Are there any tricks which wont violate the TOS that one can use to get a little more relevant ads showing on pages with very little text?
You mean more ads and fewer content? Wouldn't it be classified as MFA site. I'd keep a balance with both.
He might be referring to pages that primarily have videos or images, in which case you can probably solve your problem, at least from a contextual relevancy standpoint, by including a small description area of a few sentences. Alternatively, make good use of the H1 and TITLE tags. These can really help resolve contextual uncertainty. Images and videos in aqnd of themselves are perfectly legal and not against the TOS as they are still valid content.
Yeah it's for the public gallery pages on my image hosting site, very little text other than the album/user name and image file name. People tend not to enter descriptions for their images. AdSense seems to be picking up "xenon kits" from a footer text link to another site which I don't really want.
Include a brief paragraph at the bottom of each page, containing your keywords. Also, as has already been mentioned, be sure to include ALT tags. The META tags of the page will also be useful in determining the ads that show.
Thanks guys, will try those suggestions, maybe I'll be able to average 1 click a day after those changes