frugivore wrote in post #18078872
If you are using your camera's auto exposure system, which it sounds like you are, then it will measure the brightness of different parts of the scene. Next, it'll figure out the average brightness of the parts it measures and set the exposure settings so that this average is about 3 stops below clipping. If your scene has a wide range between dark (fur) and light (snow) that is perhaps 7 stops of light difference, then the camera will clip the snow and you will lose all detail in it. If so, you'd need to dial in -EC to save the detail. If the difference is less, like 4 stops difference, you'd dial +-EC to maximize the sensors recording ability (ETTR).
Personally, i want to see detail in the snow, so I might set -EC. You can manually set your exposure as well to get consistency in your photos.
You seem to have managed to reverse the +/- for EC in your example. If the scene is brighter than average, the TTL metering system will make the exposure less, so that the bright white becomes dirty grey. So in this situation you would need to add some positive (+) EC. If it is really brightly lit snow, and you have a lot of it in the scene then maybe up to +2EV.
To the OP, since the exposure is being reduced because of the bright snow, that will also reduce the exposure of the darker subject too, so that can end up blocking up (the opposite to clipping). The additional exposure is given to all of the image, so that the darker colours also stay the correct brightness. Personally in a situation like this, where I don't have too much time to be chimping, I would also set Auto Exposure Bracket. I would set the AEB at +-2/3 stop, and would then set my EC to +1,1/3 stops. I would set the camera to burst mode, and in this configuration the camera will automatically shoot the the bracketed exposures around you EC offset, then stop. I also reset AEB in the custom functions menu so that it shoots -, 0, +, instead of the default 0, +, - order. That way when you are reviewing the images you see the darkest one first, and they then get progressively lighter. You should hopefully find the the + shot in the series is actually a good ETTR exposure, and if you have shot it in RAW you can then pull the highlights and midtones down in the RAW converter, while leaving the shadows unaffected. This process will allow you to bring out more details in the shadow areas, without introducing additional noise to the image. The middle exposure should then be normal. Having the three shot bracket though allows for the possibility that you got the initial guess at the correct amount of EC wrong. If you did not add enough then the + exposure becomes "normal" and you haven't really lost anything. If you overdid the initial EC, then the 0 becomes your ETTR shot, and the - is your "normal" exposure.