Is it magic, or what?

just wondering ...... how does one get a 16 bit tiff out of a 12 bit raw? How can that be possible.....I have been shooting raw for a long time now, then converting to 16 bit tiff....but how exactly does that work?

anyone care to enlighten me? Thanks.

Wojtek

Yeah..the tiff is capable of 16 bit color depth, but you are actually only using 12 of them.

It's sort of like a refridgerator. It's never full, but you *could* fill it. There's a lot of empty space in a fridge, and 4 bits of the 16-bit TIFF are unused.

Note that by the time you are done editing in Photoshop/whatever then you might actually be using all 16-bits, or at least more of them. Adjusting levels and contrast and color balance will probably "spread" the data out more and will probably use some of those previously "empty" bits.

So it's sorta like going grocery shopping and putting more stuff in the fridge.


Obviously I need more coffee.

Actually you need 16 bit tiffs to keep all the info present in 12-bit RAW files, because of the gamma correction. RAW files have a 1.0 gamma (known also as a linear gamma), and "normal" images use a nonlinear gamma of 1.8 or 2.2, so to "pack" all the highlight information to a 1.8 gamma without loosing values, 16-bits are needed. Of course in the midtones and mostly in the shadows there is a lot of unused extra space, and that´s why some people recommends to shot as near highlight clipping as possible, because due to the linear gamma half of the total range of values are in the last brightest stop.

I don't think this is a matter of coffee. My first guess is: You are hungry and there is something missing in your refridgerator.