Thursday, June 16, 2011

Nikon AF-S 50mm F1.8G: Day 3

In yesterday's post I mentioned that vignetting seems to be more apparent in the new 50mm F1.8G, when compared to the old AF-D. I have not done a direct comparison yet, but today I'm going to post some sample images that show the effect of vignetting. These samples also give us a chance to see the differences in bokeh at different apertures. Note that these samples are coming from a FX camera (D700), and the effects of vignetting are reduced on a crop sensor (DX) camera.

Sample 1: F1.8

Although these images have been corrected in post, I did not add any vignetting reduction, for obvious reasons.

Sample 2: F2.8

I shot both of these images seconds apart, in bright light, to demonstrate the what I'm talking about. Looking at these two images you can quickly see the effect of vignetting with the 50mm F1.8G. In sample shot #1 a large portion of the frame is darkened by the vignetting, but that can be corrected by almost all post processing software. The good news is that vignetting is vastly reduced, by stopping down to F2.8, as seen in sample #2. 

Next up are two more samples, this time F1.8 vs F4.

Sample 3: F1.8

Sample 4: F4

As in the comparison between the first two samples, these two images were taken a very short time apart in the same light. You can easily see that there is more detail in the shadows at F4, thanks to the reduction of vignetting by stopping down the aperture. 

This kind of vignetting is not unexpected in a fast aperture lens, although some might consider the amount of vignetting to be an issue. For me, vignetting is not a serious issue, as it can be easily corrected while post processing images. Nikon's FX cameras also have automatic vignetting reduction settings for those who shoot jpegs.