Pixco Adjustable Aperture Speed Booster Full Manual Operation Focal Reducer Durable Mental Lens Adapter For Turbo Nikon G Mount Lens to Micro 4/3 Camera It converts fullframe lenses into APS-C lenses. The advantage is to get the fullfame field of view onto the APS-C sensor. Feature:Increase exposure to 1 stop, and you can use faster shutter speed to shoot an image. Works fine, closely combined with the bayonet smooth, like the original lens. Full manual operation, manual focus, manual iris adjustment can be achieved with body manual exposure, aperture priority exposure, combined infinite focus. Note: You must set the camera to "Shooting without lens" mode to ON before use.Avoid direct shooting to light sources, or otherwise blue spot occurs.