Konsole starten - links "Alle Meldungen" auswählen und rechts im Filter (Suchfeld) com.apple.backupd eintragen
Dann sollten auch hilfreiche Sachen zu lesen sein.....
Bei mir sieht der Log eines Backups zB so aus:
31.10.12 12:17:45,955 com.apple.backupd[69205]: Starting manual backup
31.10.12 12:17:46,396 com.apple.backupd[69205]: Attempting to mount network destination URL: afp://xxxxxxx;AUTH=SRP@TimeCapsule.local/Backup
31.10.12 12:17:46,896 com.apple.backupd[69205]: Mounted network destination at mount point: /Volumes/Backup using URL: afp://xxxxxxxx;AUTH=SRP@TimeCapsule.local/Backup
31.10.12 12:18:18,953 com.apple.backupd[69205]: Disk image /Volumes/Backup/xxxxxxs iMac.sparsebundle mounted at: /Volumes/Time Machine-Backups
31.10.12 12:18:18,968 com.apple.backupd[69205]: Backing up to: /Volumes/Time Machine-Backups/Backups.backupdb
31.10.12 12:18:23,818 com.apple.backupd[69205]: Using file event preflight for Macintosh SSD
31.10.12 12:18:32,700 com.apple.backupd[69205]: Will copy (9,4 MB) from Macintosh SSD
31.10.12 12:18:32,703 com.apple.backupd[69205]: Using file event preflight for Macintosh HD
31.10.12 12:18:32,703 com.apple.backupd[69205]: Will copy (Zero KB) from Macintosh HD
31.10.12 12:18:32,704 com.apple.backupd[69205]: Found 90 files (9,4 MB) needing backup
31.10.12 12:18:32,730 com.apple.backupd[69205]: 1,3 GB required (including padding), 849,25 GB available
31.10.12 12:19:47,261 com.apple.backupd[69205]: Copied 1930 files (9,4 MB) from volume Macintosh SSD.
31.10.12 12:19:52,256 com.apple.backupd[69205]: Copied 1940 files (9,4 MB) from volume Macintosh HD.
31.10.12 12:19:52,395 com.apple.backupd[69205]: Using file event preflight for Macintosh SSD
31.10.12 12:19:52,404 com.apple.backupd[69205]: Will copy (2,3 MB) from Macintosh SSD
31.10.12 12:19:52,408 com.apple.backupd[69205]: Found 41 files (2,3 MB) needing backup
31.10.12 12:19:52,409 com.apple.backupd[69205]: 1,29 GB required (including padding), 849,25 GB available
31.10.12 12:20:08,255 com.apple.backupd[69205]: Copied 1506 files (2,3 MB) from volume Macintosh SSD.
31.10.12 12:20:12,519 com.apple.backupd[69205]: Copied 1516 files (2,3 MB) from volume Macintosh HD.
31.10.12 12:20:13,424 com.apple.backupd[69205]: Created new backup: 2012-10-31-122012
31.10.12 12:20:17,062 com.apple.backupd[69205]: Starting post-backup thinning
31.10.12 12:20:17,063 com.apple.backupd[69205]: No post-back up thinning needed: no expired backups exist
31.10.12 12:20:17,517 com.apple.backupd[69205]: Backup completed successfully.
31.10.12 12:20:22,299 com.apple.backupd[69205]: Ejected Time Machine disk image: /Volumes/Backup/xxxxxs iMac.sparsebundle
31.10.12 12:20:22,626 com.apple.backupd[69205]: Ejected Time Machine network volume.