Our latest test scene is designed to simulate both daylight and low-light shooting. Pressing the'lighting' buttons at the top of the widget allows you to switch between the two. The daylight scene is shot with manually set white balance, but the camera is left in its Auto setting for the low-light tests.
At low ISO, the E-P5's image quality is essentially identical to that of the Panasonic GX7, with a slight difference in color response (note the more punchy blues and pinks) being the main difference. The PEN does a good job of showing fine detail without the hints of moiré and over-sharpening shown by the Panasonic and Sony NEX 6.
As ISO climbs, the PEN continues to do a good job, with its JPEG engine striking a pretty good balance between noise suppression and detail retention. By comparison, the Nikon D7100 (despite its larger sensor), is starting to show signs that more noise is being left in the image, to retain additional detail. Switching to Raw mode, which has noise reduction minimized, shows that it is capturing more detail than the PEN, but the differences aren't huge. At the very highest ISO setting, the D7100's JPEG output is noticeably better but switching to Raw, the differences isn't as dramatic as you might expect. Even switching to the downsized 'Print' view, where the D7100's extra pixels should show their advantage, there's not a huge difference - meaning you should be able to get very close to the D7100's image quality if you process the files yourself.