Diary entry 21st November 2008
Steve is over for the weekend. His wife has taken the kids to her mother's, and
he fancied some time with his old mates. Although I'd other things planned, he
nags me to go with him to Tottenham Court Road to see what
laptops are selling, which is one of his ways of keeping abreast of trends. I take
a camera because I know he'll want me to snap any designs that catch his eye.
There’s a particularly slim Korean pc he has me photograph from every angle
until we’re thrown out of the store by a security man. On the bus home he’s
ranting about 'the Koreans stealing a march on us', and begs me to show
him the pictures on the Leica. Although we’re sitting right under a
light at the back of the bus, the pictures are bright and clear on the preview
screen. Steve forgets about the Koreans for a bit and says 'Wow those pictures
'So they should be', I say, 'the camera's twenty thousand bucks, and
they're sixteen megapixel pictures.'
Steve's got money coming out of his ears, so he ignores the price of
the camera, but the pixel count gets to him. 'Sixteen megapixel? Wow!' He
snatches the camera out of my hands. 'How do they get sixteen megapixels in a
display like that?' and he lifts his specs to peer at the little screen at the
back of the Leica.
I grab the camera back before he breaks it and say: 'Don't be daft. It's the pictures that are sixteen meg, not the screen.'
Steve gives me that old familiar look that tells me he's lost, so I explain
that the number of pixels in the screen is less than the number in the picture,
and I tell him a bit about dithering and the other techniques in the algorithms
that map the larger picture to the smaller display, and so on, but being a big
picture man he asks 'why don't they just make a 16 megapixel
'Because it would be pointless,' I say. 'The eye can only see so much detail.
As you increase the pixel density you reach a point at which it exceeds the
resolving power of the retina.’
‘Gee I never thought of that,’ Steve says. I stare at the ceiling of the
bus, and blow a deep frustrated breath through my nose. Who’d believe it?