How to disable access_log to images but log 404s

[Igal @ getRailo.org]

hi,

I am suppressing the access_log for images and other files in the /res/
directory:

     location ^~ /res/ {

        error_page  404  /res/images/100candles-logo-square.png;
        expires     14d;
        access_log  off;
    }

but I would like to log the 404s in the access_log

how can I do that?

TIA