To keep the generic "do I upgrade?" questions from proliferating in my In box now that the Z6 III has appeared, here are my current thoughts, in somewhat concise form (subject to verification using a production camera, which I should have in a couple of days):
- D6xx/D750 user — Yes. There's now a mirrorless camera that pretty much pushes everything you have well forward except for perhaps basic image quality (24mp full frame has been relatively stable for a decade in image quality, though you do get better raw bit depth, small files, and new Picture Controls).
- D8xx user — No. If the Z8 didn't already entice you, the Z6 III likely won't (or you had the wrong camera in the first place). The Z8 is still the most appropriate mirrorless camera for a D8xx user.
- Z5/Z6 user — Yes (but consider also the Zf). The Z9 generation of cameras offers more performance and more features, all of that quite useful. You now have two choices that offer that (Z6 III and Zf).
- Z6 II user — Probably. I generally recommend waiting two generations to upgrade, but the Z6 III is a pretty substantial upgrade over what you have. Plus you waited about the same amount of time as two generations ;~).
- Z7/Z7 II user — No. This is a tricky one. If you were using your Z7 model mostly for landscapes or architecture on a tripod, the pixel-shift of the Zf and Z6 III give you more (96mp) and better pixels to work with and the answer might be Yes. However, for everyone else there is now a product space between the Z6 III and Z8 that needs updating, and I believe Nikon will eventually address it, so you wait.
- Df user — No. The Zf is the proper camera for you. Yes if you got tired of retro dials and glued together UX.
Why no advice for the D# pro DSLR body or consumer DX DSLR owners?
The D# pro DSLR body owner should first consider the Z9, and then contemplate whether a Z8 works for them. Moving down to the Z6 III body loses a great deal (battery life, customization, etc.).
The DX DSLR owners have a lot of things they need to answer before they can consider upgrading at all. Nikon's Z DX lineup is very bottom-targeted and limited, all of which means potential weight and price penalties when you start considering FX bodies to replace your older DX DSLR.
Of course GAS (gear acquisition syndrome) says Yes and your credit card says No. Your significant other might want to give their advice, so consult them (i.e. happy spouse, happy house). The Internet fora will say both Yes and No, very loudly and at the same time. Nikon is shouting Please Yes. I'll let you resolve all these answer discrepancies on your own ;~).
