I figured it out!!
I added this piece of jQuery:
<script type="text/javascript">
<!--
$(function() {
jQuery(".photos a").hover(function() {
var offset = $(this).offset();
var id_post = $(this).attr("id");
jQuery(".hover").find("span[id="+id_post+"]").css("left", (offset.left-312)+"px");
jQuery(".hover").find("span[id="+id_post+"]").show();
}, function() {
jQuery(".hover").find("span").hide();
})
});
//-->
</script>
and added an additional loop:
<div class="hover">
<?php query_posts( 'category_name=photos&posts_per_page=-1' ); ?>
<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
<span id="<?php echo $post->ID; ?>"><?php the_post_thumbnail("carousel-full"); ?></span>
<?php endwhile; endif; ?>
<?php wp_reset_query(); ?>
</div>
and presto!!