Introduction: Modify Tamron 70-300mm Macro Lens to Switch on Macro Mode at 70mm
My first instructables submission :) In 2008 I discovered that the Sigma/Tamron 70-300mm lens contains a trick where you can extend the capability of the focusing distance. The older video I made in 2010 can be found here: http://youtu.be/byEkToJ0yTU
Basically, the lens has a 'macro mode' button. The button can only be use when the zoom is between 200~300mm (Sigma) or 180~300mm (Tamron). I discovered that the button is just a stopper, the focusing mechanism is capabible of zooming at 0.95m anytime if you remove the stopper. Even though one should modify their lens at their own risks, I am sorry that some feedback shows they messed up their lenses.
Therefore, here's the more detail step-by-step video.