You must be using aperture priority (which I normally use, as well). When you use aperture priority with flash, it sets the shutter at 1/60 ALWAYS. You cannot change that, and then you set aperture to effect DoF/allow enough flash power into the scene.
Instead, put it in manual mode, which is more useful for these scenarios anyway. The light will function as a fill. Set your shutter speed to determine ambient, then set your aperture however you want it, since the TTL will power itself appropriately for the scene. For better battery life, obviously open things up or increase ISO, or if you're not worried about that, just set aperture for your DoF.
ETA: Be aware that if you have AutoFP set on your SB900, it will automatically enable you to increase your shutter up to 1/8000. Be aware that any speed above 1/320 (and possibly 1/250 for the D700) will dramatically decrease flash power as a result of how Auto FP is achieved.
Message edited by author 2011-07-26 23:29:29. |
