HS50EXR the XS-1 replacement?

Yes and no, total light makes a lot of difference, and the Fuji's 1/2" sensor is slightly larger than the Panny's 1/2.3" sensor.

Pixel density makes a difference when we compare the way JPEG engines treat the RAW output. Noise reduction is often heavy handed at high densities. So the Fuji's 16mp is an issue when shot at full resolution. But the Fuji EXR sensor can be shot in a blending mode, where adjacent pixels of like color are "binned", or more accurately "blended" on a curve with half the pixels underexposed to protect highlights. DR400 gives an extra 2 stops of highlight protection and this makes an enormous difference in image quality in places where there might be dappled sunlight (like everywhere :-)) ...

But ... the Panny has one real advantage ... it has the 2.8 constant lens. This means that it has a 2 stop ISO advantage at full zoom ... and that might be enough to make the difference. I have seen no tests that illuminate this difference however ... the HS series is just not popular enough with reviewers. Even DPReview are ignoring it completely. And even those few who look at these cameras do not shoot them properly, in blended mode DR400.

One day perhaps someone who has both will see if the HS series can be processed to match ... but we can assume that in deep woods you would shoot the Panny at 400 iso while you would shoot the HS at 1600 ... and that is likely to be too much to overcome.

One more thing ... the HS50 will have 1000mm ... it is unlikely that Panny can ever match that at 2.8 constant ... so if you are in really bright light a lot, and if you shoot tiny birds, and if the HS50 EVF can actually handle that magnification (i.e. is fast enough and clear enough) then the HS50 might have an unbeatable advantage.

Until we see a sample or a preview, who knows ...

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http://kimletkeman.blogspot.com