Image search and CDNs

[NicB1]

Hi,

Our site has a very high domain strength.  Although our site ranks well for general search phrases, we rank poorly for image search (even though our site has very high quality images). Our images are hosted on a separate CDN with a different domain.  Although there are a number of benefits to doing this, since they are on a different domain, are we not able to capitalize on our my site's domain strength?  Is there any way to associate our CDN to our main site via Google webmaster tools?  Has anyone researched the search ranking impacts due to storing your images on a CDN, given that your domain strength is very high?

Curious on people's thoughts?

[caseyhen]

Hi NicB1,

We use Amazon CloudFront here at SEOmoz and it allows us to setup a CNAME for our CDN. So if you look at our images you will see we use a few different ones, such as cdn.seomoz.org, profile1.seomoz.org and profile2.seomoz.org. While I haven't done any studies on this, I can tell you that we have not seen a major change in image traffic in making the CDN switch a few months ago.

I'd check with your CDN people and see if you can setup a CNAME and place it on a subdomain.

Casey

[AlanBleiweiss]

I'll leave it to others who might have done serious testing on this to discuss findings.  I will say this though - if the CDN is not a domain you own, or can readily show through other optimization efforts that you own it, it's at least partly a matter of "how do we know this site owns these images?".  Purely from SEO best practices thinking, when a site hosts their images, there's a much lower threshold of being able to have them recognized for consideration, let alone associated with image names, alt attributes, and page topical focus.