Advise on long-distance photography

I want to take pictures of ships in Puget Sound using a tripod and relatively easy to use and modestly inexpensive camera. The ships are often 3-4 miles distant and obviously the weather anywhere from bright sun to foggy. I am not knowledgeable about cameras and I don't particularly want to be at this point. That means I might fiddle a bit with settings, but mostly I want to let the camera do the majority of the work.

So far, it looks like the Canon 50SX HS is the camera I think fits the bill best. It has a 50X zoom, 12 megapixels and can be used as a point and shoot as well as allow some manual adjustments. Plus it is available for under $400.

I am not willing to spend more than $800 and I feel more comfortable with much less. This would pretty much be a dedicated camera for this function so I just want to get clear, sharp pictures of ships several miles away with a good zoom. They typically are not moving more than 15-20 knots per hour, so leisurely.

Any suggestions on a camera I am overlooking that might suit my needs better than the SX50? Or have I chosen a good one for my needs?