REPAIR & TROUBLESHOOTING - How To Test Lenses

This practical guide presents a straightforward and flexible methodology for testing camera lenses, developed by technical consultant Bennett Sherman. Moving beyond cumbersome approaches using complicated and imprecise test charts, this method applies proven optical principles to deliver critical and objective lens evaluations comparable to those performed by Modern Photography's technical staff and editors. The guide addresses several key areas: interpreting resolving power test charts using the USAF 1951 target, properly positioning test targets according to your camera format (35mm, medium format, or large format), and organizing test materials efficiently. Detailed diagrams (A, B, C, and D) specify the required distances and arrangements for testing lenses ranging from 50mm to over 400mm focal lengths. The kit includes a glass master target manufactured by W. & L.E. Gurley Engineering and Scientific Corp., specifically designed for these resolution-testing evaluations. Recommended magnification levels (20X to 30X) are provided for reading results accurately. This comprehensive guide serves as an essential resource for photographers seeking objective verification of lens optical performance without requiring expensive or complicated laboratory equipment.