Learn About Photo Editing
Photo editing groups together several procedures for altering and correcting photographs, including image cropping, perspective control and noise reduction, among others. Graphic software programs, also known as photo editors, are the major tools used to enhance and transform images. Many photo editors are also used to render or create computer.
Cropping is a photo editing process for removing outer parts of an image to improve framing, enhance subject matter or alter aspect ratio. This may be achieved with digital photos by using photo editing software. Image cropping is performed in order to eliminate undesired subject or irrelevant details from a photo, modify its aspect ratio, or to improve the overall composition. In bird photography for example, an image is cropped to increase the main subject and further reduce the angle of view when a lens of sufficient focal length is not available. It is regarded as one of the few photo editing actions admissible in modern photojournalism along with tonal balance, color correction and sharpening. A crop made from the top and bottom of a photograph may create a mimicry of the panoramic format in photography and the widescreen format in cinematography and broadcasting.
Perspective control is a photo editing process for composing photographs to better fit the generally accepted distortions in constructed perspective. In other words, it would make all lines that are vertical in reality vertical in the image, including columns, vertical edges of walls and lampposts; and make all parallel lines cross in one point. Perspective projection distortion occurs in photographs when the film plane is not parallel to lines that are required to be parallel in the photo. A common case is when a photo is taken of a tall building from ground level by tilting the camera backwards, so the building appears to fall away from the camera. The increase of amateur photography has made distorted photos taken with cheap cameras so usual that most people do not immediately recognize the distortion. Photo editors such as Adobe Photoshop and GIMP offer feature different options for achieving perspective control with little to none image quality deterioration.
Digital photos can pick up noise from an array of sources. Salt and pepper noise is due to sparse light and dark disturbances, resulting in pixels in the image turning very different in color or intensity from their surrounding pixels. This type of noise will generally only affect a small number of image pixels. When viewed, the image contains dark and white dots, thus originating the term. Usual sources include flecks of dust inside the camera and overheated or faulty CCD elements. In Gaussian noise, on the other hand, each pixel in the image will be changed from its original value by a small amount. This two types of noises can be removed using photo editing noise reduction software, included in photo editors such as Adobe Photoshop, GIMP, PhotoImpact, Paint Shop Pro, and Helicon Filter.