I am going to visit my son in San Antonio Texas. Can someone please advise me what focal length lens for a 35mm camera will be required to photograph the exterior front of the Alamo mission. Not knowing the stand-off distance of the site or the scale, I have no idea how wide of an angle lens to bring on the trip. If you have only shot the mission on medium format, this is ok as I can convert MF coverage to 35mm coverage easily. With thanks, Sam H.