Only allowing positive votes

[marian]

I would like to make it so that people can only give a good, or better vote. The reason is that we seem to have a couple of gallery viewers who regularly give pix, by well known photographers, a 0 vote as soon as they appear. I think this is deliberate and may be intended to put well-known people off letting us use their pix.
Here is an example of a pic that got two 0 votes as soon as it was posted! http://bymnews.com/photos/displayimage.php?pos=-10299 yet I dont think it could possibly be described as "rubbish".
Please could someone tell me how to make this mod?

[Nibbler]

It's probably bots, search the board for previous discussion on this or just disable anonymous voting.

[marian]

It's probably bots, search the board for previous discussion on this or just disable anonymous voting.

Sorry, I should have searched first - my apologies, excuse is being up to eyes in it!
I didn't realise bots could actually vote, though I've often seen them trying to, like I've seen them trying to post on the forum!!
Dont want to disable if poss; we dont have members, so everyone is anon. I'll go search.

[Joachim Müller]

keep google spider (and maybe some others) from voting by adding rel="nofollow" to the voting links.

[marian]

keep google spider (and maybe some others) from voting by adding rel="nofollow" to the voting links.

Many tks