A single version that is being adjusted and is displayed in the Preview panel. If multiple versions are selected and visible in the Preview panel, then the active version will be the last one added. Simply click on any of the other previews to select that version and make it active.

Adjustment tools in the Tools panel show the settings for the active version only.

Keywords are the exception in the Tools panel — they can be applied to all selected versions, not just the active version.

A catalog is a collection of photos and their associated image data. In essence, a catalog is a database that can be managed within Corel AfterShot Pro. Catalogs contain master files, thumbnails and preview images, image settings, image adjustments, and catalog-specific preferences.

The Corel AfterShot Pro Library is where you store and access your catalogs.

A master file is a photo that you have opened in Corel AfterShot Pro. The master file is treated like a photo negative — it is protected from any direct changes. Master files can be RAW files, JPEG, or TIFF. All master files are edited and managed non-destructively.

A master version is the preview generated for the master file in Corel AfterShot Pro. It is an editable preview that corresponds to master file (protected) + edits (saved to XMP file and possibly a catalog file). If you delete/remove a master version in Corel AfterShot Pro, the master file and all related versions are moved to the Recycle Bin.

A group of images that are similar in content or subject matter that can be "rolled up" to show a single image representing the whole group, or "expanded" to show all the images in the stack.

When making image adjustments in Corel AfterShot Pro, you are editing versions instead of altering the master file. The initial thumbnail is called the master version. You can have many versions from the same master file; for example a color, sepia, and Black & White version — all based on the same master file.

Luma or Luminosity is a measure of the brightness of an image or pixel. This is typically calculated as a 0.2126 R + 0.7152 G + 0.0722 B. Luma is also called Value in the HSV (Hue Saturation Value) color model.

A measure of the color of an image or a pixel, sometimes called Hue, as in the HSV color model.

Asset management involves importing your photos to create photo databases (called catalogs) that manage the data related to your photos. The databases make it easy find and track your photos based on photo data, such as EXIF info or ratings and keywords that you assign. Asset management also involves archival tasks, such as creating backups or exporting databases.

Metadata, in a photographic context, refers to all the information related to a photo. It can include data that comes from your camera settings, such as shutter speed, aperture, and ISO. It also includes EXIF data, such as time and date the photo was taken. You can also add metadata, such as keywords, ratings, and captions.

JPEG (Joint Photographic Experts Group) is the most widely used digital image file format, ideal for sharing photographs on the web, in email, or as final-product images. JPEG files are compressed using Lossy Compression, and thus do not contain as much data as RAW or other lossless file formats.

TIFF (Tagged Image File Format) is a file format for digital images that provide the highest quality output image from Corel AfterShot Pro. TIFF is a broadly supported file format that saves all the detail and color information in your photographs without using lossy compression (unlike JPEG images). TIFF images are quite a bit larger in file size than a comparable JPEG image.

Often called "digital negatives", RAW files are digital photo files that capture relatively unprocessed (thus "raw") data from the digital camera's sensor. The files tend to be larger than other file formats because they capture a wide range of image data. The data gives you more precise image adjustment results and more post-processing options. After you adjust the files, they must be "developed" by outputting them to a standard file format, such as JPEG. Different camera models produce different RAW files formats (for example, many Canon cameras produce CR2 files and most Nikon cameras produce NEF files).

A workflow, in the context of digital photography, refers to the process that occurs between the time you capture a digital photo and the time you output the photo to its final destination and format. This includes everything from getting your images off your camera and into your computer, adding keywords and other metadata, editing and optimizing your images, managing backups and archives, printing, outputting to the Web, as well as many other steps and processes.

An industry-standard set of metadata used to label and categorize digital photos. It was created by the International Press Telecommunications Council and used by many photographic agencies and applications.

This is a newer standard that includes many improvements.

A sidecar file is any file that is associated with an image file and is found in the same folder as the image file. These typically include:

The technology and processes to match color across multiple image capture and reproduction devices. Proper color management ensures that colors are rendered on screen and in prints as faithfully as the various output technologies allow.