As best as I can explain it; exposure compensation or exposure variation (EV) is a setting that changes the brightness of an image before the camera actually takes the picture. Essentially you are telling it that you would like the picture to be darker or brighter than the settings chosen by the camera originally.
Originally Posted by DeboraBremner
In terms of photography light is measured in terms of the 'stop'. This is where you can start playing around with a lot of settings! For example, moving your aperture down one f-stop from F5.6 to F4 will double the amount of light that can enter the camera, which it turn, will double your shutter speed. This will also decrease the depth of field of an image. Higher F-stop equals more depth of field.
The distance from the subject matter will also drastically affect the depth of field.
EV is usually represented by a +- symbol.
Let's say that you want the image to be 1 stop of light darker... you would set the EV to -1.00 and this would double the shutter speed (if all else remained constant).
There are several advantages to using this method when photographing fish:
1) Fish are usually quite reflective so the light shining down on them from the tank lights will look good to you but horrible to the camera. Stepping down the EV will produce a more natural look with regards to the fish's colours.
2) Fish will usually fall under the highlights category and by stepping down the EV the fish will be better exposed and less emphasis will be placed on the surrounding features.
3) Stepping down the EV will increase the shutter speed. Yes, this will make the picture darker but that can always be changed in even the most basic editing program.
Photography is always a compromise with settings since they are all interlinked.
I hope this helps. Feel free to ask me anything else :)
Last edited by Richard Peche; 01-07-2014 at 04:44 PM.
Learning as I go... and thanking everyone on this forum for their help, advice and patience!