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5) Edges of the OptoSplit aperture are out of focus
Observations & likely cause
• Aperture edges out of focus in both images
• Magnification and distortion to one of the split images
• A fine focus adjustment is available on the OptoSplit output port closest to the camera (see
‘Focussing the Camera on the Aperture’ instructions below). This adjustment is required if,
when initially installed, the aperture blades are slightly out of focus due to the individual
position of the camera sensor. However, this adjustment is minimal and if over-adjusted,
causes significant image distortion, magnification of one image and blurring of the aperture
occurs.
• Often, the fine focus adjustment is incorrectly used to focus the sample image, or to focus the
camera image with the image observed via the eye-pieces (bifocality). Please only adjust the
fine focus if the aperture blades are out of focus and note any adjustment should be minimal.