A few years ago, I met an executive from a large camera company. Before digital photography came along, this company’s marketing (and manufacturing) emphasis had been on the quality of their lenses. This is  subjective field – you can use focal length and aperture as a proximate measure, but no serious photographer would equate a “no-name” lense with the same metrix with a lense from a well-known manufacturer.

And you know what? It was broadly right – a good lens meant a better photo.

Then the digital camera came along – and now people buy cameras based on one simple metric: the number of megapixels. This is not really correlated to image quality for most people (unless you want to print a photo to cover a bus shelter). But it allows consumers to compare products using a nice, simple metric – camera x has 12 megapixels for $200, camera y has 15 megapixels for $200 – camera y is the best deal”.

The camera executive called this phenomenon “the tragedy of the mega-pixel” – he said his company culture had changed. The focus on lens quality was still there – but it wasn’t commercially meaningful in the short term. When it came to dollars, it was better to invest in mega pixels than glass.