Gerd Ludwig on His “Invisible Flash” Technique | PDNPulse Photographer Gerd Ludwig, a master of TTL strobe lighting, discusses his technique for invisibly blending hand-held flash with available light. via PDNPulse: http://pdnpulse.pdnonline.com/2016/09/gerd-ludwig-invisible-flash-technique.html Ludwig explains the basics of his technique. He shows how he has applied it to images from his various assignments for National Geographic … Continue reading Gerd Ludwig on His “Invisible Flash” Technique | PDNPulse