"Pixel count aside, one of the more interesting advances coming to market in the wonderful world of digital imaging would have to be the jump to 14-bit color (up from 12-bit color) in several of the newer DSLRs. And if you do the math, you know this is more than a 2-bit improvement.
"In a break from the pack, Canon's EOS 1Ds Mark III, 1D Mark III, 40D, along with Nikon's D3 & D300 have the ability to capture 14-bit RAW image files, which have the potential to produce up to 16,384 shades of gray. Most all other 35mm-based DSLRs currently feature 12-bit capture, which can reproduce 'only' 4067 shades of gray, which in itself isn't too shabby if you consider JPEGs, at 8-bits, contain a maximum of 256 shades of gray regardless of how they were originally captured.
"These numbers can be misleading at first, because an 8-bit image can contain up to 256 shades of red, 256 shades of blue, and 256 shades of green. And when you multiply 256 x 256 x 256 you end up with a total of 16.7-million possible colors from your average JPEG. The newest Canon and Nikon DSLRs (along with Mamiya's ZD medium-format back), capture images in 14-bit color, which has the potential of reproducing up to 4-times the volume of tone of the average 8-bit file.
"And in case you're wondering what you get for a digital camera that costs as much as a tricked-out Mini Cooper S, Hasselblad's H3D-series medium-format cameras capture images at 16-bits, which works out to 65,536 shades of gray, which when multiplied by itself three times over (RGB) comes out to 281 trillion colors… give or take a few billion if it's overcast.
"Now the human eye can 'only' differentiate between about 500 shades of gray – or about 7 to 10 million colors - and the finest desktop printers cannot come anywhere near reproducing this volume of tone and color. Magazines? They're on par with entry-level laptop printers, which actually aren't all that bad nowadays. So at the end of the day, what's the big deal?
"Perhaps the big deal can best be illustrated by examining the histogram of the last JPEG you tweaked in Photoshop. What probably started off looking like a peaked mountaintop bordered by diminishing hills and valleys suddenly became a jagged, comb-like graph with major gaps of image data visibly missing as a result of diddling around with Curves, Levels, and other tonal adjustments.
"The same image captured in 14 or 16-bit color, which starts out packing far more image data than the 8-bit economy model, can survive most any adjustments you make and come out the other end with nary a hint of data loss on the resulting histogram. Even after conversion to 8-bit color, the resulting image remains far more robust with smoother tonal transitions than a comparable file that started out in an 8-bit color space."
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