BIND logging

I want to enable BIND logging so that I can monitor how many dns requests my dns server is doing. So in my named.conf file I put the following entries:

logging{
        channel simple_log {
                file "/var/log/named/bind.log" versions 3 size 5m;
                severity info;
                print-category yes;
                print-severity yes;
                print-time yes;
                };
        category default {
                simple_log;
                };
};


I tried using touch to make the inital file and I have also left the directory listed above empty.

But nothing goes into the log... What do I need to add to my named.conf file to see any and log all DNS requests?