The designers of the Dynax autofocus cameras believed that releasing the shutter without a lens attached was not desirable and therefore created a safety feature to prevent it. You can use your Dynax with a telescope, microscope, or lens without electronic connection by pressing a combination of camera controls while switching the Camera ON. Consult the table below for the proper sequence for your camera. 5000, 7000 9000, 3000i, 5000i, 7000i, 8000i No preparation needed to use 2xi, 3xi SPxi Use of T-mount lenses, microscopes, and telescopes is not possible. 5xi Press and hold SPOT and FUNC. buttons and switch from LOCK to ON. 7xi/9xi Press and hold AEL and FUNC. buttons and move power switch from LOCK to ON. 300si Press and hold FLASH and DRIVE/SELFTIMER buttons and move power switch for LOCK to ON. (Off appears in LCD panel) 400si Press and hold Drive Mode and AV buttons and move power switch from LOCK to ON. 500si Press and hold Drive Mode and SPOT buttons and move power switch from LOCK to ON. 600si Press and hold the LENS RELEASE button and FILM SPEED button and move the power switch from LOCK to ON. (OFF appears in LCD panel) 700si Press and hold SPOT and CARD buttons and move power switch from LOCK to ON. 800si Press and hold SUBJECT PROGRAM and AEL buttons and move power switch from LOCK to ON.(OFF appears in LCD panel) 505si/505si super Press and hold the Selftimer-Drive Mode button and Spot/AE button while sliding the Main Switch to "ON." (OFF appears in LCD panel) 404si Move the function Dial to Multiple Exposure. Press and hold the Program Reset and Selftimer-Drive Mode button while sliding the Main Switch to "ON." (OFF appears in LCD panel) 303si Press and hold the Selftimer-Drive Mode button and Subject Program button while sliding the Main Switch to "ON." (“OF” appears in LCD panel) Dynax 4, 5, 7, 9, 5D, 7D Custom Function. See camera’s instruction manual Dynax 3 Press and hold SUBJECT PROGRAM and Drive Mode buttons and move power switch to ON (OF appears in LCD panel) Vectis S-1 Press ON/OFF to turn camera ON. Open door that covers hidden buttons. Press the Drive Mode button (fathest on the left) and the MODE button together. "ON" will appear in the LCD panel. Press the "SEL" button (second from right in hidden buttons). "OFF" Will appear in the LCD panel. RD-175 Press and hold SELFTIMER and AV buttons and move power switch from LOCK to ON. (ON" appears in LCD pane) Konica Minolta does not offer an accessory for using Dynax cameras with other optical devices. Damage from use of an adapter will void the warranty.