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Tolerances don't lie...and stories of the Grand Canyon!

There has been much written over the years about the generation of optical system fabrication, assembly, and alignment tolerances leading to a performance error budget and predicted system performance. Over my 40 years of optical design experience I have become increasingly more cautious (and concerned) about how accurately we, the optics community, are tolerancing our systems and predicting their manufactured performance. In this paper I will share with you some of these concerns along with recommended ways of avoiding the many "speed bumps," "pot holes," and other common issues encountered when tolerancing. And of course I will reveal why "tolerances don't lie" and how this relates to the Grand Canyon.