First way to control light into the camera:The slower the shutter speed more light hits the film.
Second way is through the aperture:The smaller the aperture the less light.
1 sec slow
1/30 sec
1/1000 sec fast
Lower num=small aperture.
Higher num=larger aperture
shutter aperture really dark1/125 f/11shutter aperture really light1/30 f/5.6shutter aperture very dark 1/125 f/22shutter aperture very bright 1/4 f/2.8shutter aperture good normal1/30 f/8Depth of field (DOF)................Background(DOF)ForgroundThe smaller the aperture the less light depth of field
The larger the aperture the more light but small depth of field