Besides the increasing use of adaptive optics (AO) on modern telescopes, active optics (aO) are still of high importance to optimize Image Quality (IQ) for non-AO instruments and decrease the dynamic range needed for AO corrections. We will describe the design and operation of an optical alignment bench used to calibrate the aO models of the peripheral wavefront sensors. This setup is used to determine optical models in stable conditions in the laboratory and thus optimize wavefront correction on the sky. We will show results of this technique applied to our 2x2 Shack-Hartmann wavefront sensor used for tip-tilt-focus-astigmatism correction of all our non-AO instruments. We will also review some sub-systems performance monitoring tools and finally gauge the performance of active optics on the Gemini telescopes by analyzing the delivered image quality for various instruments.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.