Providing Sufficient Color Contrast An important aspect of color on the Web for both low vision and color-blind users is sufficient contrast between foreground (text or graphics) and the background. When designing the color scheme of a website, web page, or document, be sure to consider whether there is sufficient contrast between foreground text and background. Guidelines WCAG 2.0 The WCAG 2.0 guideline 1.4.3 recommends the following luminosity ratio standard of 1 to 4.5 for main text and 1 to 3 for large-scale text (18 points+, or 14 points+ bold). NOTE: If your target audience is mostly low vision, then a ratio of 1 to 7 is recommended. • Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1; • Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement. • Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement.e Overview Some users have difficulty perceiving text if there is too little contrast between foreground and background. The W3C Web Content Accessibility Guidelines 2.0 define specific contrast ratios that must be met in order comply at particular levels. Our new 2013-2014 Training Schedule has just been released. If you are interested in taking advantage of this free training for your own children, or would like to volunteer in a classroom. In order to meet the guidelines at Level AA, text or images of text must have a contrast ratio of at least 4.5:1 (or 3:1 for large text). In order to meet the guidelines at the stricter Level AAA, the contrast ratio must be at least 7:1 (or 4.5:1 for large text). Testing for Contrast The is a website that provides an excellent companion to the Colour Contrast Analyser. Its most useful feature is a set of “Lighten” and “Darken” links that can be used to make subtle changes to existing colors until a Pass rating is attained. Additional Contrast Testing Tools • • • • • (Windows and Mac) •. Printer Interfaces Printers are connected to computers using a variety of different interfaces such as parallel, serial, SCSI, USB, or IEEE 1394. Network capable printers also have a built-in network interface and are connected directly to a port on the network so they can be shared across many computers. Parallel A parallel printer interface is called (IEEE 1284). This port works by sending an 8-bit information stream to the printer. How do i update my acer p610 maps for ireland - Acer P610 4 in. Car GPS Receiver question. Acer p610 software update. Acer's p610 Portable Navigator. CDs shows that the core software is Windows CE. The p610 does more than simply. To get them rectified in future updates. Aashiqui 2 dj remix mp3 songs download. It uses a standard parallel printer cable, which has a DB-25 connector to connect to the computer and also a 36-pin Centronics connector for the connection to the printer. The maximum length of the parallel cable is usually limited to 10 feet. The reason for this is that the data integrity decreases, and you can have loss of data to the printer over a larger length. Serial The serial printer interface sends the data to the printer one bit at a time. This interface needs to be configured to the serial communication parameters including baud rate, parity bit, or start and stop bits. ![]() ![]() Serial printers are very rarely used these days, however sometimes dot matrix printers use this interface. Universal Serial Bus (USB) The USB port is the most common type of port available on most pc's today. This is why it makes a great printer interface used on small and medium sized printers and desktop printers and scanners combo's.
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