E-p3 jpegs are different than e-m5
You could always add a stop (+1) of exposure compensation if you want the EM-5 to shoot "brighter". It's less likely to blow the highlights as it has a higher DR overall, but adding the EC will reduce your headroom on the highlights. Not sure if Oly has an "active D-Lighting" equivalent (different manufacturers call it different things) but I imagine they do. Might be worth investigating.
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