Advice on camera upgrade from Sony S95 to a DSLR interchangeable lens camera

For landscape photography, your 3x zoom should be plenty. Most landscape photos demand wide angles. Using a long lens results in a flat image where the perspective has been destroyed, and atmospheric haze usually makes the image fuzzy and lacking in contrast and color. The context usually ends up getting destroyed, too.

A camera isn't going to give you "impressive landscapes." Impressive landscapes are /extremely/ hard to come by, and only a handful of photographers manage to produce them on a regular basis. Petteri Sulonen discusses this in his article, "Why most landscapes suck":

"Grand landscapes evoke awe, and awe is a very difficult emotion to convey. ... Almost invariably, the awe-inspiring view turns into a cutesy little postcard. Capture or display format doesn't really help -- using a view camera and making huge prints or projecting huge slides simply yields huge cutesy little postcards."

You should be able to produce good portraits with a 3x zoom, also. Presuming that your S95 has the same lens as the S90, it gives 117 mm-eq at the long end. The typical recommendations for portrait photography are on the order of 85-105 mm-eq. That's within the range of your current lens.

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