Focus Puller for Sony HDR-CX900

thingiverse

I was searching for a low-cost method of adjusting pre-set focus depths on my Sony CX900 and came up with a solution. This involves three components - a 'reference' piece which is positioned in front of the focus ring, without obstructing it, and two 'slider' pieces which are attached to the focus ring. By aligning your desired focal points while holding the focus ring steady and moving one slider to the corresponding position, you can set up multiple depth positions. Once established, you can effortlessly switch between initial, secondary, and tertiary focus points (with two sliders), and even make rapid focus adjustments between them, should that be required in a scene, like during a conversation between characters at different depths of field. You can view a concise video demonstration here: http://youtu.be/OLc7UguKMm4. Please note that when adjusting the positions of your slider pieces, do so with the same speed you intend to use for filming. If not, the camera may not capture the full focus shift distance due to motor limitations, causing the lens to lag behind the focal position. To work around this issue, consider using a steady and consistent pull speed that mirrors the one used during recording. Should anyone have suggestions on mitigating this challenge with my specific camera setup, I would appreciate their input!