Sigma C21EN0291 User Manual

After you set the aperture value you desire, the camera will determine the 
appropriate shutter speed. If you select smaller apertures, depth of field will be 
greater. The larger apertures tend to blur the background, as depth of field will 
be shallower. 

 

1 

Set the “D”-Dial to “Drive–Area” (P.14). 

2 

Set the “Mode” –Selector to A position 

3 

Press the shutter button “Half-Way” to verify 
the focus, and select the desired aperture 
value by turning the “C” –Dial. 

4 

Verify the setting in the viewfinder. 

 
 

 
 
 
If the appropriate shutter speed is out of the 
range of suitable combinations due to the 
subject being too bright or too dark, the 
shutter speed indicator will blink. If the 
subject is too bright, set the aperture value 
to a smaller one (larger F-number), or if the 
subject is too dark, set the aperture value to 
a larger one (smaller F-number) until the 
indicator stops blinking. 

 
 

· 

The range of available slow shutter speeds varies depending on the ISO setting 

(P.52). At ISO 100, shutters speeds up to 15 sec. can be used. At ISO 200 and 
400, shutter speeds up to 1 sec. can be used.