Does overexposing help get a better RAw file in the OMd?

Yes, this is precisely the point. What's important to to pick a good set of camera settings that can survive experimentation with proper evaluation. What you learn from this will serve you well in the field. The camera's indicators are not at all perfect, but you can readily learn how to interpret them and their idiosyncrasies and adapt on the fly to achieve consistent results.

RawDigger aids this process immensely because it provides a means for evaluation that gives straight, true goods. Trying to establish indicator interpretations without such stable and solid information is forever trying to hit a moving and poorly visible target.

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gollywop