I decided to send up a test balloon using my SMC Pentax-M Macro 1:4 Lens with Pentax k-50. Please feel free to offer up any helpful hints/suggestions. Thanks very much. TT Lens: Pentax-M 100mm 1:4 Macro Lens Camera: Pentax k-50 Photo Location: Sherwood Forest. ISO: 200 Shutter Speed: 1/125s Aperture:F8 Focal Length 100mm, Manual Exposure Mode, Used External Flash with CWA Metering. Thanks for viewing my test balloon. TT