Ray, you keep praising of the Sony's IQ, I've never owned or used a RX1, is the IQ of the Sony significantly superior to the Fuji? (Not the DOF, the resolution, sharpness, DR, noise, et cetera.) To me significance is ISO 3200 minus and less than 100% crop.
G
Gary, at ISO 3200 and below there's not a lot of difference (although for the really serious low ISO shooters who want absolutely ZERO noise, maybe the sub-200 ISO's matter some - not me though). There probably is some pixel peepable difference, but nothing I'd ever base a decision on. At 100%, the Fuji can actually look a little better at some ISOs, because the RX1 has half again as many pixels, so until you downsample to a similar display size, it can be deceiving. I tend to use my 27" Mac screen as a default for comparison because filling that up is well less than 100% but enough to show the same kind of issues that might turn up on really large prints or otherwise large displays. I tend to look at a lot of images at full size on this screen so it also has the advantage of being a real life viewing size for me.
At that size, I can see a real difference at 6400, but its not huge. And then the really cool thing is that the RX1 is still quite good (by my street diluted standards) at 12,800 and pretty usable for B&W at 25,600, which are native ISOs on the Sony. On the X100s, 6400 is the highest native ISO and anything higher requires push/pull exposure and processing and it really falls apart very quickly at those ISOs where the RX1 holds up quite well. If you never find yourself using those ISOs, it shouldn't be an issue. I may conclude at some point that I don't really use them enough to matter, but knowing I CAN is intoxicating for now. And, for now, I'm finding reasons to use them...
The other thing, though, which I guess speaks to dynamic range, is the ability to pull detail of apparently blown highlights and buried shadows in post processing. The Fuji is really good here (although I tend to shoot Fujis in jpeg, which limits the processing latitude, although not by as much as you'd think), as is the OMD. And the RX1 is a good deal better than either. Sometimes I'l pull up shadows just for entertainment just to see how much it'll take and it'll take a lot.
In terms of resolution, I don't know. I guess there's a difference and I have noticed that the RX1 images are remarkably crop-able, on the rare occasion I've needed to. But for the most part, I'm not all that much of a high-resolution junkie - I think those are the same people who get bothered with anything above negative levels of noise at base ISO, and I'm just not that guy.
Do any of the advantages matter? Almost never. As you said, the X100s is good enough and in today's world, that's not faint praise - that's real real good. Clearly the sane thing to do would have been to get the X100s. But I just wanted to spend some time with one absolutely no-compromise, no excuses camera in my bag. You've been there - this is my first visit to that full frame neighborhood. And I like to really push the low light possibilities at this point. After I've had it for a while (and THIS camera I should have for a few years), I may conclude that it was silly and I'd have done just as well with the X100s, but its something I had to try.My one month trial run with it just sold me on it more and more, rather than making me question it, and that was a real surprise. And also, believe it or not, I really like the Sony interface more than the Fuji. Which was a bit shocking because I find the Fuji really nice in this regard. But the Sony has five fully programmable buttons that are always easily accessible, compared to the Fuji's one such button (the X100 has two with the latest firmware). And with the Sony programmed the way I like it, its as seamless an interface as any of the Ricoh's I've ever used. Which is really damn nice.
-Ray