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No matter how big your brain or how much you study, you still rely on your eyes to be able to see objects you need to describe. It all starts with your eyes. A similar principle applies to camcorders. All the Megapixels in the world cannot correct a badly resolved, low contrast, distorted image caused by a cheap lens. At Canon, we like to say that "it all starts with the
lens". Canon's six decade heritage of developing precision optics for its cameras cannot be counted in Megapixels. The commitment can be measured, however, by looking at the number of patents held by different companies in
Japan. Canon holds over 30% of all optical zoom lens patents – more than twice as many as any other camcorder or camera manufacturer. When you look through a toy telescope, you might describe the image as 'dull', 'fuzzy', 'woolly' or 'unclear'. When you look through a high quality astronomical telescope, you might use words like 'sharp', 'crisp' and
'clear'. The same would apply if you were to compare the output of a cheap camcorder lens with that of a Canon lens. Optical engineers use a number of measures to calculate lens quality. On all of these key measures, including contrast, resolution, MTF and aberration correction, Canon camcorder lenses consistently outperform competing
manufacturers. Contrast – the ability of a lens to reproduce the difference between light and dark. Video captured on a lens with poor contrast will appear life-less, flat and dull. Resolution – the ability of a lens to reproduce fine detail. It will be impossible to see fine detail – such as the letters on a sign – on video captured with a poor resolution
lens MTF – a function that shows the ability of a lens to maintain a good balance between contrast and resolution. Lenses with a good MTF function deliver both high resolution and high
contrast Aberration – the degree to which a lens introduces distortion and errors due to its inability to perfectly resolve light. There are many types of aberration that cheap lenses
commonly introduce, including spheric aberration (resulting in low contrast images and 'fringes' around light sources) and chromatic aberration (resulting in a 'rainbow' effect where light splits into its component colours). back
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