I remembered reading a review about 8-10 years ago comparing the Nikon 17-35mm f/2.8 to Nikon primes in a similar range and the verdict was plain--the zoom was better. However, I remembered that the only real characteristic that defined this was with respect to chromatic aberration. And with Nikon's new software CA removal as standard in it's cameras I thought that revisiting the performance of the 20mm f/2.8 (sans CA) was worthwhile.
Now whilst I don't have FF figures for a 17-35mm f/2.8 for comparison from Photozone I was able to review the DXOMark scores comparing the Nikon 17-35mm f/2.8 against the Nikon 16-35mm f/4 and it was clear that the 16-35mm f/4 was better. So, when reviewing MTF scores I restricted myself to reviewing only Nikon's 20mm f/2.8, 14-24mm f/2.8 and 16-35mm f/4 as depicted in the graph below.
Data courtesy of Photozone.de
Now, don't get me wrong, it's not my intention to suggest that one lens here is any better than the other MTF wise as variations in individual lenses can vary widely. What I am trying to demonstrate is that as far as MTF goes between the above three lenses at 20mm and at f/8 is that there is not a lot to separate them. So, if you think that by buying the 20mm f/2.8 that you are somehow losing out in the resolution stakes against it's bigger and newer brothers then don't. It may be an older and smaller lens but it holds it's own with the best of them and at 1/3rd the price of the 14-24mm f/2.8 and half the price of the 16-35mm f/4 it should factor heavily in your consideration for an inexpensive high-performing ultra-wide angle lens.





