How do f-stops affect picture quality?

Answer 1

Through exposure. If your outside shooting on hot sunny day your picture might be over-exposed if you shoot an image with an f-stop/aperture of a about f/2-f/4. You can change your f-stop to about f/32 for less light to enter through the lens and to decrease light. Shutter speed also has a major part of exposure. A shutter speed of about 1/8 will let in a lot of light. A higher shutter speed of about 1/500 would let in a lot less light.

Answer:Aperture can affect the quality of a photographic image in at least four ways.

First, and most well known, as the aperture (the lens opening -- the hole through which the picture enters the camera) gets larger it lets in more light and you can take a picture in darker locations, or you can take pictures at higher shutter speeds thus freezing movement better.

The next most commonly known effect is that the wider the aperture the shallower the depth of field. That is, the fewer things in front of or behind the subject of the picture are in focus. As the aperture gets smaller things further away from the subject in both directions are clear.

Another way aperture can affect the image is that your lens will be sharpest at some aperture. Often somewhere around F5.6 to F8 your lens will make the sharpest (clearest) images. This is called "the sweet spot."

Finally, for technical reasons, at very small apertures (usually F16, f22 or smaller) an optical phenomenon caller diffraction causes the image to become become less sharp. You can think of it that when light must squeeze through a tiny hole the light rays interfere with each other.

Answer 2

The smaller the size of the lens opening (the larger the f-number) the greater the depth of field. But the small apertur will mean a slowe shutter speed which might result in blurring due to camera shake.