The exposure triangle allows us to visualize how the three main elements in photography work.
ISO- is the cameras’ sensitivity to light. ISO 100 is the base setting for most cameras and gives the cleanest image (provided conditions are suitable) as you increase ISO you add more light to your exposure but this also increases noise. Noticeable at 1600 or higher on most cameras. If your exposure is too bright at ISO 100 you would want to raise your f-stop i.e f1.8 to f2.2or raise your shutter stop i.e 1/25 to 1/50
Aperture- this controls the focus range of the exposure as well as depth of field. a wide aperture allows you to get your subject in focus and blur surrounding elements, but will also allow the most light in so you will have to adjust either ISO or shutter speed to compensate for the additional light in your exposure. A narrow f-stop will get everything in focus by allows the least amount of light in so you will have to compensate by stopping up your ISO or stopping down shutter speed.
Shutter speed- allows you to freeze or blur motion. a higher shutter speed allows less light in so you would have to increase the stop of your ISO or decrease your f-stop.
The three units work in stops so if you move a setting by one stop you can compensate by adjusting another setting by a stop (if you increase shutter speed you could either stop down your aperture or stop up your ISO). The key to getting the best results is understanding your creative intent so you can adjust the right setting. If you want everything in focus but need more light you would want to raise your ISO instead of decreasing your f-stop for example.
Jake Ten Photography 