Nikon D7100 Product Manual - Page 75

#P, S, A, and M Modes P, S, A, and M modes offer different degrees of control over shutter speed and aperture. Mode Description # Programmed auto (0 48): Camera sets shutter speed and aperture for optimal exposure. P Recommended for snapshots and in other situations in which there is little time to adjust camera settings. S Shutter-priority auto (0 49): User chooses shutter speed; camera selects aperture for best results. Use to freeze or blur motion. Aperture-priority auto (0 50): User chooses aperture; camera selects shutter speed for A best results. Use to blur background or bring both foreground and background into focus. M Manual (0 51): User controls both shutter speed and aperture. Set shutter speed to Bulb (A) or Time (%) for long time-exposures. A Lens Types When using a CPU lens equipped with an aperture ring (0 296), lock the aperture ring at the minimum aperture (highest f-number). Type G lenses are not equipped with an aperture ring. Non-CPU lenses can only be used in modes A (aperture-priority auto) and M (manual), when aperture can only be adjusted using the lens aperture ring. Selecting any other mode disables the shutter release. A Non-CPU Lenses (0 295) Use the lens aperture ring to adjust aperture. If the maximum aperture of the lens has been specified using the Non-CPU lens data item in setup menu (0 149) when a non-CPU lens is attached, the current f-number will be displayed in the viewfinder and control panel, rounded to the nearest full stop. Otherwise the aperture displays will show only the number of stops (F, with maximum aperture displayed as FA) and the f-number must be read from the lens aperture ring. 47