Herco

Hi and welcome to Fuji 😉
I'm not so sure about the D750 being outdated and so... It is still a great camera used by lots of professionals as well. To be really honest even today's best mirrorless cameras re. auto-focus like Sony's A7RIV and A9II are still not as good in AF as the best DSLRs (among which I also count the D750 and D810).
Fuji's AF has become quite good in the latest generations but there are a few caveats. First, your 16-80 lens is a recent design with fast AF performance. The 55-200 however, is a bit older and is fine at best re. AF. So, your best results will probably be with the 16-80. The f4 limitation of that lens however, will limit the low light AF performance of the X-T4 a bit.
The X-T4 offers various tweaks to adjust AF to the circumstances. This is a bit cumbersome as it is not really good in auto detecting the required setting. You will have to do that for the camera. You can designate some options to function buttons on the camera for future quick access.
Here's my recommendation:
Set the AF mode to AF-C (front of camera). In the menu 'SHOOTING' and sub-menu 'AF/MF Settings' select mode 5 in the AF-C Custom Settings. This is for erratically moving subjects. This sets the tracking sensitivity to a locked-on mode, the tracking speed to the quickest and the zone area to auto (as the dogs move back and forth). It is a good starting point for further tweaking. Once you've find the best setting you can store that under custom AF-C mode (mode 6). Then make sure that the number of focus points is set at 425 for the widest coverage of focus points unless you follow the dogs with the camera and keep them center-frame. Switch Pre-AF on. This speeds up the focusing process when you half-press the shutter release button. Unfortunately the X-T4 doesn't recognize animal eyes, so face-AF and eye-AF doesn't help here. Best to switch that off and prevent the camera from scanning for faces/eyes. I've seen the X-T3/4 recognizing faces while they were not there (in shapes of leafs and so). You may also want to test release/focus priority. With focus priority usually you have the best hit rate for in-focus shots, however, it may also result to your camera when losing track of the subject instead refocus on a different subject. I'd recommend release priority in that case. You may have more shots out-of-focus, but at least more to choose from as well.

Have Fuji forgotten the XT30? The XT3 got an update that allowed it to be used as a web cam, its just had another update to upgrade its focus performance to XT4  levels. I'm beginning to wish I'd stayed with Nikon or gone for a Sony. Having said that, Fuji's own XS-10 looks great. Why would anyone buy an XT30 now? it seems suddenly very old and unattractive.

Rico Pfirstinger wrote some books on Fuji X-cameras incl. a few pages on DR. It's in all of his X-pert Tips books. Furthermore, cambridgeincolour.com has extensive explanation pages on all sorts of photographic topics. Just search on their site for dynamic range. The key is that you cannot correct blown-out highlights but it is easy to correct deep shadows in post processing. Cameras have two ways of addressing this: either an HDR-feature or an extended DR feature. 
The extended DR-setting on the camera works for jpegs. It typically underexposes your raw file by 1 or 2 stops and than with the in-camera raw conversion to jpeg it leaves the highlights as is and amplifies only the midtones and shadows to produce a jpeg with detailed highlights (because under exposed) and nice blacks and greys (corrected in camera). Effectively its 1 extra stop of DR in practice.
The HDR feature actually creates multiple images with an exposure bracket and combines these images into one, using the highlights of the underexposed image and the shadows and midtones of the other images. HDR can also be used for raw images in post.
As for your typical situation, you only use raw-files and no jpeg I believe. Best approach IMO is to leave the DR setting to 100% and do the exposure correction in Affinity Photo. In order to do that you should set the live view function on to see the effect of the exposure on screen and switch on the histogram. Than set the exposure in such a way that the highlights (right part of the histogram) do not blow out. So stay within the border of the histogram at the right. The shadows might get blocked and the midtones way darker than you want, but that is easily corrected in post with the Shadow and Midtone sliders.
By using this method you can use the base ISO of the camera (ISO100 in case of the GFX50R) which is always preferable in landscape photography. The fact that below ISO320 the camera limits you to DR 200% is because it needs 'room' to do the corrections.  From 320 to 2 stops down is ISO80 which the camera cannot handle (ISO100 is the lowest) without trics like extended low ISO which you should only use as a last resort. 

The 27 makes sense if you want to carry the camera in a pocket of your jacket or so. The body itself is too big for any other pockets anyway. If you carry the camera on a strap or in a small bag there's little point for a pancake lens anyway (over the 23 you already have). Note that the 27 doesn't have an aperture ring. If that's important to you (as it was for me), discard that lens. Also noteworthy: there are persistent 'rumors' about a MkII version of the 27. You may want to wait for that because it could boost IQ or it will lower second hand prices for the MkI version. Personally, I prefer the 35/f2. Though its not as small as the 27, the difference is not huge and the IQ of that 35 is stellar considering the price. It also combines nicely with the 23/f2.

Rico Pfirstinger wrote some books on Fuji X-cameras incl. a few pages on DR. It's in all of his X-pert Tips books. Furthermore, cambridgeincolour.com has extensive explanation pages on all sorts of photographic topics. Just search on their site for dynamic range. The key is that you cannot correct blown-out highlights but it is easy to correct deep shadows in post processing. Cameras have two ways of addressing this: either an HDR-feature or an extended DR feature. 
The extended DR-setting on the camera works for jpegs. It typically underexposes your raw file by 1 or 2 stops and than with the in-camera raw conversion to jpeg it leaves the highlights as is and amplifies only the midtones and shadows to produce a jpeg with detailed highlights (because under exposed) and nice blacks and greys (corrected in camera). Effectively its 1 extra stop of DR in practice.
The HDR feature actually creates multiple images with an exposure bracket and combines these images into one, using the highlights of the underexposed image and the shadows and midtones of the other images. HDR can also be used for raw images in post.
As for your typical situation, you only use raw-files and no jpeg I believe. Best approach IMO is to leave the DR setting to 100% and do the exposure correction in Affinity Photo. In order to do that you should set the live view function on to see the effect of the exposure on screen and switch on the histogram. Than set the exposure in such a way that the highlights (right part of the histogram) do not blow out. So stay within the border of the histogram at the right. The shadows might get blocked and the midtones way darker than you want, but that is easily corrected in post with the Shadow and Midtone sliders.
By using this method you can use the base ISO of the camera (ISO100 in case of the GFX50R) which is always preferable in landscape photography. The fact that below ISO320 the camera limits you to DR 200% is because it needs 'room' to do the corrections.  From 320 to 2 stops down is ISO80 which the camera cannot handle (ISO100 is the lowest) without trics like extended low ISO which you should only use as a last resort. 

Though I don't use Affinity Photo and I therefore can't check it, it is most likely caused by the Dynamic Range setting. By setting DR to 400% you're essentially underexposing by 2 stops. I know that Capture One reads the RAF-file and adjusts accordingly. It's very likely that Affinity doesn't do that. Whether it's for all Fujifilm cameras or only for this one (GFX50R?), I can't tell. RAF-files from the GFX cameras are different from the X-Trans cameras. Even between the different models there are variations, hence that software specifies not the sensor type/generation but specifically the camera model. 

Hello everybody,
New Fuji owner from Michigan here. 😊
I've been a photographer since the 80s and have been shooting digital since 2003 (almost exclusively Canon.) Being someone who learned with film I've always had a pretty nice collection of vintage lenses and while they're alright on my DSLRs I've always wanted something a little better from them. I missed the look they gave me on my old film bodies. Since Covid-19 has kept me from working I felt it was a great time to explore mirrorless and other systems.
Recently I was able to buy myself an used X-E2 body in excellent condition! All my vintage lenses have been so awesome on it! Playing around with film simulations are an experience that has my feeling like a teenager when I first got into photography. The size and style of the X-E2 is practically perfect for me and since I only shoot with manual focus it's like a time machine bringing me back to the 80s and 90s when everything was new for me and I was so eager to learn. 
Of course the more I learn about my little camera the more I want another one. Someday I hope to afford an X-Pro2 or 3. I think those might be my dream camera.
I look forward to learning new things and exploring what I can do with my Fuji. I even find myself revisiting old lessons I've studied so long ago I've forgotten most of it.
 

For the X-Pro2: in the shooting setting menu, you'll find the option 'mount adapter setting' where you can define where you can define up to 6 lenses you use via an adapter. When you select the lens, the (closest possible) image frame lines will be displayed in the optical viewfinder.

Allen,
Which car is "better" ? A Porsche, a Land Cruiser or the 5 ? I mean, it is not a question of better or worse, it is a question of better for a certain purpose. The 50 f1.0 is rather extreme, in DOF, price, size, weight, speed (low light capability). For the vast majority of normal photos I would argue the f2 is just as good and also small, light, inobtrusive and great value for the price. It focuses very fast, is sharp and WR. DOF at f2 (e.g. for portraits) is shallow enough for me. Maybe you have more extreme needs than I do so you have to decide based on that. I would refuse to make a general statement as to which of the 50 f1.0 / f1.2 / f2 is "better". For me the f2 is better. Go to a shop and try them out if you can. Good luck !  Let us know how you fared.
Cheers

...and the EVF Brightness on 0 (instead of Auto). 

AFshoot.com has a silver one for the XF50/f2. It's a 'vented metal lens hood' so more similar to the metal lens hood for the XF35/f2 and the XF23/f2 rather than the original plastic one. Also it is a screw-on model with a filter thread instead of a bayonet. Nevertheless it fits well and the price is great (just EUR 11.50 or so).

Film simulations only affect the jpegs, not the raw files. However, in the data of the raw file Fuji also stores which film simulation is used (if any). SilkyPix and CaptureOne use that information to display the raw image as per the selected film simulation setting. You can easily switch that off (In C1: Base Characteristics -> Curve). When it is in 'auto' it will pick up the film simulation you've used in the camera. When you put it in 'linear response' it is the flat raw file without film simulation.

Without knowing your shooting preferences and style it's a hard question to respond to. In case you look for something longer than the 23mm (35mm FF equiv.), the 35, 50 or 56 are all great lenses. Depends on how much longer you need. The 56 has by the way the same filter thread as the 23 which can be convenient. If you really need 'long' then the 55-200  or the 50-140 are good additions that won't make your 23 redundant. The 50-140 however is well-over $1000, but you can look at used ones.
In case you want something wider, the 16 or even better the 14 or the 12mm Zeiss are great additions to your 23. Esp. the 14 pairs nicely since it has the same manual focus clutch as the 23 (in case you focus manually at all). The 16/f1.4 also has that, but might be too close in focal length to the 23.
As for zoom lenses, I guess you bought the 23 for a reason. The issue with buying a standard zoom next to it (like the 16-55 or the 18-55) is that you probably leave that on and might not use the 23 that much anymore. That is a pity since in terms of IQ it is one of Fuji's best lenses. Adding the 10-24 (which is on sale) is perhaps a better alternative as the long end (24) of that lens isn't the best part of that lens, which keeps the 23 a good extension.

The size of the photocells in the 24Mp sensor is approx. 8% larger than in the 26Mp. The gain differs about 20% so there is certainly an advantage for the 26Mp sensor. However, with higher gain there's also slightly higher noise. To correct that, the NR profile of the 26Mp is slightly different. The end result is barely visible in real live low light RAWs (in Capture One). That coincides with the Sony specs for the sensors. Both 24Mp and 26Mp sensor are from Sony and the 26Mp in Fuji is the same sensor as the 61Mp in the A7RIV and in the GFX100. Only cut to a different size.

There's a lot of misconception re. the sensor generations Fuji uses. In essence there's no visible image quality difference between the 24Mp X-TransIII/Processor and the 26Mp X-TransIV/Processor. The 2Mp are negligible. There's virtually no visible difference in low-light performance as well. The BSI (back-side illuminated) technology of the 26Mp sensor has a theoretical advantage here because the metal wiring layer is not on top of the photocells, but beneath them. However, the photocells of the 24Mp are larger and therefor the yield of the 26Mp BSI-sensor is lower than the 24Mp FSI sensor (front-side illuminated). That glitches out almost all advantages here.
What does make a difference is the number of AF pixels on the 26Mp sensor (much higher) and the shorter circuits due to the BSI technology of the 26Mp sensor. That allows for greater throughput capacity and quicker AF. Top that with a more powerful processor in the 26Mp camera's and you have snappier AF and higher video bit rates (up to 400 Mbps).
The main differences between the x-pro2 (I'm a long-time owner) and the x-pro3 (tried it extensively) are the LCD screen and the viewfinder. The hidden LCD screen could be very beneficial to a street shooter (from the hip). However, imo it sucks to have to open it for menu access and menu access through the EVF is cumbersome when you wear glasses (and have thumbprints all over them). I prefer a screen like the X100V were the user has options to choose how to use it and which is nicely integrated in the body. The sub monitor is imo a useless gadget as there's not backlighting button like on the X-H1/GFX50S. 
The viewfinder for me is the real dealbreaker on the X-Pro3. Though it is larger and brighter, in OVF mode (which is why I bought the X-Pro) there's only one magnification left (x0.50) rather than the 2 magnification levels of the X-Pro2. That renders the X-Pro3 in OVF mode useless for lenses shorter than 23mm and longer than 35mm. I can't use my 16/18mm and my beloved 50mm anymore on the X-Pro3 in OVF unless I settle with a very tiny frame or frame lines outside my OVF. For now I'm sticking to the X-Pro2.

The only way -to my knowledge- to prevent the camera to go to My Menu every time you enter the menu button, is to leave the My Menu completely empty. The purpose of My Menu is to have quick access to the most used menu items, hence it always starts there. Should  you decide not to use the My Menu, you can always add 4 most used feature to the Q-menu and activate them with the Q-button and the touch interface of that menu.
From what you describe the 18-55 can do a couple of things in the background. When PRE-AF is ON, the camera will always focus. It could be that it still does when in replay mode (I haven't checked it as I don't have that lens). Another (more likely) noise could be that of the OIS. On the 18-55 there's a switch for that. Try it in OFF mode and see whether the noise persists.
The focus peaking for manual focus indeed needs an upgrade. I also have experience with an A7RIV and an SL2 and they have better focus peaking esp. during magnification. Esp. the A7RIV with the Loxia lenses works brilliant. The issue with Fuji is that indeed when magnifying the peaking gives a very flickery image. So either quiet it down of switch FP off when magnification is activated. Another issue is that for some Fuji cameras (e.g. my beloved X-Pro2) the focus peaking color yellow is not available for some inexplicable reason. Yellow is for most shooting situations the most visible color (at least in my experience).
Another issue is that for many menu settings there's no help function or explanation in the menu. After many years of Fuji I know most settings by heart, but it took me a while. It would be easy to have a line of text explaining the menu setting at hand. Most other cameras have such a feature. Fuji only does this for certain settings like film simulations, but consistent use would improve the usability.
Finally, some menu options are named differently on the various Fuji cameras. On the X-Pro2 there's the option "preview pic. effect" which is called "natural live view" on the X-H1. Those things can be easily aligned, even though there could be a small tech. difference between the two options. Other than that I think the Fuji menus are quite good and at least a lot clearer than the older Sony menus (not the A7SIII) but not as good as the Leica and Canon menus. It sits nicely in between 😉

You should try and assign other features to the front dial command and see if it acts similarly. I've had this issue with an X-Pro2 (though with the back command dial) and it turned out to be a moist-issue. It started after a walk in some mild rain on Iceland and only after the camera was serviced it disappeared... Could it be the same issue for you?

The 'Fuji-colors' are mostly a product of the JPEG-engine in the cameras. While there is a slight difference between the 16MP and the 24MP, most differences are due to the JPEG engine and between lenses. Some of the older lenses (the fast 23, 35 and 56) have a 'special' film-like quality. It has mostly to do with how they render color and contrast. Using these lenses on the newer cameras, results in the same effect. Fuji-purists sometimes praise the older 16MP sensor for its character, but to my eye the 24MP sensor is just as good and has the resolution to do additional cropping. I've owned 6 Fuji cameras over the past 9 years (and still own 2) and the newer cams are just as good as the older ones (if not better).
I've had the XP1 but upgrading to the XP2 didn't affect the colors in RAW. In fact, the JPEG-engine in the newer cams (like the XP2 and the XE3) can also control the film grain and has a few more film simulations that can be an advantage. Esp. Classic Chrome can be made to look similar to the 'Leica-look' (I've used a/o the M8 and the M262).
To learn more check out fujiweekly.com and the film recipes outlined there. Also check-out the RAW and JPEG manuals of Thomas Fitzgerald. He gives very good advise on how to set sharpening and noise reduction. Fuji's JPEG engines are too aggressive to my liking, so I dial down NR to -2 or -3 on the 24MP-cameras and Sharpening to -1 or -2. I use Capture One as imo it works way better with RAF-files than LR.
PS. with the new XP3 out, second-hand prices for the XP2 dropped. While not as low-priced as a used XE3, an XP2 is now great value-for-money. 

For some reason Fuji cameras are quite susceptible to read/write errors on SD cards. I've had multiple issues (incl. lost images) with several different Fuji cameras, so I use the following 'workflow' to reduce the chance of error:
always use Fuji recommended SD cards use two exact same cards if the camera has two slots insert them gently straight in and out format both cards in the camera before a shoot regularly copy (not move!) all images on the card to your computer then (re)format both cards in your camera (never on your computer) do not take out one card to view images on a computer/tablet and then put it back in the camera for further shooting (I share the images via my phone to a Dropbox to view them on bigger screens. Or in the studio I work tethered.) That way you don't have to select and delete images one by one or by group in your camera, which is a tedious process.
In general: SD cards are not meant for long-term storage of images. Just for shooting and transport to your safe storage on a computer and back-up drives.

Without knowing your type of photography, I would guess that the 18-135 will in practice replace your 16-50 (unless you need its compactness). The 55-200 is much more an extension of what you already have. Both are fine lenses, but designed for different purposes.
The 18-135 is Fuji's version of a 'super zoom' lens: a lens with a zoom factor of at least 7x to 10x zoom. Usually these super zoom lenses suffer from a lot of compromises, but this is actually quite a good one with good 'sharpness' and contrast except perhaps for the far corners and edges. It's a true 'travel lens' that for many people is almost 'glued' to their camera. Together with the 10-24 you'd have a very universal combo. However, don't expect it to have 'exquisite bokeh' and shallow depth-of-field for portraits. Around 50mm the max. aperture is f5, so the DoF can't be really shallow. The OIS is very good so the smaller apertures can be compensated with longer shutter speeds without blurred images due to camera shake.
The 55-200 is a true tele zoom lens. Not a lot of people need the longer focal lengths (beyond 200mm in full frame equivalent terms or 135mm in Fuji's APS-C format), but if you do -like for sports, wildlife or landscape details- it's a very good lens. In pure sharpness it even 'beats' Fuji's professional 40-150 tele zoom, but that one has a bit better contrast and a constant f2.8 aperture. I would not worry too much about the Weather Resistance (WR) thing. First, your camera isn't WR, so that is the limiting factor. Secondly, if you take a few precautions, also non-WR lenses can be used in a light drizzle or rain without you worrying about it. My guess is that you're not the photo reporter waiting in the downpour for that perfect shot in a football match. The OIS in the 55-200 however, is very useful when you start zooming in. At 200mm (300 in full-frame) it becomes hard to carefully focus and keep a steady shot. 

There’s another reason not to depend on Fuji’s X Raw Studio. It only allows you to process raw files captured by the exact same type of camera with which the shot was made. When you upgrade your Fuji camera to a newer model you can’t process the raw files made with the older camera anymore. So moving up from an X-Pro2 to an X-Pro3 and your older files can’t be processed in XRaw Studio... 

The main benefit of the 24Mp sensor in the X-E3 vs. the 16Mp sensor in the X-E2s is that the 24Mp gives you more room for cropping your image. The visible difference in (un-cropped) image quality you'll only start to notice in larger prints (larger than about 30x45cm). A main advantage of the X-E3 over the X-E2s is the much faster and decisive AF, although that also depends on the lenses you use. For me the joystick is a real benefit. The cleaner back without the D-Pad gives me a natural resting place for my thumb without the risk of unintentional operating D-Pad buttons. You have to take into account that you have a few less buttons to configure freely though...

I guess your goal is to have the face stand out and the background 'disappear' in the shadows. Spot metering can be tricky since it very much depends on where you aim. There are great differences in luminosity in the face. If you need perfect exposure there are two options:  (1) meter on a grey card near the face and fix that reading in manual mode or (2) use a separate light meter for ambient light reading near the face. Both options are a bit cumbersome though. The multi-metering mode of Fuji is quite good and will take the focus point into account. So when you focus on the face and expose, it will know that is the main subject. However, to get the darker shadows, you may want to correct 2/3rds or 1 stop with the exposure compensation. In general make sure you don't overexpose on the left side of the face or on the shoulder, since in post processing it's easier to correct a slightly darker image than an overexposed one.

Third party options of adapter ring that screw onto the lens combined with a good UV- or protection filter work just as good. I believe JJC has a good one. Make sure the optional lens hood works with a bayonet. That's easier than a filter thread screw-in one.

I’m not sure that the new lens has less resolution. The ‘old lens’ was designed for a 12/16Mp sensor. I’ve once read that Fuji designs the current XF lenses for approx. 32Mp max.
Nevertheless I can tell you the new lens is a clear step up. The ‘close focus haze’ is gone and that alone was for me a big improvement compaed to the The typical corner softness is mostly gone and visually I’d say that the V is now at least as good as the XF23/f2 (if not better). Having said that, the XF23/f1.4 still ‘beats’ the two f2’s. In contrast, micro contrast, color rendering and overall sharpness.
The question is where do you use it for? Typical street and reporting photography often doesn’t need razor sharp corners. Portability and inconspicuous format are more important. The Summicrons and the Voigtlanders aren’t perfect either, but they have a kind of ‘magic’ that the X100-series has too. I think you can call that ‘sprezzatura’ (the imperfection that makes perfect). For pixel peepers and e.g. critical landscape and archtecture work I’d recommend the 1.4.
However, dpreview.com has X100V sample RAF-files you can download and peep for yourself. They also did a good comparison of IQ between the V and the F.