Good quality outside the flash and flash lights have no difference between good and bad, outside the light output much larger. SLR with the so-called high-speed synchronization lights are some problems, really want to use a higher shutter speed have to rely on a higher synchronization speed using the mirror between the camera shutter. In the indoor use of good outside light if the output is relatively low, in fact, it can be very good solidification of high-speed moving objects, and the camera's shutter speed is not much relationship. Light soft or hard does not exist good or bad points, look at your shooting needs, using different accessories to get different light quality.