Digital BW, The Print

on 1/2/03 8:58 PM, Harry Saddler wrote:

> I bought a Kodak grey scale, to help me calibrate my quadtone curves. I
> got a 21-step scale, to match the 21-step stepwedges commonly used in
> quadtone work. But the "21-step" Kodak scale only has 20 steps! So:
> 
> 1. Why is a 20-step scaled called "21-step", and
> 2. Why 21 steps in the first place?

Good questions.

I'll venture a guess as to why 20 steps... 5% is a convenient denomination
and 20 is not too many and not too few steps.

I've no idea why they'd call it a 21 step wedge, unless it's similar to the
notion that the year 2001 was really the 2000th year since the birth of
Christ...(don't ask me to explain that, it's already ruined a few holiday
meals...)


Todd