Be sure to check the photos themselves for copyright protection -
Electronic photographs have data tags called EXIF's for Extended Information File and are included in jpgs and other formats. Here is an example:
The picture came from an online auction five years ago - here is EXIF data on this 'borrowed' photo...
Image URL,http://www.otherpower.com/images/scimages/2861/AMERICAN20TSIDE.jpg
Image Description,None
Make,FUJIFILM
Model,FinePix2300
Exposure Time,Unknown
F Number,F4.8
Exposure Program,Normal program
Exposure Bias Value,0
Sensing Method,One-chip color area sensor
Shutter Speed Value,1/128
ISO Speed Rating,100
Subject Distance,Unknown
Metering Mode,Pattern
Flash,Flash did not fire
Lens Focal Length,5.8mm
White Balance,Unknown
DateTime Original,2001:09:05 18:33:40
EXIF Image Size(W*H),400 * 300
Software,FinePix Viewer Ver.1.1
EXIF Version,0210
Copyright,
People wanting to seperate their images from public domain usually will fill in the Copyright & Contact EXIF data areas, though people 'lifting' images via "copying" wipe out EXIF data, reading EXIFs is a best effort to build a clean web site. I know I wouldn't want to get a invoice for $250 because I used anothers picture...
Here are links to a plug-in that will read EXIFs straight from your web browser, works on Internet Explorer and Mozilla...
http://www.download.com/ViewEXIF/3000-2378_4-10129118.html
http://ak.no-ip.com/EXIF/
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