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Introduction

Introduction By Andy Westlake

Our lens test data is presented through our unique interactive 'widget', which is designed to allow you to explore the optical characteristics of a lens and freely compare it to any other. Three display modes are available showing Sharpness and Chromatic Aberration, Distortion, and Vignetting; test data is presented for all marked focal lengths on the lens. Unlike some other sites, we don't concentrate purely on sharpness and present other lens qualities almost as an afterthought; we consider chromatic aberration, distortion and vignetting at an equal level. The reason for this is simple, as these other attributes will often have a more destructive effect on perceived image quality than any softness of the lens. Indeed sharpness may be considered the lens equivalent of megapixels, superficially easy to understand and therefore the property most people think of first, but when taken on its own, far from being the whole story. The main panel of the widget is arranged in three sections; the menus are along the top, the main data display is in the middle, and the user controls and data readout are at the bottom. The desired focal length and aperture can be selected using either the mouse or the cursor keys (up/down to 'zoom', left/right for aperture). Using the cursor keys becomes especially useful when comparing two lenses. Below the main window are two further buttons, for full screen mode and permalink generation. Jump to: Widget Menus Sharpness and Chromatic Aberration Display Distortion Display Falloff Display Other Features How The Test Data is Shot Frequently Asked Questions

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