Nikon1201

Nikon D610. It is much lighter ,full frame and a great camera to hand hold those big lenses.

CO

I think the Z6 I rented probably did not have the firmware update. I'm not sure if that's shown in the metadata of the images. If so, I could go back and look at the images I took to see which firmware version the camera had.

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

To match up your only choice is the Z7. Make sure it has the new eye AF firmware installed, or, if it does not you can install it.
The knock on the Z7 is that it does not focus as well as your current camera. I am not sure the firmware will fix the problem.
I love Nikon and have shot them for over 50 years. But, personally, I believe they rushed the Z's.
If it were me I would either wait for the next generation of Z or buy another D850. My opinion.

ELNikkor

If you don't like adapters, don't get a Z6 or Z7. Sounds like you either need the D750, or a D500. Either can be had for around $1500. I would lean toward the D500 as it has a lot in common with the D850 and would seem to extend the lenses. The D750 does have a built-in flash, which comes in handy now'n then...

RahulKhosla

Very sensible suggestion thanks. Will wait !

digit-up Loc: Flushing, Michigan

With a simple adapter, you might consider one of the “Very-good Fuji mirrorless cameras, and use your lenses. I have two fuji mirrorless models, & it seems that MANY are raving about fuji. RJM

charlienow Loc: Hershey, PA

why not just buy another 850...no learning curve...not much heavier...

cambriaman Loc: Central CA Coast

I second this advice. I must say I was composing, mentally, almost precisely what quixdraw has just posted when I read that post.

dick ranez

My first choice would be a second 850. If budget limits, my second choice would be an 810 the a 610.

larryepage Loc: North Texas area

The D850 is a good value. If the idea of having a DX camera as your second, you'll find that the D500 is operationally and photographically nearly identical to your D850. There will be no thought or delay involved in moving from one to the other. Pixel density is almost identical, so the optimum lenses are the same for both cameras.

markstjohn

I was in the same boat. I decided to get the D500 which will be my long distance and wildlife camera. It is small and the crop helps with the long distance shots.

amfoto1 Loc: San Jose, Calif. USA

I used to feel that way too.... But then I got to thinking about it and saw the clever adapters Canon came up with for their EOS R and RF, which gave me second thoughts.

A couple years ago, when Canon was first tinkering with the idea of a mirrorless full frame camera, they sent out a questionnaire to current system users and I responded that I'd much prefer a camera that could directly use their EF lenses, without need for an adapter. There's little size/weight savings to be had with a full frame mirrorless anyway, so why not just use the same lens register. If anything, I suggested providing a camera with a removable lens mount to allow future lenses with short register to be used on it.... Then I realized that's exactly what a well designed adapter does! D'oh!

Canon offers several different EF to RF adapters. One is a plain adapter.... no optics and just straight pass-through of the electronic communication between camera and lens. The second has an added "control ring" that can be programmed to provide different functions (many of the new RF lenses also have this ring). It's up to the photographer how they want to use that ring. It can change the focus mode, switch the camera from RAW to JPEG, provide an "instant return" to a pre-focused point, change ISO or any number of other things.

There are currently two different versions of Canon's third adapter, which has a slot in the side to accommodate a drop-in filter. One version comes with a circular polarizer, while the other has a variable ND filter. It also should have option to use a plain filter holder that can accommodate various other types of filters in 52mm size, but we have yet to see Canon offer this either as a version or as an accessory to these versions. The filter holder type of adapter will be especially useful with certain lenses, such as the 8-15mm or 15mm Fisheye lenses, the TS-E "Tilt Shift" lenses (especially the 17mm), or the 11-24mm zoom. Those have convex front elements that make it difficult to use filters with them, which might be solved using one of these adapters.

Users report no problems with autofocus performance of adapted Canon EF lenses on the R-series cameras. They are as fast as ever. Maybe even better than on some of the DSLRs. And the R-series have exceptionally low light focusing capabilities. The R can still autofocus in three full stops lower light than the most capable Canon DSLR. The R can still focus as low as -6EV (approx. "starlight"), while the very best any of the DSLRs can do is -3EV (approx. "moonlight"). If I recall correctly, the less expensive RF is rated to focus two stops lower, to -5EV.

Lens adapters are simply going to be a fact of life for anyone wanting to use a mirrorless camera from Canon or Nikon, for the foreseeable future. It's going to be many years until there's a truly comprehensive system of native lenses for those cameras... Plus those lenses cost more than their DSLR/SLR counterparts and who wants to ditch all they already have!

All this is not to suggest buying one of the Canon cameras. AFAIK, that wouldn't be good combo, even with adapters unable to share lenses with a modern Nikon system.

The point above is that I've changed my mind about adapters. They're a minor inconvenience, at worst. They can offer other useful features, in addition to adapting the lens. And, at least in Canon's case, apparently make for as good or better than ever lens functionality... AF, IS, aperture control, etc.

I was not aware of some of the Nikon Z-series camera limitations mentioned in responses above (no "screw drive" motor for AF Nikkors, struggling AF in low light).

In answer to the original question....

How about a Sony mirrorless for that second camera?

The reason I ask is because I know for certain there are adapters that allow Canon lenses to be used on Sony cameras, with full support for good performing AF as well as aperture control and, if the lens has it, image stabilization. The adapters basically allow virtually any full-frame capable Canon lens made the last 30 years to be fully usable on Sony's full frame mirrorless. I am pretty sure there are similar adapters for modern Nikkors on Sony cameras. Might be worth a look. The Canon to Sony adapters ain't cheap, so I'd assume the Nikon to Sony would also be expensive. But it may be worth it, if it allows a Sony mirrorless to share lenses with a Nikon DSLRs. An adapter also would cost a lot less than replacing or duplicating a large kit of lenses, if it were even possible to find comparable lenses in the new mount.

There's the 24MP full frame Sony A7 III. And there's the 46MP full frame A7R III (which appears to use a sensor pretty similar to the D850's). I would expect some sale price discounts on the latter, now that it's replacement A7R IV (61MP) has been announced, due to be in stores in September. Besides price reductions to clear the shelves of the older model, there also will surely be some current users upgrading to the new model, trading in their A7R III's and bolstering the supply of them on the used market.

EDIT: I found these Nikon F-mount to Sony E-mount adapters that appear to fully support all lens functions (AF, VR, aperture):

https://www.bhphotovideo.com/c/product/1386923-REG/fotodiox_nikg_snye_fusion_mrkii_nikon_fusion_sony_nex_auto.html
https://www.bhphotovideo.com/c/product/1456833-REG/viltrox_nf_e1_auto_focus_mount_adapter.html
https://www.bhphotovideo.com/c/product/1349066-REG/vello_lae_se_nfv5_nikon_f_to_sony.html

speters Loc: Grangeville/Idaho

If I were you, I would just use another 850!

russraman Loc: New York City

I have a D850 and two Nikon Df's, which I love. If I were to add (gulp) a fourth Nikon camera to my arsenal, I'd go for a crop-sensor D500 to go with my D850. The D500 is destined to become (if it hasn't already become) a legendary Nikon camera, and its relatively compact size coupled with FX lenses would be a powerful complement to the D850 for wildlife, sports and action shooting. Check out some of the YouTube reviews for the D500. A couple of informative D850 versus D500 comparative videos: https://www.youtube.com/watch?v=_17fkPddCms and https://www.youtube.com/watch?v=NJSAAMcLMZo

CO

Theoria Apophasis, the angry photographer on Youtube, thinks the D500 is going to be a legendary camera. I have two of them.