Nikon D5300 Reference Manual - Page 201

❚❚ Auto ISO Sensitivity control If Off is chosen for Auto ISO sensitivity control in P, S, A, and M modes, ISO sensitivity will remain fixed at the value selected by the user (0 67). When On is chosen, ISO sensitivity will automatically be adjusted if optimal exposure can not be achieved at the value selected by the user. The maximum value for auto ISO sensitivity can be selected using the Maximum sensitivity option in the Auto ISO sensitivity control menu (choose lower values to prevent noise (randomly-spaced bright pixels, fog, or lines, but note that if the ISO sensitivity selected by the user is higher than that chosen for Maximum sensitivity, the value selected by the user will be used instead; the minimum value for auto ISO sensitivity is automatically set to ISO 100)). In modes P and A, sensitivity will only be adjusted if underexposure would result at the shutter speed selected for Minimum shutter speed (1/2000-1 s, or Auto; in modes S and M, sensitivity will be adjusted for optimal exposure at the shutter speed selected by the user). If Auto (available only with CPU lenses) is selected, the camera will choose the minimum shutter speed based on the focal length of the lens (auto shutter-speed selection can be fine-tuned by highlighting Auto and pressing 2). Slower shutter speeds will be used only if optimum exposure can not be achieved at the ISO sensitivity value selected for Maximum sensitivity. When On is selected, the viewfinder shows ISO-AUTO and the information display ISO-A. These indicators flash when sensitivity is altered from the value selected by the user. A Maximum Sensitivity/Minimum Shutter Speed When auto ISO sensitivity control is enabled, the ISO sensitivity and shutter speed graphics in the information display show the maximum sensitivity and minimum shutter speed. Minimum shutter speed Maximum sensitivity A Auto ISO Sensitivity Control Noise (randomly-spaced bright pixels, fog, or lines) is more likely at higher sensitivities. Use the High ISO NR option in the shooting menu to reduce noise (0 180). Note that ISO sensitivity may be raised automatically when auto ISO sensitivity control is used in combination with slow sync flash modes (available with the built-in flash and the optional flash units listed on page 232), possibly preventing the camera from selecting slow shutter speeds. Auto ISO sensitivity control is available only in i-TTL flash control mode (0 192, 233); in other modes, the value selected for ISO sensitivity will be used for pictures taken with the built-in flash or optional flash units. C The Shooting Menu: Shooting Options 181