RMNP, CO
I sometimes feel like a broken record talking about the new Nikon Z mount lenses. Everyone I have reviewed has been fantastic to unbelievable in acuity, especially on the edges and corners. Gotta appreciate that new design that allows improved sharpness in these lenses. When it comes to teleconverters, one rule holds true. A teleconverter is only as good as the glass it is attached too. Put a teleconverter on an average lens, and you get average results. Put a teleconverter on the new Nikon Z 70-200mm F2.8 S lens, being touted as the sharpest 70-200mm out there, and you get…yep, you guessed it, incredible performance.
As a rule of thumb, I don’t use telecoverters on zoom lenses, there is just too much glass in that equation for me. But I regularly attach my TC 1.4x to my 300mm F4 and 600mm F4 with very sharp results. Times are changing, however, and new lenses are just so sharp that using a converter gives great results. Look at Nikon’s 180-400mm F4 with built in 1.4x or using a converter on the brand new 120-300mm F2.8 and getting sharpness that rivals the 300mm F2.8 prime lens…wow!
Simply put, using the 1.4x on the new Z 70-200mm F2.8 and you aren’t going to notice a difference. I did a side by side comparison with the D850 300mm F4 and the Z7 70-200mm F2.8 with converter and shot them at 300mm and 280mm (200mm with 1.4x). And honestly they were both tack sharp; that is saying something for the 1.4x plus 70-200mm F2.8 since the 300mm F4 PF is a very sharp prime lens. I might even say that the corners were better on the Z lens plus 1.4x converter, pretty incredible performance. But rather than compare sharpness photographing a gritty brick wall, I went to Rocky Mnt NP to photograph elk.
RMNP, CO
Sharpness was as expected, excellent. I tried shooting at different focal lengths as well, not use maxed out at 280 each time. All the images looked great. Autofocus performance didn’t seem to be affected much either. My biggest hesitation was attaching/detaching the converter in the field. The wind was blowing dust everywhere, and the sensor on the Z series if very close to the front of the camera, so you have to be careful. But that same aspect is why the Z series lenses are so sharp on the edges and corners.,
Right now the only lens you can use this converter with is the 70-200mm F2.8. There is no super telephoto prime lens on the Z lens roadmap, but if ones becomes available, this converter will render incredible results.