The viewfinder of the OM-D E-M1 is incredibly good, but with images like this one, I always have trouble framing them exactly as I want. You have to have exactly the right distance from your subject, the sensor plane must be exactly parallel to the window, the center of the image must be exactly in the center of the cross, and of course you have to be careful to not hold the camera at an angle.
You may forgive me or not, but that’s what Photoshop is for. “Edit / Transform / Skew”, you tug at the corners and in three seconds everything is nicely aligned. Peace of mind – I love it 😀