I get good traffic from Google image search. But I am also getting killed by bandwidth thieves hotlinking my pictures (I have a lot on my site). I hated to do it but I turned on hotlink protection. And right away I noticed the Google image bot getting blocked. Any advice on what to do? Google image search brings me a significant amount of traffic so I hate to kill that off.
If your webserver is apache and htaccess files support is enabled, then use htaccess to allow google and your own site to access images and block others by examining the HTTP_REFERER in htaccess. Search google to learn how to use htaccess.
Yes, I can add Google bots and other bots to the allowed list. Problem is, some of them give no referer. For example, my logs don't show a referer for the media bot (Mediapartners-Google/2.1) or for Yahoo! Slurp.
If an agent does not send the Referer header, it should be (and it is, i think) allowed to get the content, because any popular browser may also be configured to remove referers and perhaps Norton firewall also blocks referes. If this is not the case with your server, you can examine HTTP_USERAGENT (User-Agent header) in addition to Referer check to decide whether it should be allowed or not. Mediapartners-Google/2.1 is probably the useragent string.