htaccess for image protection

[Martins]

I am close to launching a photography site and want to give some protection to my images. I have the following as a result of searching on the web:

#Set FollowSymLinks, in most cases already set on the server
Options +FollowSymLinks
#Enable Indexes
Options +Indexes
#Turn on the Rewrite Engine
RewriteEngine on
#Allow my domain
RewriteCond %{HTTP_REFERER} !^http(s)?://(www.)?mydomain.com [NC]
#Allow another domain
#RewriteCond %{HTTP_REFERER} !^http(s)?://(www.)?anotherdomain.com [NC]
#Allow blank referrers or delete this line to block them
#Deleting this line also blocks access to images by filepaths
RewriteCond %{HTTP_REFERER} !^$
#Allow search engines
RewriteCond %{HTTP_REFERER} !google. [NC]
RewriteCond %{HTTP_REFERER} !search?q=cache [NC]
RewriteCond %{HTTP_REFERER} !msn. [NC]
RewriteCond %{HTTP_REFERER} !yahoo. [NC]
#File types to be blocked
RewriteRule \.(jpg|jpeg|png|gif)$ - [NC,F,L]
#OR
#First allow an image to be hotlinked to avoid looping
#RewriteCond %{REQUEST_URI} !^mydomain.com/image/hotlinker.gif$
#Then display a custom image
#RewriteRule .(jpg|jpeg|png|gif)$ mydomain.com/image/hotlinker.gif [NC,R,L]

1) Is there a way to stop an image being called up by its file path that does not involve blocking blank referrers? I have a few instances where I would like to do this.

2) Do I have the correct code to allow Google, MSN and Yahoo proper access to my images?

3) The code I have is merged from more than one source. As I have no knowledge of the syntax, I’m wondering why only the RewriteRule without a substitute image starts with a \ .

Appreciate any feedback, thanks.