About Photoshop

Adobe Photoshop is a graphics editing program developed and published by Adobe Systems.

Adobe's 2003 "Creative Suite" rebranding led to Adobe Photoshop 8's renaming to Adobe Photoshop CS. Thus, Adobe Photoshop CS6 is the 13th 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 released in two editions: Adobe Photoshop, and Adobe Photoshop Extended, with the Extended having extra 3D image creation, motion graphics editing, and advanced image analysis features.^[5] Adobe Photoshop Extended is included in all of Adobe's Creative Suite offerings except Design Standard, which includes the Adobe Photoshop edition.

Alongside Photoshop and Photoshop Extended, Adobe also publishes Photoshop Elements and Photoshop Lightroom, collectively called "The Adobe Photoshop Family". In 2008, Adobe released Adobe Photoshop Express, a free web-based image editing tool to edit photos directly on blogs and social networking sites; in 2011 a version was released for the Android operating system and the iOS operating system

Adobe only supports Windows and Macintosh versions of Photoshop, but using Wine, Photoshop CS5 can run reasonably well on GNU/Linux

About Photoshop You Must Know

Photoshop is, undeniably, one of the greatest software applications around. It has been around in one version or another for the last thirteen years, which is longer than I’ve known what CPU stands for.  Currently in its eighth version, it has so many functions and features that I simply couldn’t live with myself if I didn’t explain the 20 most important and useful ones to you.

Layer Sets

These are a way of organising or categorising common or linked layers in the layers panel. To create a new layer set, expand the Layer menu and select New -> Layer set. The new layer set dialogue box will appear and prompt you to enter a name for the new set. Once you have OK’d this box, a folder icon will appear in the layers panel; just drag and drop related layers into this folder. This is useful to organise your working environment and to apply styles across ranges of layers.  This functionality extends to slices in Imageready.

The Slice Tool

Residing in the toolbox that appears to the far left of your workspace, and denoted by the knife icon, the slice tool is essential for creating clickable rectangular regions of your image.  It is powered by Photoshop’s sister product Imageready (which comes bundled with the latest release of Photoshop), and needs to be used in Imageready to make the most of its potential.  Nevertheless, Photoshop lets you add actions when the region is rolled over or clicked, and can be extremely useful in the creation of roll-over image-swaps or expanding menus on image-driven web sites.  To create a slice, select the slice tool and drag a rectangle across the appropriate part of your image.  That’s it.  You can right-click the slice and select Edit Slice Options… to add URL, ALT and other information to the slice.  Slicing an image also decreases page load times; a couple of slices download quicker than one large image.

Image Maps
Image maps are very similar to slices in that you can use them to create roll-overs and hyperlinks. The main differences between slices and image maps are that slices must be rectangular, but image maps can be any shape. They are used only in Imageready, and have no effect on image download times.

Web Photo Gallery
This time-saving function can be found under File -> Automate -> Web Photo Gallery… and can be used to quickly put together a high quality, gallery of images in HTML format. You simply select a source directory, a target directory, and let Photoshop do the rest.  It creates as many web pages as needed to include all of the pictures in the source directory, which are presented in a tabular layout of thumbnails.  Additional parameters such as page titles and ALT text can also be specified. It even makes each image clickable and loads the full size version of the image in a page of its own when the thumbnail is clicked! This can be used to quickly create a product catalogue or portfolio.

Paste Into
Accessed via the Edit menu, this function inserts an image into another image, and crops the inner image to make it appear as if inside the outer image.  For example, you could draw a rounded rectangle 100 pixels wide and 20 pixels high and then draw another rounded rectangle 40 pixels wide and 20 pixels high directly on top of it.  You could then use the magic wand tool to select the area inside the smaller rectangle, and paste a photograph into the selected area.  Now only the area of the photograph within the smaller rectangle is visible.  Combined with some text, this makes an excellent web page heading.

Perspective Function
This is grouped with other similar functions under the Edit -> Transform Path menu and is used to add, surprisingly, a perspective effect.  It works best with angular images, but can also be used to add the appearance of movement. To use it, select the image you want to add perspective to and choose the function in the above menu. Your image will acquire a border with handles around the edge. Drag these handles in the appropriate direction to add the required amount of perspective.  Click the tick at the far right of the tool bar at the top of the screen when done.

Plugins
Plugins are like applets that can be installed in the plugins directory and used to add functionality to Photoshop. If there’s something you’re trying to do in Photoshop that is remotely difficult, there is probably a plugin that will help you do it more easily. They can be downloaded from numerous sources on the Internet and are often free.
Styles
The styles panel is a repository of pre-set effects; if you draw a shape and then double-click one of the styles, those effects are automatically applied to your shape. There are a number of different categories of styles which can be selected by clicking the right-facing arrow at the top of the panel. There are a number of web styles including push buttons and roll-overs, and they can save you huge amounts of time when creating forms or menus for your site.

Vector Graphics
For all of you out there who don’t know what vector images are (and I didn’t before I started playing around in Photoshop), they are basically images that can be endlessly scaled up or down with no loss in quality.  Absolutely none at all. In Paint, or any other basic bitmap imaging application, draw a circle. Unless you have a monitor that supports an extremely large resolution, it will look a bit blocky anyway, but now magnify the image by as little as ten times. You no longer have a circle; you have a polygon, or many-edged shape.
This does not happen with vector graphics. In Photoshop now, open a new image that is 640pixels wide and 480pixels and draw a circle.  Now select Image -> Image Size… and change the width to 16400pixels wide (the height should automatically adjust) and click OK. Find an edge, and it should appear just as smoothly as it did before the size increase. This is the essence of vectors, which makes them useful for images that are likely to be required in a range of sizes, such as logos.

The Preferences Dialogue Box
Located under Edit -> Preferences the preferences dialogue box is home to the environment settings that control how Photoshop behaves. You can control various settings, including; General, file handling, display and cursors, transparency and gamut, units and rulers, guides, grid and slices, plugins and scratch disks, memory and image caching and the file browser. If you wanted to change the colour of your guides, or allocate more memory to the application, this is where you would do it. Take a moment to have a look through all of the options available to you.

Shading with the Dodge and Burn Tools
Highlights and shading can be added to shapes with ease using the effects menu in the layers panel. But what if you only want to add shading to only part of your shape, or add highlights without lowlights?  Open a new page and draw a rounded rectangle, rasterize it, and select the burn tool (the one with the fist) from the toolbox. Click and drag the pointer over the bottom right of your shape to create instant lowlights. Now select the dodge tool (the lollipop), and repeat the process over the upper left of the shape to get some highlights. You may be a little sketchy to begin with but after a bit of practice, you’ll be able to add precision shading to images without even thinking about it.

The Window Menu
The Window menu is all about customizing your workspace and managing your panels. It’s about making your life easier. You use it to switch on available tool panels such as the layers panel or the character panel when they are needed. In addition to switching on or off tool panels as and when they necessary, it is also where you access the Workspace submenu. If you find yourself constantly closing certain panels and opening others as soon as Photoshop has loaded, you can save yourself the bother by saving the current workspace.  Your saved workspace then on appears in the Workspace menu.  You can also customise existing panels using the tabs at the top of each panel; if you wanted the history tools to be in the same panel as the layers, you simply click and drag the tab with History on it into the desired panel.

Scripts
Another time-saving tool here: the scripts function of Photoshop can be used to perform automated repetitive tasks, such as exporting all of your layers to PDF in order to produce a slideshow. Photoshop also contains its very own script debugger and will let you write your own Visual Basic or JavaScript scripts. Photoshop comes with many pre-written scripts that can be accessed via File -> Scripts -> Browse.  The scripting tools are supported by a number of PDF reference manuals in the Photoshop CS application folder so before taking on anything big, I suggest having a quick read through these.

Actions Manager
Similar in some ways, but nowhere near as powerful to the scripts function, the actions manager can be used to record and playback a series of menu or tool selections and actions, very much like the macro feature of Microsoft products. It comes with a vast library of pre-recorded actions which can be applied with a simple double-click. The actions panel should load into your workspace by default, and to record your own actions simply click the new action button and do whatever it is you need to do. You can set a name for your action and it will from then on appear as an action in the actions panel.

File Browser
The file browser is like a built-in Explorer that shows only pictures.   Well, mostly pictures; it also shows PDF files and zip files, but the PDF is obviously produced by Adobe and can therefore be used natively in Photoshop, and zip archives may well include pictures.  It is accessed by clicking the folder and magnifying glass icon at the top-right of the screen.
The Layers Panel
It’s hard to imagine using Photoshop at all without having the Layers panel present. Located at the bottom right of the workspace by default, it is home to all of your layers and some of the layer tools.  Layers can be switched on or off, making them visible or invisible respectively, or their opacity can be changed to alter their transparency. Both of these features are extremely useful when creating roll-overs or animations. Also, the layers panel is essential for adding effects to layers (see below).
 
Effects
Effects are very similar to styles in that they can uniformly change the appearance of your layers. The main difference between effects and styles is that effects are linked to the layer contents; when you change the layer, the effect changes with it. There is a pre-set selection of effects available to you, ranging from shadows and strokes (outlines), to gradient and pattern overlays.
 

Animation
Unfortunately, Photoshop cannot produce animated gifs; luckily, this is another area in which Imageready steps in and takes over.  In Imageready, open a new file and draw a shape.  Now select Window -> Animation to open the animation panel.   By default this should contain 1 frame, which is your image as it stands now.  Click the new frame button and the move the shape to the right slightly.  Keep adding new frames and gradually move your shape to the edge of the page.  There are some control buttons beneath the frames, click the play button and your shape should move across the screen.  That is as simple as animation can be, but not nearly as complex.  To save your animation, go into File -> Save optimised as… and save it as a gif.
Defringe Tool
Ever notice how an image with a transparent back can sometimes have a white edge, or fringe, around it?  This can be removed by selecting Layer -> Matting -> Defringe and ok’ing the default of 1 pixel.  This is not always 100% successful, and any minor discrepancies can usually be overcome by adding an inside stroke to the image, in the same colour as the edge of the image.

Save for Web
The save for web dialogue box, accessed via the File menu can be used to optimize your image for the web as much as possible. Combining the settings at the right of the dialogue box, it is possible to shave precious seconds off of your image download times. Lowering the amount of dither and increasing the amount of web snap both reduce file size, as does reducing the amount of colours and increasing the amount of lossy (when working with GIFs). Be warned however, image size goes hand in hand with image quality, the smaller the image, the lower the quality.

Conclusion
These are some of the tools and features that I find myself using on a regular basis when creating images for the web. Some of them you may embrace and use every time you open the program - others you may not find any use for at all.  Rest assured however, Photoshop remains of the industry standard when it comes to graphic and web design.

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