Slecting the shutter speed.

Slow shutter speed : Set the higher shutter dial at the top panel at "25-1" first, and then select one of the slow shutter speed with the slow shutter dial at the front.

Higher shutter speed : Set the slow shutter dial at the front at "25" first (Stopper fixes the dial by this.), and then set one of the higher shutter speed with raising the higher shutter dial, and at the same time turining it.