I needed a solution that allowed me to optimize the back focus of my scope by providing a level of adjustment for fine tuning. The Baader Varilock is a single tool that allowed me to do this without having to purchase and install multiple different tubes. For me, it provides greater flexibility and ease of use that will pay for itself over time.
However, figuring out how to adjust the level of extension was made difficult by the lack of instructions and misleading symbols stamped on the device. Because of the way my brain works, I wasted time trying to figure out the symbols rather than understanding the design of the device. If your brain works like mine, read on to save some time.
The Varilock is composed of 3 rings. The first ring has markings on it that indicate the amount of extension. You identify this ring by it's small white lines. You may have to twist the ring out a bit before you see the white lines. The middle ring is smooth and has symbols with arrows. One arrow to "Release" and an arrow pointing in the other direction to "Lock". Forget them, just use the middle ring to hold the device while you turn the other two rings in and out of the middle ring. The third ring is bare with no markings.
(1) Holding the middle ring, twist the ring out that sets the amount of extension and set it to the desired amount. I believe each white line indicates 1 mm of extension.
(2) Hold the middle ring and with the other hand, twist the other ring inward until it hits the ring with the white lines. Tighten and voila your extension size is locked.
