I am currently in the process of testing the Nikkor 400mm f/2.8E FL lens in my Imatest lab and I am simultaneously also measuring the performance of the new Nikon TC-14E III teleconverter and comparing it to the older TC-14E II. Although I am planning to review the teleconverter separately, I decided to give our readers a glimpse of the teleconverter performance when compared to its predecessor in terms of sharpness. To make it easy to compare differences, I converted all numbers to percentages (detailed numbers will be posted in the reviews).
I am posting information based on what lenses I have tested the teleconverter with. Since teleconverter performance varies a bit depending on the lens, I suggest you look into the benefits of using the TC-14E III over the TC-14E II depending on what lenses you are planning to use. Please note that all tests for the below lenses were tested at the longest available focal lengths. Although I have previously reported that using a 1.4x teleconverter results in approximately 5% drop in sharpness, that particular test was performed at medium distance using a 70-200mm f/2.8 lens. In subsequent tests, I found out that TC performance can actually vary quite a bit depending on lens, focal length and camera to subject distance. In the below example, the sharpness penalty of the 1.4x teleconverter is probably at its “worst case scenario”. Don’t pay much attention to the differences between the blue line and other lines – look at the green and red lines, which outline performance differences between the two teleconverters:
That’s pretty interesting data – let’s do a quick analysis.
Nikkor 400mm f/2.8E FL
It seems like the new TC-14E III does really well on new lenses. Based on my data, performance differences varied between 3-4%, which might be worth looking into for those that want ultimate sharpness with their “E” series lenses. Based on how well it worked on the 400mm f/2.8E FL, I would assume we would see similar performance improvements on the 800mm f/5.6E FL and any future Nikkor super telephoto lenses.
Nikkor 70-200mm f/2.8G VR II
The performance in sharpness between the new TC-14E III and TC-14E II is practically non-existent. Looking at Imatest numbers, the difference stays very close at 1% mark, which is within the margin of error. Not worth moving up to in my opinion.
Nikkor 300mm f/4D AF-S
Now this one is interesting, because technically the TC-14E III does not work on the 300mm f/4D AF-S. When you mount the TC, the camera shows two “EE”s, indicating an error. If you look at this teleconverter compatibility chart, it clearly states that the 300mm f/4D is “not compatible”. To get the TC to work, I set aperture on the lens to f/4 and changed camera options to set aperture on the lens. The camera was locked at f/5.6 for aperture, so I had to move to manual mode to properly set exposure (aperture priority also works). As you can see from the result, it is less than 2% performance difference, so not much of an improvement here either, even if Nikon made the TC-14E III work with the 300mm f/4D.
Nikkor 200-400mm f/4G VR
Same result here – it seems like the TC-14E III does not do better compared to its predecessor on this lens. With less than 1.5% difference in sharpness, it practically brings no benefit.
Unlike the Nikkor TC-20E III, which was significantly better than its predecessor, it seems like the new TC-14E III teleconverter is only beneficial to use on the newest Nikon lenses for the most part. Based on my tests so far, it did very well on the new 400mm f/2.8E FL lens, but its performance was rather disappointing on older “G” type lenses like 70-200mm f/2.8 and 200-400mm f/4. As I get my hands on other super telephoto lenses, I will continue testing the TC-14E III and will update this article with additional information. If you have additional data or information on how the TC-14E III performs on your lenses, I would love to hear your feedback in the comments section below!
P.S. I don’t want to give too many spoilers for the upcoming 400mm f/2.8E FL review, but the lens sharpness is absolutely stunning. And boy, that lens is so light compared to its predecessor and other Nikkor super teles…