OK. Sorry for the misunderstanding. Is your D850 still under warranty? If so I would call Nikon and see what they suggest you do. Even if it isn't I would give then a call before you try anything.

- FTn

I am a commercial photographer. If you look at my avatar that was the cover shot that I did for the Callaway Alfa Romeo Twin Turbo dealer brochure back in '84. Shot with an 8x10 Sinar view camera on Extachrome. I worked early on in my career as an assistant for Ernst Haas, David Pruitt, and Frank Poole. It was here that I learned the importance of using the sharpest lenses available.

I'm only trying to be helpful here and provide an explanation to the OP as to why his images look out of focus. If you are happy with with the image quality that you get with a with consumer grade lenses on a 45 mp good for you. The OP posted because he was not happy. Without seeing his images, my first concern is the is the Nikon 24 - 120. It may work OK with a 24 mp sensor but may not be so good with a 45 mp sensor. Nikon as well as several independent authors like Thom Hogan have published lists of the subset of Nikon lenses that will work well on the D850. The 24 - 120 mm doesn't make any of those lists.

- FTn

Sorry I didn't bother to footnote my comments about Nikon's F lenses ability to resolve but my information comes from DXOMark and and Photography Life. You may want to read "Most Nikon F Mount Lenses Cannot Resolve Adequate Detail On Modern High-Resolution Cameras" on www.photographylife.com by Nasim Mansurov. Here Mansurov presents some pretty good scientific data to back up his argument.

According to DXOMark the Nikon 24-120mm f3.5 - 5.6 only scores a 12 for sharpness and the Nikon 24-120mm f4 doesn't do much better with a score of 16. Just as a reference the 105mm F1.4 scores a 40 and the 28mm f1.8 scores a 33 but, according to Mansurov, the 28mm f1.8 doesn't have the resolving power to take full advantage of the abilities of a 45 mp sensor. I can't find the 28mm f1.4 on DXOMark yet. The bottom line here is that to take full advantage of the abilities of a 45 MP sensor like the one used in a D850 you have to buy great glass. Otherwise it's kind of like putting Mastercraft tires on a Ferrari.

- FTn

Pay particular attention to Steve's section on formal testing. I know that shooting a test chart is not the most fun but if you want really sharp pictures you need to test all of your lenses with your D850 at all apertures to find each lens' sweet spot. It is usually about 2 to 3 stops down from wide open. If you do need to send your camera and lenses back to Nikon you will need to include these files to the teck can see what it is doing.

You may also want to use the auto focus fine tuning that is available in the menus of the D850. Again you will have to do this for all of your lenses.

Unfortunately very few of Nikon's F lenses have the resolving power to work well with a 45 mp sensor. If you want to take full advantage of the D850's sensor you need to pick your lenses wisely.

- FTn

Most healthcare facilities have pretty extensive video surveillance systems both inside and outside the facilities. If you know the the young woman have her request the video recordings of that parking lot for the night it occurred. Have the the police review them if this hasn't already been done. They should come up with the identities of the persons involved.

- FTn

One more question, is this happening when the lens is mounted on a solid tripod and you are focusing on a stationary test chart?

- FTn

Busch and Hogan are both great authors and photographers. I have both of their books on the D850. Hogan's books are far more technical. He gets into into sensor construction and in depth explanations of why the older Nikkor film lenses aren't as sharp as their newer versions when used on camera bodies with sensors for example. You won't be wasting your money or time with Tom Hogan's books.

- FTn

Hi -

Need some additional information. What camera body are you using and what focus mode to you have it set on? I have an 80-400mm and find that I use spot focus most of the time with it especially if I'm using it with a 1.4x TC III.

- FTn

I have a TC 1.4 III. Really sharp and I get 15 focus points with my D850 and 80-400mm. Get a refurbed one if you can find one.

- FTn

The Nikon 105mm f1.4 is on sale for $1897. It is a wonderfully sharp short telephoto but is not a macro lens. The Nikon 105mm f2.8 Micro Nikkor is on sale for $807. Prices are from B+H. Nikon calls their close focus lenses micro lenses while the rest of the world calls them macro lenses. Don't ask me why 'cause I haven't got a clue.

- FTn

I sure miss my 105 f2.5 but unfortunately it was stolen from my dorm room many years ago. A good friend of mine (I was his studio assistant for a few years) has the 105 micro and loves it. It's really sharp corner to corner. If you are looking for the buttery bokah of the old 105 f2.5 get your hands on the new 105 f1.4. That's the closest that I have been able to come to the old 105 f2.5. Unfortunately, the 105 f1.4 won't focus anywhere near as close as the micro 105.

- FTn

It looks like photophique's basis for selection was convenience and price. The 28-300mm Nikon lens is one of softest lenses in the Nikon lineup especially above 200mm. Using it on a D850 defeats the purpose of buying a 45 megapixel camera. The Nikon 35mm f1.4 does not have the resolving power to give you the sharpest images on a D850. Only Nikon's 20mm f1.8 and 28mm f1.4 can do that. I don't know much about Tamron and Sigma lenses. I have never shot with them. I would instead go with Nikon's 24-70 f2.8, non VR, and the 105mm f2.8 Micro Nikkor. Staying with the same manufacturer for both camera bodies and lenses removes the finger pointing if you have a problem. The 200-500mm f5.6 barely exceeds 36 megapixels at 300mm f5.6 so I'm not sure that this heavy lens is a best pick for a D850. My gut tells me that the 500mm f5.6 might be a better choice but I have never had a chance to shoot with one. This is only my opinion.

- FTn

Let me start out by saying that I shoot with a D850 and love it. Keep in mind though the D850 demands very sharp lenses to really take advantage of its 45 megapixel sensor. According to Photgraphylife.com very few of Nikon's current F mount lenses can resolve adequate detail on modern high resolution cameras. Read their article Why Nikon Should Not Make DSLRs Over 36 Megapixels. I have found that the lenses that they recommend for the D850 is pretty spot on.

- FTn

You may want to read Steve Perry's ebook Secrets To The Nikon Autofocus System. There are many different focus menu settings on the D500 and Steve goes into them in detail. You also may want to check out his videos on YouTube.

- FTn

You might want to look at the fine print in your PPA policy. I believe that they will only give you market value for a claim not replacement value. Big difference.

- FTn