There is nothing wrong with that. That actually goes with what I saying about being able to take in the whole image. As a poster, it is going on a wall where you can see the full image in it's entirety, all at once. The average "Wall" for a monitor viewing the internet would be a little less than %50 of what you have as the image size.
I agree with Star. I would say to get a better over all concept of this, maybe shrink the image so more of it can be viewed on the screen. This particular image loses something when you have to scroll to see it all.