I dabble with Bryce from time to time and I'm getting back into it at the moment.  I've got a really nice scene with some great buildings and towers but every time I go to render it the perspective bends all the towers in at the top.

I've tried to search the net for answers but I've drawn a blank.  What I want to do is to render the image but leave straight things like really narrow towers looking straight.  I've attached a quick render to show you what I mean.

Help.