Photoshop Photoshop works with bitmapped, digitized images (that is, continuous-tone images that have been converted into a series of small squares, or picture elements, called pixels). You can also work with vector graphics, which are drawings made of smooth lines that retain their crispness when scaled. You can create original artwork in Photoshop, or you can import images into the program from many sources, such as: • Photographs from a digital camera. • Commercial CDs of digital images. • Scans of photographs, transparencies, negatives, graphics, or other documents. • Captured video images. • Artwork created in drawing programs.

Pixels It's measured in terms of ppi, or 'pixels per inch' when viewed in an image or on the monitor. It's referred to as dpi or 'dots per inch' in terms of printing. Files you open in Elements are composed of thousands maybe millions of tiny square pixels. Each pixel has one and only one, colour value The arrangement of the pixels of different shades and colours creates an illusion to your eyes that you are viewing an image on screen

Raster and Vector images When you have pixels you have RASTER images. If you opened up a file that didn’t have pixels -then Photoshop would have to rasterize the data- converting the data into pixels VECTOR describes a shape mathematically-The shapes comprise paths made up of lines, curves and anchor paths. One advantage is that they have smooth edges, they also can be resized without any lose of quality

Shape tools are vector images These can be used to create a simple logo or a web button Type is initially created as a vector graphic. Vector type provides scalable outlines that can be resized without producing jagged outlines. It always prints with optimal quality- crisp and clean When you simplify the text it rasterizes it and turns ito pixels. You cannot edit it like text, but you can apply filters and special effects.

Tools in the Toolbox The Vector Tools allow users to create vector-based objects in Photoshop. Unfortunately, this is a tool bar from Photoshop. Photoshop elements does not have the pen tool, but we do have a pencil and brush tool.

Resolution Any way you call it, resolution determines how the image will appear on the screen and how it will print -- more importantly, how the pixels are distributed in the document Resolution is the number of units that occupy a linear inch in an image. If you have 72 pixels across a 1” horizontal line, your image is 72 pixels per inch (ppi). If you have 300 pixels across a 1” horizontal line your image is _______(ppi).

Setting Image size Resolution is the number of pixels or dots per inch (ppi/dpi). The higher the resolution, the more detail is stored for the graphic. This means that a higher resolution image is higher quality, but also is a larger in size.

Black and White printing Setting Image size Web Graphics 72 dpi Low-end printing 150 dpi Black and White printing 266 dpi When printing- If the resolution is too low, the image prints poorly. If the resolution is too high, you files are too large and it will not print any better if you printer can only process 300 dpi, Professional quality printing 300 dpi

Setting Image size Web Graphics 72 dpi The computer monitor displays everything you see on it in a fixed resolution.- this is set at 72 ppi. That’s all you get. What’s important to remember is the best veiwing of your photos is images at 72 ppi in a 100% view. As you zoom in the image is more pixilated.

Quality Colour Print -300 dpi Web images -72 dpi Black and White -266 dpi Quality Colour Print -300 dpi The camera shoots at 72 dpi but the images are large (35 in x 26 in my camera) Photoshop compresses these pixels and makes them smaller- you can make it 300 dpi but it will be a smaller picture If you increase the size and keep the resolution the pixel squares just get bigger and it becomes fuzzy

Once the Resolution is made lower Setting Image size Once the Resolution is made lower Cannot be revert Width and height- can be seen in percents, inches, centimetres, millimetres, points, picas, or columns

For printing If you uncheck the Resample the image, and change it to 300 ppi, The original pixels will not be changed but the image will be smaller in size. This is preferable in printing as Photoshop will not be guessing and adding their own pixels, Note the image memory size is the same. If you want it bigger then uncheck resample image and Photoshop will add pixels and the image memory size will increase.

Changing Size, but not Resolution for Web Images Click IMAGE-> IMAGE SIZE Make sure there is a check in Resample Image "Resample Image" instructs PhotoShop to keep the resolution the same, no matter what you do to the size. If you make an image bigger, PhotoShop will have to add pixels. If you shrink the image, PhotoShop will have to remove pixels. There are three resample image choices. Use "Bicubic" its the best. Change the Pixel Dimensions of the image, not the print size. Click OK  

Changing Resolution (but not size) for Web Images Sometimes you’ll have an image that was scanned at a higher or lower resolution than you need. Its size is fine, youll only need to change the resolution. Click IMAGE-> IMAGE SIZE Uncheck Resample Image Change the Resolution to 72 Since we are not printing in this class. The resolution for all are work does not have to be larger that 72 ppi.

File Formats Bitmap formats include Vector formats include • BMP • GIF • JPEG, JPG • PNG • PICT (Macintosh) • PCX • TIFF • PSD (Adobe Photoshop) Bitmap editing programs • Microsoft Paint • Adobe Photoshop • Corel Photo-Paint • Corel Paint Shop Pro • The GIMP Vector formats include • AI (Adobe Illustrator) • CDR (CorelDRAW) • CMX (Corel Exchange) • CGM Computer Graphics Metafile • DXF AutoCAD • WMF Windows Metafile Vector drawing programs • Adobe Illustrator • CorelDRAW • Xara Xtreme • Serif DrawPlus

Common File Formats PSD (Photoshop Data) files preserve layer and channel information, users can continually edit and adjust images using the PSD file. JPEG (Joint Photographic Experts Group) Every time a JPEG file is saved, the file recompresses and make a lighter file size but losses quality. TIFF (Tagged Image File Format) files are not compressed format and make larger file size. Widely used for printing/publication purposes. GIF (CompuServe Graphic Interchange Format) files are most commonly used for Web-based line art such as logos and buttons since this format can only support a maximum of 256 colors and lighter in size. (and retains transparent backgrounds in web design and Flash) BMP (Bitmap) files are mostly used in windows paint program.