4) Lens Sharpness and Contrast
Both samples of the Nikon 24mm f/1.8G produced stellar results when measuring the MTF performance of the lens using Imatest. One of the samples had a slight de-centering issue on the top left corner of the frame, but it was not bad and something to be expected from most lenses out there, including pro-grade lenses. Below is the MTF result from the better sample:
When I first saw some sample numbers from Imatest, I found the numbers a bit hard to believe, since such sharpness is usually not something I had previously seen on cheaper wide-angle prime lenses. As you can see, the lens is quite sharp wide open and it reaches phenomenal levels of sharpness already at f/2.8 and peaks out at f/4, where it truly shines. In fact, as you will see from the next section of this review, the 24mm f/1.8G outperforms the 24mm f/1.4G in center frame resolution and produces impressive results in the extreme corners as well, especially when stopped down. Color and contrast are both excellent as well.
Unlike telephoto lenses, wide-angle lenses are not designed to yield beautiful bokeh. When shooting with the 24mm f/1.8G, you can get pretty decent results at large apertures, as long as your subject is near the minimum focus distance. Below are a couple of examples that show the subject separation and bokeh capabilities oft the lens:
As expected from most wide angle lenses, the Nikkor 24mm f/1.8G shows a pretty significant level of vignetting at maximum aperture. The good news is, vignetting is drastically decreased as you stop down. The bad news is that if you decide to use a standard width polarizing filter, you might end up with darker corners. Below is the summary of vignetting levels produced by the 24mm f/1.8G at both close focus and infinity:
And here is an extreme example of vignetting at f/1.8:
The vignetting issues can be quickly corrected in Adobe Photoshop or Lightroom, so it is not a big problem. Both ACR and Lightroom already have built-in lens profiles for the Nikkor 24mm f/1.8G.
7) Ghosting and Flare
As we have previously demonstrated in a number of articles and reviews, the use of Nano-coated glass helps a great deal in reducing ghosting and flare in images. Despite being an enthusiast-grade lens, the Nikon 24mm f/1.8G has Nano coating applied to its glass elements. As a result, and as can be seen from the sample images provided in this review, the lens does a superb job when shooting with the sun in the frame.
Here is what we can expect when the sun is placed on the side of the frame:
If you look at the bush on the right side of the frame, you will notice some traces of ghosting flare on it. This is very normal and something you will see on pretty much any other lens.
Here is another situation with the sun a bit closer to the center of the frame:
The lens handled this situation wonderfully. Although there were a couple of flares on the lower side of the frame, I was able to quickly take care of them in Lightroom using the spot healing tool.
And lastly, don’t forget that you can always utilize the “finger the sun technique” to completely get rid of any traces of ghosting and flare. The below image was shot using this particular technique:
Just like the Nikon 24mm f/1.4G, the 24mm f/1.8G exhibits some barrel distortion, which can get stronger or weaker depending on how close your subject is. Basically, the closer you focus, the more barrel distortion you will see. Imatest measured roughly 1.02% barrel distortion at a rough distance of 5 feet, which is pretty much identical to what the 24mm f/1.4G produces (approximately 1.05%). It is really nothing to worry about and the problem can be easily fixed in Photoshop using the Lens Correction Filter.
9) Chromatic Aberration
Let’s take a look at how the lens controls lateral chromatic aberration when compared to other 24mm primes:
As you can see, the Nikon 24mm f/1.8G shows very low levels of lateral chromatic aberration when compared to other primes. At less than a pixel, it outperforms and all other 24mm primes! Interestingly, the most expensive 24mm f/1.4G shows the highest levels of CA.
10) Infrared Performance
With a lens design that incorporates two aspherical lens elements, I wondered how the Nikon 24mm f/1.8G would perform on an infrared-converted camera. To my surprise, the lens did quite well, showing little signs of hot spots. Here is an extremely exaggerated example of an image that was converted to B&W, then adjusted to +100 Clarity and -33 Contrast in Lightroom:
The image was shot at infinity focus and with an aperture of f/8. As you can see, there is a little bit of a hot spot area in the center, but it probably won’t be seen in your images.
11) Coma / Astrophotography Performance
Since the lens has quite good wide sharpness performance at large apertures, one might wonder if it would be a good candidate for astrophotography. As can be seen from the below image shot at f/2, the lens sadly does not deal with coma very well, making the stars appear like butterflies towards the edges of the frame:
This is quite normal behavior for such a lens – very few lenses out there are able to handle coma well in the corners.
Let’s now move on lens comparisons.