Activity 12 : Photoshop and Web




Things you should know about Adobe Photoshop when creating a website:

  • As Photoshop’s memory requirements increase,
  • CTRL TAB:  Press CTRL Tab will allow you to switch between documents. If you are working on more than one document in Photoshop, you can press CTRL Tab on your keyboard to go to another document. You may need to press CTRL Tab a few times to get to the document you want.
  • The GIF89a format:  Basic animation was added to the GIF89a spec via the Graphics Control Extension (GCE), which allows various images (frames) in the file to be painted with time delays. An animated GIF file comprises a number of frames that are displayed in succession, each introduced by its own GCE, which gives the time delay to wait after the frame is drawn. Global information at the start of the file applies by default to all frames. The data is stream-oriented, so the file-offset of the start of each GCE depends on the length of preceding data. Within each frame the LZW-coded image data is arranged in sub-blocks of up to 255 bytes; the size of each sub-block is declared by the byte that precedes it.By default, however, an animation displays the sequence of frames only once, stopping when the last frame is displayed. Since GIF is designed to allow users to define new blocks, Netscape in the 1990s used the Application Extension block (intended to allow vendors to add application-specific information to the GIF file) to implement the Netscape Application Block (NAB).[8] This block, placed immediately before all the animation frames, specifies the number of times the sequence of frames should be played. (The value 0 signifies continuous display.) Support for these repeating animations first appeared in Netscape Navigator version 2.0, and then spread to other browsers.[9] Most browsers now recognize and support NAB, though it is not strictly part of the GIF89a specification. source:  wikipedia
  • Interpolation method: The idea behind Interpolation is to increase the file size of an image without creating a pixelated look for the finished product. Interpolation is the act of increasing the number of pixels based on the original pixel information and is generally used when trying to make large print from a high quality, but relatively small image.
  • Rasterizing:One of the advantages of working in Photoshop is the large number of built-in and plug-in filters that are available. Being able to apply filters to a layer can improve the speed and quality of your work. But if the layer contains text, vector graphics imported from another program or shapes produced by the Pen tool, you won’t be able to apply filters or paint fills to it. The layer needs to be rasterized
  • navigator panel
  • vector file format rasterize
  • JPEG have and how many colours are supported,
  • duotone: Duotones increase the tonal range of a grayscale image. Although a grayscale reproduction can display up to 256 levels of gray, a printing press can reproduce only about 50 levels of gray per ink. For this reason, a grayscale image printed with only black ink can look significantly coarser than the same image printed with two, three, or four inks, each individual ink reproducing up to 50 levels of gray.Sometimes duotones are printed using a black ink and a gray ink—the black for shadows and the gray for midtones and highlights. More frequently, duotones are printed using a colored ink for the highlight color. This technique produces an image with a slight tint and significantly increases the dynamic range of the image. Duotones are ideal for two?color print jobs with a spot color (such as a PANTONE Color) used for accent.
  • A snapshot represents the state of an image at a particular moment in time and is represented by a thumbnail of the image.
  • Hue: Hue and Saturation adjustments provide an immediate and effective way to alter or adjust the appearance of your image.
  • Resampling (or interpolation):  Changing the number of pixels in the image.





  •  Continue working on Unit 1/Activity 11 but you may use Photoshop instead of Fireworks.


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