Detailed operation37TTL auto flash mode■ ■■ TTL auto flash: DIn this mode, the flash illumination that is reflected back from the subject isdetected by the camera’s TTL auto flash sensor and the camera automaticallycontrols the flash output level to give the correct exposure.Automatic Balanced Fill-Flash: DoPress the a button to display Do on the LCD panel, and AutomaticBalanced Fill-Flash is performed. The flash output level is automaticallyadjusted for a well-balanced exposure of the main subject and background.(While performing Balanced Fill-Flash, no o appears with cameras in GroupsIII and IV.)• Do indicates “i-TTL Automatic Balanced Fill-Flash” in the i-TTL mode.Standard TTL flash: DPress the a button to display D on the LCD panel, and Standard TTLflash is performed. The main subject is correctly exposed regardless of thebackground brightness. This is useful when you want to highlight the mainsubject.• D indicates “Standard i-TTL flash” in the i-TTL mode, “Standard TTL flash for DigitalSLRs” in the D-TTL mode, and “Standard TTL flash” in the TTL (film-based) mode.t Notes on TTL mode indicatorsComparison tables are provided on pages 108-110 to show the SB-800’s TTLmode indicators and the corresponding ones used in the instruction manuals ofSpeedlights featuring no CLS.• For details on shooting procedures in the TTL auto flash mode, refer to “Basic operation”(p. 17).t Flash shooting in the 1/300 TTL High-Speed Flash sync mode(F5 only)The farthest flash shooting distance cannot be read on the SB-800’s LCDpanel. In this case, use the guide number table and equation (p. 106) forcalculating this distance, according to each zoom-head position.