Attached Link: iPhotoForum.com

everyone seems to have covered this pretty well... although i wouldnt shoot at f/16, u risk not focusing on the all of the window and depending on how far away you are, some of it may not be in focus, i would shoot f/16 or even f/22... if your shooting film, get 100iso film, slide is even better if u can, id pick up a roll of kodak e-100vs for this. tripod is a must, if u dont have a shutter release cable, set your camera up then set the timer, that way u wont risk bumping the camera at all during the exposure bracket shoot it.. set it to f/16, meter to the right shutter speed, then underexpose by 1 stop and over expose by stop