Didn't know about this! Frank would have been almost 70 when he recorded this and he sounds great! And what a band! George Benson and the Brecker Brothers, just to mention a few. (I haven't watched the whole doc yet but the IMDB cast list seems a little off, at least it doesn't mention Ray Brown on bass.) Watch it on Amazon.
Filmed in 1984, Portrait Of An Album follows Frank Sinatra as he records his album L.A. Is My Lady with producer Quincy Jones, who also conducts the sessions.