I have used and sold on TC14 II, after I read a couple of recommendations the current model ie TC14 III is designed for the E Nikkors. Nikon released it with the 400 f2.8E FL...
Anyway, somewhat on the 'Concorde Principle' I bought a new vIII after investing heavily in E telephotos in 2018. My experience is vIII works very well with the 300 PF ie 420 f5.6 and 500 PF ie 700 f8. Also 70-200 f2.8E FL and 400 f2.8E. So well I added a backup TC14 III that became available Used. (I will organize some example images.)
It is critical to AF tune each combo on your DSLR(s). I have used the above combos on D500, D780, and Z7, and currently D5 with D850. Obviously AF takes a hit on the 500 PF at f8 on a DSLR. This article is a usful overview, and the PL reviews of telephoto usually include tests and examples with relevant teleconverters
Wondering about what a teleconverter is and how you can use it? In this article, we go through everything you need to know about using teleconverters.
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