Park Bench -- NEX-5N & EL-Nikkor 63mm f3.5 enlarging lens. Click for larger.
One interesting thing about the lens, like some other enlarging lenses, is that at wide open, the aperture blades are not hidden, like a normal lens does. So, this lens probably has a maximum aperture of f2.8 when completely open. The later version of this lens actually was rated at f2.8, at about the same size. Quite possibly at f2.8, the image quality was not up to Nikon's standards, hence the stopped-down maximum aperture. The picture below was shot at f3.5, but you can see the octagonal shape in the out of focus area:
Bokeh at f3.5 -- NEX-5N & EL-Nikkor 63mm f3.5. click for larger.
The image quality is by no means bad. It's actually very sharp at close range. Just not as good at infinity. It does not have the micro contrast as the EL-Nikkor 50mm f2.8, possibly due to the coating (or lack of multiple coating) on the 63mm f3.5. But, the built quality is fantastic with all metal lens barrel and mount.
Fall Leaves -- NEX-5N & EL-Nikkor 63mm f3.5.
This lens is believed to be able to produce pictures in the UV region. I don't know if this is true or not. Not that I care much as I don't have a UV capable camera.
Overall, it's a nice little lens which complements the EL-Nikkor 50mm f2.8 nicely.