In the heart of Wiltshire stands Lacock Abbey, home to what might be the most important window ever photographed in human history. During my summer visit to this medieval abbey-turned-Tudor mansion, I stood before the unassuming latticed window where, in 1835, William Henry Fox Talbot created the world's oldest surviving photographic negative. This revolutionary moment—born from Talbot's frustration with his own poor drawing skills—established the negative-positive process that would become the foundation…