Hi there, I had posted my modification some time ago, just made a better tutorial:
http://witonosfreestyle.wordpress.c...ens-to-focus-at-0-95m-tamronsigma-compatible/
"I discovered this modification by accident in 2008 when I want to clean my Sigma 70-300mm II. I discovered that the lens is capable of using macro mode at all focal range, and the manufacture hide this feature by adding a limiter button. Later on I discovered Tamron 70-300mm, Sigma 70-300mm I as well as a Nikon mount all use the same mechanism."
If you know of any other unmentioned model, such as the Sigma gold-ring, Quantaray, and if you don't mind lending me to play some DIY as well as posting on the modifcation, please let me know!
