Selection

A way of separating out a specific part of a picture for adjustments. Selections can be made using a variety of tools such as a rectangular or circular marquee, a magic wand or a selection brush. When the selection is made, it has an animated, dashed outline sometimes called ‘marching ants’.

Mask

Related to selections, but a more permanent way of masking out adjustments made to an image. For example, you might make an initial selection in an image-editor and then convert it into a layer mask which can be saved with the file and re-edited later if necessary.

Lasso tool

A simple selection tool where you drag an outline around the object or area you want to select. The selection is ‘closed’ and ready for use when you finish the loop back at the point where you started. The Lasso tool is not very accurate but when used in conjunction with other selection tools and editing processes it can nevertheless be very effective.

Feathering

A way of softening the edges of a selection or mask so that there’s no obvious boundary between the adjusted area, or a selected object, and the rest of the picture. Feather values are usually quoted in pixels.

Cutout

Where an object in a photo is cut out from its surroundings using a selection or a mask so that it can be added to another image or placed against a plain (usually white) background.

Brush

A simple manual tool for painting colour on to an image, making a selection or a mask, or applying an adjustment. You can change the size of the brush, its ‘hardness’ and its flow rate or opacity, all of which can help you adjust the effect and the way it’s built up.

Blending

Creating a smooth transition between one photo and another in a montage, or between areas where different adjustments have applied. A sharp division gives the photo an unnatural look, but blending in an adjustment smoothly looks more natural. One technique is to ‘feather’ a selection before making adjustments. Blending is often used with graduated or radial filter tools.