Sections 3.5, 5.2.2 and 8.3.1 in Visual Methodologies all discuss searching for images online. Those sections raise a series of issues you should consider before working with images you have found online:
- online images may be designed to be online, or they may have been photographed in order to appear online. If the latter is the case, their visual and other qualities may have changed very significantly;
- all materials in online databases are organised and tagged in particular ways, that may not be apppropriate for your research;
- the criteria driving search engines are not visible, and may not produce straightforward results;
- the coverage of visual materials online may be patchy, or expensive.
You can discover more about tagging images in this paper by Peter Enser:
Free online article [via SAGE Journals Online]
For images on web pages, go to Google Images. The home page of Google Images allows you to do straightforward keyword searches; the 'Advanced Image Search' allows you to exclude certain keywords and look for keyword combinations.
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