Aperture: T he opening of a lens's diaphragm where light passes. Lower f/stops give more exposure because they represent the larger apertures , while the higher f/stops give less exposure because they represent smaller apertures. https://www.nikonusa.com/en/learn-and-explore/a/tips-and-techniques/understanding-maximum-aperture.html Shutter Speed: A measurement of the time the shutter is open, shown in seconds or fractions of a second. The faster the shutter speed the easier it is to photograph the subject without blur and “freeze” motion and the smaller the effects of camera shake. https://imaging.nikon.com/lineup/dslr/basics/04/03.htm ISO: It refers to the image sensor's sensitivity to light. The lower the number, the less sensitive the image sensor is to light. Most photographers will have to lower their shutter speeds, aperture and raise their ISO . https://wp-modula.com/what-is-iso...