this is what is being stated in the T&C of the YOG site
As a condition for entry to a Venue, each Ticket Holder grants perpetual permission to the IOC and SYOGOC and authorised third parties, without requirement of payment of any form, to use photographs, film, tape or other images of such Ticket Holder incidental to any live or recorded video display or transmission or reproduction in whole or part of the Event or Session which he attends.Each Ticket Holder agrees that images, videos and sound recordings of the Singapore 2010 Games obtained by such Ticket Holder with personal mobile phones, cameras, video and audio devices or other means will not be used for broadcast, publication, or any other commercial purposes under any circumstances, whether on the internet or otherwise.
so should be able to bring dslr inside