Nikon 1683 Instruction Manual - Page 18

-CONTROLS IN DETAIL-continued--------- •. , " - •• .:.-:: '. I . ASAIISO film speed dial ® The ASAIISO scale on the dial has numbered settings for speeds from ASAIISO 12 to 6400. The dots between each pair of ASAIISO numbers stand for intermediate settings, such as 64, 80, etc. The illustration above gives the speeds for all intermediate settings. ASAIISO 100 and 400 are indicated in red as they are used quite often . ASAIISO is a numerical rating of the film 's sensitivity to a given amount of light. The higher the number, the greater the sensitivity, and vice versa. The ASAIISO of your film is indicated on the cartridge itself. It is also printed on the film carton and on the data sheet packed inside. Shutter speed dial ® 'exposure determination Setting the shutter speed To set the shutter speed, turn the shutter speed dial to the right or left until the desired shutter speed number click-stops and is aligned with the shutter speed index ® . The dial has indications for B (bulb) and for shutter speeds from 1 to 1/4000 sec. The 250 engraved in red indicates the fastest sync speed for an electronic flash unit. On B, the shutter curtains @ remain open for as long as the shutter release button is kept depressed. 1 is for indicating one second , 2 for 1/2 sec ., 60 for 1/60 sec. and so on. One of the two adjoining numbers, excluding B is two times or 1/2 as much as the exposure amount of the other number. Note that shutter speeds between printed numbers (i.e ., intermediate speeds) cannot be used . Since you can always confirm the shutter speed number inside the viewfinder, you don 't have to see the shutter speed dial as you turn it. 18