Somebody please explain! Why X-E1 JPEGS are darker?

Every camera maker tweaks their cameras differently. There are always variations in metering, exposure, color, white balance etc. It is not only differences between the camera makers, but differences between cameras within a line of cameras. There may be variations between a Canon 550D and a Canon 7D. None of this is a big deal. That is why we have exposure compensation, in camera adjustments of white balance, color etc. Most importantly, this is why we have post processing. If you have images that you perceive as to dark, just lighten them up (levels is the best way, because using center slider primarily lightens the dark areas).

Personally, I prefer slightly darker images. I am less likely to have blown highlights and more likely to recover information.

If you want your XE1 to capture lighter images in camera, experiment and start increasing the by 1/3 increments, until you are happy.

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