Adobe Photoshop, or simply Photoshop, is a graphics editing program developed and published by Adobe Systems. It is the current market leader for commercial bitmap and image manipulation software, and is the flagship product of Adobe Systems. It has been described as “an industry standard for graphics professionals” and was one of the early “killer applications” on the Macintosh, later also for the PC. Adobe’s 2005 “Creative Suite” rebranding led to Adobe Photoshop 8’s renaming to Adobe Photoshop CS. Thus, Adobe Photoshop CS4 is the 11th major release of Adobe Photoshop.
The CS rebranding also resulted in Adobe offering numerous software packages containing multiple Adobe programs for a reduced price. Adobe Photoshop is included in most of Adobe’s Creative Suite offerings. FEATURES Photoshop has strong ties with other Adobe software for media editing, animation, and authoring. The . PSD (Photoshop Document), Photoshop’s native format, stores an image with support for most imaging options available in Photoshop. These include layers with masks, color spaces, ICC profiles, transparency, text, alpha channels and spot colors, clipping paths, and duotone settings.
This is in contrast to many other file formats (e. g. .EPS or . GIF) that restrict content to provide streamlined, predictable functionality. Photoshop’s popularity means that the . PSD format is widely used, and it is supported to some extent by most competing software. The . PSD file format can be exported to and from Adobe Illustrator, Adobe Premiere Pro, and After Effects, to make professional standard DVDs and provide non-linear editing and special effects services, such as backgrounds, textures, and so on, for television, film, and the Web.
Photoshop is a pixel-based image editor, unlike Adobe Illustrator or CorelDraw, which is a vector-based image editor. Photoshop can utilize the color models RGB (red, green, blue), lab, CMYK (cyan, magenta, yellow, key), grayscale, binary bitmap, and duotone. Photoshop has the ability to read and write raster and vector image formats such as . EPS, . PNG, . GIF (Graphic Interchange Format), . JPEG (Joint Photographic Experts Group), and Adobe Fireworks. CS3 (Creative Suite 3) Photoshop CS3 is marketed with three main components of improvement over revious versions: “Work more productively, edit with unrivalled power, and composite with breakthrough tools. “New features propagating productivity include streamlined interface, improved Camera Raw, better control over print options, enhanced PDF support, and better management with Adobe Bridge. Editing tools new to CS3 are the Clone Source palette and nondestructive Smart Filters, and other features such as the Brightness/Contrast adjustment and Vanishing Point module were enhanced. The Black and White adjustment option improves users control over manual grayscale conversions with a dialog box similar to that of Channel Mixer.
Compositing is assisted with Photoshop’s new Quick Selection and Refine Edge tools and improved image stitching technology. IMAGE An image is an artifact, for example a two-dimensional picture, that has a similar appearance to some subject—usually a physical object or a person. Images may be two-dimensional, such as a photograph, screen display, and as well as a three-dimensional, such as a statue. They may be captured by optical devices—such as cameras, mirrors, lenses, telescopes, microscopes, etc. and natural objects and phenomena, such as the human eye or water surfaces.
The word image is also used in the broader sense of any two-dimensional figure such as a map, a graph, a pie chart, or an abstract painting. In this wider sense, images can also be rendered manually, such as by drawing, painting, carving, rendered automatically by printing or computer graphics technology, or developed by a combination of methods, especially in a pseudo-photograph. BITMAP In computer graphics, a raster graphics image or bitmap is a data structure representing a generally rectangular grid of pixels, or points of color, viewable via a monitor, paper, or other display medium.
Raster images are stored in image files with varying formats (see Comparison of graphics file formats). A bitmap corresponds bit-for-bit with an image displayed on a screen, generally in the same format used for storage in the display’s video memory, or maybe as a device-independent bitmap. A bitmap is technically characterized by the width and height of the image in pixels and by the number of bits per pixel (a color depth, which determines the number of colors it can represent). The printing and prepress industries know raster graphics as contones (from “continuous tones”) and refer to vector graphics as “line work”.
VECTOR Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon(s), which are all based on mathematical equations, to represent images in computer graphics. Vector graphics formats are complementary to raster graphics, which is the representation of images as an array of pixels, as it is typically used for the representation of photographic images. There are instances when working with vector tools and formats is best practice, and instances when working with raster tools and formats is best practice.
There are times when both formats come together. An understanding of the advantages and limitations of each technology and the relationship between them is most likely to result in efficient and effective use of tools. Resolution Raster graphics are resolution dependent. They cannot scale up to an arbitrary resolution without loss of apparent quality. This property contrasts with the capabilities of vector graphics, which easily scale up to the quality of the device rendering them.
Raster graphics deal more practically than vector graphics with photographs and photo-realistic images, while vector graphics often serve better for typesetting or for graphic design. Modern computer-monitors typically display about 72 to 130 pixels per inch (PPI), and some modern consumer printers can resolve 2400 dots per inch (DPI) or more; determining the most appropriate image resolution for a given printer-resolution can pose difficulties, since printed output may have a greater level of detail than a viewer can discern on a monitor.
Typically, a resolution of 150 to 300 pixel per inch works well for 4-color process (CMYK) printing. FILE FORMATS PSD – (Photoshop Document)The PSD file extension is the file extension used in documents created using the Adobe Photoshop software. The Adobe Photoshop application is the most commonly used editing program for professional images. This program may include adjustment layers, image layers, annotation notes, layer masks, keywords, file information, as well as other specific elements of Adobe Photoshop. EPS – Encapsulated PostScript, or EPS, is a
DSC-conforming PostScript document with additional restrictions intended to make EPS files usable as a graphics file format. In other words, EPS files are more-or-less self-contained, reasonably predictable PostScript documents that describe an image or drawing, that can be placed within another PostScript document. PNG – Portable Network Graphics (PNG) is a bitmapped image format that employs lossless data compression. PNG was created to improve upon and replace GIF (Graphics Interchange Format) as an image-file format not requiring a patent license.
The PNG acronym is optionally recursive, unofficially standing for “PNG’s Not GIF”. PNG supports palette-based (palettes of 24-bit RGB or 32-bit RGBA colors), greyscale, RGB, or RGBA images. PNG was designed for transferring images on the Internet, not professional graphics, and so does not support other color spaces (such as CMYK). GIF – The Graphics Interchange Format (GIF) is a bitmap image format that was introduced by CompuServe in 1987 and has since come into widespread usage on the World Wide Web due to its wide support and portability.
The format supports up to 8 bits per pixel, allowing a single image to reference a palette of up to 256 distinct colors chosen from the 24-bit RGB color space. It also supports animations and allows a separate palette of 256 colors for each frame. The color limitation makes the GIF format unsuitable for reproducing color photographs and other images with continuous color, but it is well-suited for simpler images such as graphics or logos with solid areas of color.
PDF – Portable Document Format (PDF) is a file format created by Adobe Systems in 1993 for document exchange. PDF is used for representing two-dimensional documents in a manner independent of the application software, hardware, and operating system. Each PDF file encapsulates a complete description of a fixed-layout 2D document (and, with Acrobat 3D, embedded 3D documents using U3D) that includes the text, fonts, images, and 2D vector graphics which compose the documents. WORKSPACE A.
Document window – displays the file you’re working on. B. Dock of panels collapsed to icons – default opened palette for navigator, color and layers C. panel title bar – displays the tab name of each palette D. menu bar – organizes commands under menus E. options bar – displays options for the currently selected tool. F. tools palette – contains tool for creating and editing images, artwork, page elements, and so on. Related tools are grouped together. G. collapse to icons button – button used to collapse palettes into icons H. loating palettes – help you monitor and modify your work. Shortcut KeysFunction 1. ]increase brush size 2. [decrease brush size 3. Ctrl+shift+Iinvert selection 4. Ctrl+ddeselect 5. Ctrl+jduplicate single layer 6. Ctrl+alt+zundo several times 7. F7hide/unhide layers panel 8. Tabhide/unhide toolbar, options bar, palettes 9. Fchange screen mode/display 10. Ctrl+tfree transform (resize, rotate, flip) 11. Ctrl++zoom in 12. Ctrl+-zoom out 13. Space bar+left mouse clickpanning