I checked out the Nikon version of this adapter. Amazon reviews are mixed. Does this device have optics in it? Reviewers said it doesn’t have a way to keep the camera from rotating when in use. Some say they had to rig spacers to keep the adapter from going too far in the microscope tube so they could focus. Some said the final photo image was not as sharp as what they saw through the microscope. Can you comment on any of this?