Rachel Foster
New member
Well, I can  learn!
ISO, shutter speed, and aperture all interact to control the light that reaches the sensor when an image is captures. The faster the shutter speed, the less light. With ISO, the lower the number, the less light the camera “gets.” Aperture (how wide the opening is) also plays a role. The bigger the opening (aperture) the more light let in. An aperture of 2.8 is largest, while 16 is small. By manipulating the balance between these three things, the exposure can be varied.
A zoom lens is one that can change focal length. A telephoto is a lens with a long focal length. With a film camera, magnification (1.5)(lens/50). So, 300 on a digital camera magnifies the image by a factor of about nine.
A wide angle lens gives a “larger” view, showing “more.” The telephoto has a smaller area captured. This is because when you are closer to the object, you have less distance that can be viewed. For example, if you’re standing at the foot of a mountain you see a relatively small area. If you are a mile away, you see “more” mountain (i.e., the entire mountain although in less detail).
The speed of a lens can also affect the exposure. A “faster” lens allows a faster shutter speed without underexposing the image. This lens -- 60mm f/2.8 EF-S MACRO (USM) LENS – is a
prime lens, also called a fixed lens. The 2.8 is the speed of the lens and indicates the maximum opening possible. The bigger the opening, the more light let in…the “faster” the lens. This is because more light allows a faster shutter speed.
DOF is determined by aperture. For a sharp focal point with blurred background, use a larger aperture (say f/2.8). For a longer dof, use a small aperture (say, 16).
Just thought I’d demonstrate that I’m serious about what I’m doing . This is from memory without reference to notes.
								ISO, shutter speed, and aperture all interact to control the light that reaches the sensor when an image is captures. The faster the shutter speed, the less light. With ISO, the lower the number, the less light the camera “gets.” Aperture (how wide the opening is) also plays a role. The bigger the opening (aperture) the more light let in. An aperture of 2.8 is largest, while 16 is small. By manipulating the balance between these three things, the exposure can be varied.
A zoom lens is one that can change focal length. A telephoto is a lens with a long focal length. With a film camera, magnification (1.5)(lens/50). So, 300 on a digital camera magnifies the image by a factor of about nine.
A wide angle lens gives a “larger” view, showing “more.” The telephoto has a smaller area captured. This is because when you are closer to the object, you have less distance that can be viewed. For example, if you’re standing at the foot of a mountain you see a relatively small area. If you are a mile away, you see “more” mountain (i.e., the entire mountain although in less detail).
The speed of a lens can also affect the exposure. A “faster” lens allows a faster shutter speed without underexposing the image. This lens -- 60mm f/2.8 EF-S MACRO (USM) LENS – is a
prime lens, also called a fixed lens. The 2.8 is the speed of the lens and indicates the maximum opening possible. The bigger the opening, the more light let in…the “faster” the lens. This is because more light allows a faster shutter speed.
DOF is determined by aperture. For a sharp focal point with blurred background, use a larger aperture (say f/2.8). For a longer dof, use a small aperture (say, 16).
Just thought I’d demonstrate that I’m serious about what I’m doing . This is from memory without reference to notes.
