Arsat 50/1.4 - First Impression

I recently bought an Arsat H 50/1.4 lens for my Nikon DSLR. It is a cheap lens (<100$), however it is not really easy to find. Some items can be catched on ebay.

This lens is a soviet copy of the Nikon 50/1.4 standart AI-S lens. The build quality of the lens is not comparable to high quality Nikon lenses. Anyway, the lens is fully made of metal and it feels like a solid rock. the zoom ring is smooth but the aperture ring seems a bit fragile. The engravings indicating the aperture and the focus distance are dumpy. The rubber band of the focus ring is a piece of crap : it is poorly assembled to the focus ring.

At wide open aperture, the lens suffers from excessive chromatic abberations when using it in normal field condition thus resulting in dreamy pictures, especially when using it focused at the infinite. The image below is a 1:1 crop of a shoot at 1.4 focused on infinite :


Stopping down to 2.8 helps a lot :


I've not done strict resolution tests, nonetheless, the center performance seems to be very good from 2.8 to 16, but border performance is only good from 5.6 aperture. At wide open aperture, the border resolution is awful, and the center resolution is not so good : the lens seems to suffers of high diffraction/reflexion in it (as shown in the above image), using it in low contrast and low light condition helps here.

Even if this lens is far for perfect, it is still a very funny lens to use and some good pictures may be produced with it. Here are some sample pictures that demonstrates that a reasonnable level of sharpness can be reached with it :



Above pictures have been taken with aperture of 1.4 & 2.8.