Description
This adapter plate fastens onto the bottom of a TL-120 camera and allows you to use AA batteries instead of under-powered button cell batteries.
The main body of the plate is 3D-printed plastic (PLA). Note that this material may warp when exposed to temperatures greater than 60 °C (140 °F), for example, if left in a car during the summer. I did not feel comfortable attaching my tripod directly to a plastic part which interfaces to the TL-120. To address this issue, I machined a small stainless steel insert. The plate is attached to the camera with a single 1/4″-20 screw through this metal reinforcing plate, and this plate has two holes tapped for 1/4″-20 (spaced 1″ apart) so you can still mount the camera to a tripod. Even if the 3D-printed plastic were to fail catastrophically, the camera should not fall off your tripod.
To install the plate, all you need to do is remove the existing battery holder and fasten the plate into the tripod thread on your TL-120. The positive connection is made via a brass screw which protrudes into the battery compartment. The ground connection is made through the stainless 1/4″-20 mounting screw (included). The wires are enclosed in a cavity between the camera and the plate so they cannot be snagged. Nothing is glued, and everything can be disassembled for repair or modification. A switch allows you to cut power to the camera which may be useful, for example, if you are concerned about the meter button being activated in your camera bag and draining your batteries. A “trigger guard” prevents accidental actuation of the switch. The film door and spool-retaining pins can be operated without removing the plate.
One potential source of irritation is the commercial injection molded battery holder that is fastened to the plate: it is far too tight for my taste. There is no possible way that your batteries will fall out! It is rather challenging to install the batteries and you need something to pry them out when you want to remove them. Thankfully, if you use low self-discharge batteries, I would think they would last a very long time, likely more than a year. A hinged cover hides and somewhat protects the batteries. The electronics are not weather sealed, but neither is the camera.