If it is a cabin that is on the "stern" of the ship and is looking off the back, you have an excellent location for viewing. Stern cabins are my favorite and I book them whenever I can. The view is more panoramic and you can see both sides of the ship with no worry of port or starboard.
The only negative is that no matter what location you choose the whale will always be on the opposite side.. <VBG>
Have a wonderful cruise and enjoy the cabin.