Science for the Curious Photographer, 2nd Edition

CHAPTER 9 Coming to Terms with Real Camera Lenses

Any sufficiently advanced technology is indistinguishable from magic.

—ARTHUR C. CLARKE

 

 

 

9.1 Introduction

We have seen why compound, multi-coated photographic lenses are needed to produce aberration free images with high contrast, but we have not considered how to deal with camera lenses that often look like pipes with glass at each end. The overall length of camera lenses is often greater than their effective focal length, and it is not obvious which parameters are significant. Indeed, some extreme telephoto lenses are truly “monster lenses.” For example, the Canon 400mm, f/2.8L IS II lens is 13.5 in. long and weighs 8.49 lb; and it is not even the heaviest lens available for a 35 ...