Full review link
All of the following is taken from Robin Wong’s Article linked above.
“To carry out my shooting test on the field, I used the OM-D E-M10 for this blog entry. I tried to shoot a wide range of subjects, including environmental portraits, headshot portraits, close-up shooting of various subjects including food, as well as a bit of tight landscape. Whenever possible I did my best to highlight the shallow depth of field rendering of the open wide F1.8 aperture. On the other hand, I also explored shooting with various aperture opening, stopping down to gain maximum depth of field. So how does the M.Zuiko 25mm F1.8 lens perform, in terms of image quality (sharpness, technical control of distortion and chromatic aberration), autofocus performance, and how does the lens handle with the new OM-D E-M10?
LENS SHARPNESS AND CONTRAST
The new Olympus M.Zuiko 25mm F1.8 lens is VERY sharp. When I was reviewing the images, the sharpness of the lens reminded me of the M.Zuiko 45mm F1.8. Although I did not do side by side comparison, I can safely testify that the sharpness level of the 25mm F1.8 is on par with 45mm F1.8 (if not slightly better than the 45mm!), very capable of resolving fine detail, and the sharpness is very even all across the frame. As usual, not a surprise coming from Olympus, the great sharpness can be achieved even shooting at F1.8 wide open with the 25mm F1.8 lens, and stopping down will improve the sharpness surely but not that significantly noticeable to me.
There is something interesting about the contrast rendering of this M.Zuiko 25mm F1.8 lens. It does seem like the images come out more punchy with higher contrast. This was especially noticeable when I switched lens immediately from the M.Zuiko 14-42mm F2.5-5.6 EZ Pancake Zoom lens. In fact the only time I remember seeing this kind of contrast level was when I was shooting with the Olympus M.Zuiko 75mm F1.8 lens. I admit that the 25mm F1.8 is not as sharp as the 75mm F1.8 (one of the sharpest lenses around in the market) but the look and feel of the images somehow came out with similar tones. This is the main reason, straight out of the camera, images from the 25mm F1.8 actually looks a tad bit better than the 45mm F1.8.”