This is a low quality picture I know, but still worthy of showing!  My biggest crappie to date at 15.5".  The picture was a couple winters ago on a metro lake, the fish house is pretty dark and only had my camera phone.  Fish bit around 10pm on a jig in shallow water.  A lot of the slabs we get come late at night, so be patient and give the late night bite a try, 10 to 2am has been a good window for slab action on ice!