A neutral particle beam processing apparatus comprises a process gas inlet port for introducing a process gas into a vacuum chamber, a plasma generating chamber for generating positive ions and electrons from the introduced process gas, and a negative ion generating chamber for attaching electrons generated in the plasma generating chamber to the residual gas to generate negative ions. More specifically, the present invention is directed toward an attachment for retaining one or more lenses in position for use with light fixtures that have a housing in which the light source is recessed. The optical conditions are input to a test system which, by objective analysis, reveals a condition of the optics and an indication of the need for corrective action. A method of preparing supported catalyst materials includes contacting the sols with support materials.