Nikon D70/D70s Users Guide
FLASH SYNC MODES
Select these by holding down the flash button on the left side of the flash hump and spinning the rear dial. Your selection is shown on the top LCD in the box with the bolt.
Normal (blank, which is the default): In Program and A exposure modes, the shutter won’t stay open longer than about 1/60 second. You can change this minimum speed in custom function 21, which defaults at about 1/60 second. I forget the exact default because I have mine set to 1/15.
In this mode you won’t get blur indoors, but you may not get more than a very black background either. Choose a longer speed, like 1/8, in CSM 21 to lighten the backgrounds indoors, but watch for motion.
I usually use Normal mode, since if I don’t I can get some scary long exposures if I’m not expecting them in the dark.
Red-Eye (eyeball icon): I never use this. It shines an obnoxious light in your subject’s eyes for a couple of seconds and then releases the shutter. If I set this mode by accident it bugs the heck out of me, because the camera doesn’t go off until several seconds after I’ve pressed the shutter, but I’ve set no self timer! It doesn’t do much to reduce redeye anyway. Skip this mode.
SLOW (called SLOW on the top LCD): This mode is very useful. It lets the shutter stay open as long as it needs to so dim ambient light can expose properly with flash. Of course if it’s dark these exposure times can get long. You can get blur from subject motion and camera shake. In daylight SLOW is the same as NORMAL, since exposure times are short. SLOW unlocks the camera in P and A exposure modes to make exposures as long as it wants to in dim light.
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