Loading external images (from external domains)

Hello kirupa users :beer2:

I had a small problem in my latest work project where i wanted to load images from external domains.
The problem was that i did not know if i really need the checkPolicyFile set to true or if i really need to load the crossdomain.xml to tell flash player where the acces is.
As far as i know, in adobe as3 reference they stated that in order to load images from an external domain (a domain other than the one where the actual swf runs) you need a policy file or a security acces file in order to be able to do that.

My question is:
1: could i load an image from external domains without having to load some external file (or the crossdomain.xml file)?
2: if there is no possibility to load an image without the crossdomain policy why the checkPolicyFile method could take the value of false?

Thanks in advanced!

Regards.