Mayor Paul Soglin is backing an ordinance which would require all Madison convenience stores to install quality security cameras.  Soglin says the move would improve public safety, save lives and make it easier to catch criminals in areas of the city identified as hot spots for crime.  The cameras would have to create high-quality images and include a date and time stamp.  The stores would retain the records for 30 days.  Many stores already have security cameras, but they may not meet the required standards.  If the city council passes the ordinance, it would go into effect about six months later.