Andre,

Just stumbled across this post: http://stanleyjohns.wordpress.com/2012/01/09/reading-the-transaction-log-using-fn_dblog-and-fn_dump_dblog/

Talks about how to peek inside a log backup using fn_dump_dblog, which can show you what times are contained within. Completely unsupported and undocumeted function, so use entirely at your own risk etc. etc. 😉

But it was new to me, and seemed useful, so thought I'd share.

Cheers,

Tony.