keywest305 wrote:
So I purchased the Nikon Z9 about 4 weeks ago. I did it for the silent shutter and eye detection for people and animals. Yes this works to my satisfaction. The image quality is the same as my D850 I would say. I sold 15 or 16 of my lens to scale down but with hard choice kept my Tamron 15-30 24-70 70-200 all in G2 series. Also kept my Nikon 200-500 and for portrait the Nikon 105 1.4e oh and the nifty 50 1.8. My dilemma is I read articles where people say you must use Z lenses to get full quality out of the camera. So I think about selling these lenses. Today since it was nice out I took these lenses outside and tested each one on the camera and ( yes it came with a free ftz2 adapter ) they all were spot on with quick AF and picked up my dogs eye immediately as he ran around the yard. I also bought the Z 24-70s and the f mounts were just as quick in my opinion. So I'm torn whether it's worth the sale of the Fmount to go Zmount. If Z is quicker to focus its milliseconds I would say.
So I purchased the Nikon Z9 about 4 weeks ago. I d... (
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You do not 'need' to sell your F-mount lenses and get Z mount lenses. The FTZ works very well and the Z9 drives the F Mount lenses via FTZ even better than does the Z6/7II's so it is now very nearly native in speed.
I shoot with both F mount and Z mount lenses, and I used to have the Tamron G2 versions of the 24-70 and the 70-200 - I have subsequently sold both, and bought the S line Nikkor Z versions of them, which are better, but that said the Tamrn G2's are very, very good and unless you are a professional getting paid (as I am), or just a strict perfectionist with a massive budget, I do not see a need for you to replace these lenses at this time - maybe in the future if they ever break or need serious repair then replace them.
As for the 105 1.4 E lens for F mount, I still use this lens to this day and do not have plans to get rid of it - it works exceptionally well via FTZ - better I would say than on a DSLR as it now enjoys 3 axis image stabilization as well as focusing points across the frame.
In short, if you are happy with the image quality (IQ) of the F mount lenses, they will be as good as they ever were via the FTZ and the focusing speed and acquisition (especially using a Z9 body) with FTZ will be near native - on Z9 it is arguably as fast as the Z mount lenses and if not it is so close that it really does not matter.
This all said, there is a difference in IQ between the F mount and Z mount lenses with the Z mount lenses generally being sharper out to the corners of the frame as well as being sharper at wider/wide open apertures.
Thus, if you are a landscape photographer, you may have a use case to get Z S line lenses for your landscapes especially if you are going to make big enlargements.
As a portrait photographer, edge sharpness matters a lot less. That said, I do have and love the 50mm 1.2 S line lens and also will be getting the 85 1.2 S line lens, but plan to keep the 105 1.4 E lens and continue using it as well, so a lot of the decision comes down to your individual use case - but I would not sweat the AF performance using F mount lenses on the FTZ - especially with the Z9.
Hope this helps :)
-B