Museo&WebPlanning Kit for a Quality Site for Small and Medium Sized Museums |
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Digital imagesEvery digital image has 3 characteristics:
The Web uses 3 formats for compressing images:
NB. Overuse of images in the same page extends loading time. Text and images should therefore be balanced and the graphic potential of HTML should be used to the full. Take care not to insert heavy images (always remember to optimise files). Avoid overloading pages with too many images. Most users still navigate with analogical modems at 56Kbs and inserting too many images means creating pages that are slow and heavy to load. Playing with background colours and script is often enough to create a graphically attractive site. Save the image in desired size at 72 DPI.
Where possible, it is advisable to use thumbnail images. A thumbnail is simply a copy of a larger image. This copy has been modified to reduce the size of the file. A simple link to the larger image means that users can see the original image if they desire. Open
source software for creating thumbnails
When an image is inserted it is important to use the ALT function. This specifies the alternative text until the image is loaded or when it is not loaded at all. The Alt function is incredibly useful for making the site accessible to all users; Disabled users cannot see images clearly on the screen and could have problems if this function is not specified. If the description of the image is particularly long, then the synthetic description – supplied by the ALT function - can be extended thanks to another function: LONGDESC (long description). This specifies a file with a longer description of the image. Further notes on digitalisation of images:
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© Minerva
Project 2005-03, last revision 2005-03-06, edited by WP5, Committee for
the development of a prototype of public cultural websites. |