I need accurate roof measurements but I'm really looking for accurate equipment on the roof. Good point on the roof height. The mission could start on the roof and use aero points to improve accuracy. I may need to experiment with the two cameras. How much of an issue have you experienced with the rolling shutter images. I read an article using the E90 were he used a 70 or 75 degree angle and the accuracy was much better. Would like to know if anyone else tried this. Thanks for the response