting' and Raw fine-tuning.
Rob Schoeben, vice president of applications product marketing at Apple, said: "With its simpler interface and lower price, anyone can take full advantage of Aperture's power."
Interface improvements let users navigate between Viewer and Browser modes with a single key command.
Screen size is maximised for images with an all-in-one heads up display that allows users to toggle between library, metadata and adjustment controls in a single tabbed inspector.
The All Projects view, modelled after iPhoto Events, provides a poster photo for every project and the ability to skim through the photos inside.
The integrated iPhoto Browser offers direct access to all the events and images in the iPhoto library.
Apple claimed that performance has been enhanced in Aperture 2 to make it faster to import, browse and search large volumes of images.
Embedded previews let photographers caption, keyword and rate images as they are being imported, and continue working while images are processed to JPEG, TIFF, PNG and PSD file formats.
Aperture 2 is available immediately for a suggested retail price of US$199. Owners of previous versions can upgrade to Aperture 2 for US$99.