Sorry to be a little bit more precise here: you want the exposure to be some way depending on desired DoF and motion blur, and then you want the image brightness to come out the way you imagine it should. I am making that explicit distinction, because it may be at the heart of your issues.
If you set your camera to DR200, you will never ever be able to shoot at base ISO. DR200 requires at least ISO400. Although DR200 has a purpose, keeping the camera there at all times is, um, suboptimal. besides, when you shoot raw, you have full control over processing, so you could simply ignore the DR expansion functions, but they can come unhandy occasionally, even for raw shooters.
So, with ISO400, say, compared to ISO200, the camera will meter to give an exposure (combination of aperture and shutter speed) that will be 1EV lower. At the same time, the camera sets an EXIF flag instructing a raw converter to digitally brighten the image by 1EV to maintain the same total amount of amplification that one would get if one had set the camera to ISO200. In other words, a shot taken with the some exposure settings and at ISO200/DR100 and another one taken with the same exposure settings but at ISO400/DR200 will roughly have the same overall average brightness. Unless you are using a raw converter that doesn't recognize the DR200 flag in which case the image will come out 1EV less bright. That has happened in the past, but should nowadays no longer be a problem with decent raw converters (which one are you using, btw?).
Coming back to "within .3 - .6 of a stop": image brightness is a tricky thing. Unless you have a fully and correctly calibrated setup, consisting of a reference color/gray chart, calibrated lighting, perfect white balance, proper raw conversion, and calibrated monitor or printer, it is difficult to know whether the camera gets it right. I assume you don't have such a setup. Perhaps your way of working with your Nikon files has given you the desired results and now you find that it doesn't work so well anymore with your Fuji files. It could be a simple as increasing the brightness on your monitor. If you had had the Fuji first and worked out how it got you the desired brightness, then got the Nikon, you may have well started a thread in the Nikon forum saying "Hey, my Nikon images are coming out too bright. What's going on here?".
Point is, you probably don't not know which camera is "correct".
So, to get to the bottom of all this, I would suggest you compare exposures between your cameras. Take lenses that give you the same field of view, choose some exposure time for both cameras, set the aperture to equivalent values. That'll give you them same exposure while maintaining the same image. Then process the images however you do and compare the resulting image brightnesses. Then you will know how the two systems compare in your hands. It is common to find differences between systems, so just accept that and learn how to compensate when switching from one to the other.
Hey, thanks for the in-depth response.
A Little background on me. I have been shooting Dslr's for 10 years, got a stable of glass and always get to know my camera and lens capabilities inside and out. I have been intrinsically studying and practicing photography all these years.
I have a fully calibrated set up Eizo monitor and even the room i edit in is colour calibrated with white walls, black curtains to stop colour cast from the sun shining through them and they are always closed when editing. I have a 6500 Kelvin light bulb with a blue material swatch added to add a little more blue. Blue that my Ambient colour spectrometer told me was missing from the environment.
I have shot Nikon all these years, always had them set to Matrix metering with -.3 exp compensation and being aware of the camera's dynamic range limitations so using working around's or not even bothering to take the shot for knowing it to be too great of a task for the camera, I have had 99.9% of images correctly exposed.
Here I am with the X-T1 using the same techniques as always and Im getting exposure fluctuations. ..Oh BTW, I am shooting DR100, sorry, my mistake. I just went and checked.
I use SilkyPix for converting .RAF's, Lightroom for .NEF's and any extra work that needs doing I import the TIFF's into Photoshop.
For this occasion/Issue. I shot an image with the camera set to Raw+jpeg. The image was purposely taken with dark shadows and bright point source lights in the shot. A scenario that would make even the best of cameras struggle. In among the items in the test shot I put a piece of white paper. This white paper was the control. If the camera nailed it, I would expect the paper to be a 250 'ish white it wasn't. I had to add exactly +1.0 exposure compensation to both the jpeg and the raw file.
How does that DR setting work? I know it increases the dynamic range of the camera, but at what expense?
