Derrel
Mr. Rain Cloud
- Joined
- Jul 23, 2009
- Messages
- 48,225
- Reaction score
- 18,941
- Location
- USA
- Website
- www.pbase.com
- Can others edit my Photos
- Photos OK to edit
Exposure compensation is a fast and easy way to compensate for strong backlighting or other instances of lighting that's fooling the light metering system, or where the desired exposure needs to be significantly altered from what the meter reading is giving. In strong backlighting, with a person seen against say the late afternoon sunlight hitting a wide expanse of open ocean or lake, with shorter focal length lenses, some Plus EC is often helpful, say +2.5 EV for example. If the lens has a very tight, telephoto angle of view, the degree of needed EC is often going to be much less than with a wide-angle lens. A 300mm lens from say 15 feet away acts almost like a semi-spot meter when aimed at a person's face, and the metered exposure might very likely deliver a good, solid exposure. However, if you stand in the same place and point the camera at the person with all that backlighting over open water, and the lens is a 28mm lens from 15 feet...there's a huge chance that you'd be wise to ADD some more exposure to the metered reading....like +2.0 or + 2.3, or even plus 2.5 EV, or maybe even plus 3.0 EV.
The degree of exposure compensation needed varies quite a bit with the lens angle of view, and with individual scene types. The wider the lens angle of view, or the more extreme the situation is, the more chance there will be a need for a substantial amount of EC to get the metered reading to produce the desired result in terms of final exposure settings.
A good example is a speaker who is spot-lighted, standing at a podium, and behind is a dark, deep blue or red velvet stage curtain...or behind is a dim, PowerPoint presentation image...in this case, the light meter will tend to grossly OVER-expose the subject, and this is when dialing in maybe Minus 3.0 EV or so is about the right starting point from a center-weighted meter's baseline reading. Again, with a 50mm lens, you might need Minus 5.0 EV; with a 135mm lens, maybe Minus 3.0 EV; with a 400mm, you might only need Minus 0.7 EV. Again...what the meter "sees" and what the subject "is" varies, scene by scene.
With a digital camera, it's easy to shoot a shot using the light meter as your guide, then review the image, and add or subtract Exposure COmpensation as-needed, to get the results you want, with the meter "centered" in Manual, or in Aperture, SHutter, or Programmed automatic modes.
The degree of exposure compensation needed varies quite a bit with the lens angle of view, and with individual scene types. The wider the lens angle of view, or the more extreme the situation is, the more chance there will be a need for a substantial amount of EC to get the metered reading to produce the desired result in terms of final exposure settings.
A good example is a speaker who is spot-lighted, standing at a podium, and behind is a dark, deep blue or red velvet stage curtain...or behind is a dim, PowerPoint presentation image...in this case, the light meter will tend to grossly OVER-expose the subject, and this is when dialing in maybe Minus 3.0 EV or so is about the right starting point from a center-weighted meter's baseline reading. Again, with a 50mm lens, you might need Minus 5.0 EV; with a 135mm lens, maybe Minus 3.0 EV; with a 400mm, you might only need Minus 0.7 EV. Again...what the meter "sees" and what the subject "is" varies, scene by scene.
With a digital camera, it's easy to shoot a shot using the light meter as your guide, then review the image, and add or subtract Exposure COmpensation as-needed, to get the results you want, with the meter "centered" in Manual, or in Aperture, SHutter, or Programmed automatic modes.