Most commercial lens assemblies such as lenses for cameras and microscope objectives are reasonably priced (on the order of several hundred dollars) and are available immediately. A custom-designed lens assembly looks the same externally, but its cost is often more than an order of magnitude higher than the off-the-shelf assembly. Why such a discrepancy? Just what is it that makes custom optics expensive, and is it worth it? Most people who work peripherally with lenses and optics will judge the cost of a lens assembly based on what they find in the catalogs. This will often equate to the range between $200 and $1000. It is clear why the reaction to a $15,000 to $50,000 price range for an apparently similar custom-designed lens can be shocking. However, the custom lens is quite a different animal from the one in the catalog…