By Luke Heyfield
Many camera kits come with a 18-55mm zoom lens, which is a versatile lens under common shooting conditions. But if you want to take portraits with nice bokeh, or shoot in low-light conditions, these kit lenses usually aren’t optimal. Most of these lenses have a maximum aperture of f-4/5.6 (depending on the focal length you’re shooting at) and it can be a bit tough to achieve these effects with that aperture.
Many photographers swear by an f-1.8, 50mm lens. Some even say this is their main shooting lens and they barely use other lenses.
We’ve all been out in great locations, taking what we thought were perfect shots, only to discover that the scene has turned out really bright and washed out. Or we got the family perfectly posed, only to discover everyone in the photo is dark and their features are hidden.
What went wrong?
These mishaps happen because the automatic exposure sensor in your camera can get fooled by certain lighting conditions.
If you take a picture and there is a bright light source BEHIND the subject you want to take a picture of, that light source will send too much light into the camera.
The camera has to rely the amount of light coming through the lens and falling on the sensor,so sometimes it gets it wrong. Because the sensor tries to average the exposure out while not losing any of the bright areas in the photo, it can end up exposing for the light source instead of the subject.
So when could that happen?
It could happen:
a)If you take a photograph with the sun in front of you instead of behind you, (a sunset, or a group shot on holiday, for example)