Digital BW, The Print

Mark - I would be careful about using that scale for ANY kind of reference.
They were made with offset lithography, meaning that there wasn't that much
ink put down on the cards, and the ink that is laid down is not very
lightfast.  If you've had a scale for any length of time, you'll notice that
after a while (especially if they have been exposed to a lot of light) the
grays don't stay neutral along the scale.  Some will be obviously more
magenta than others, etc.

I don't know how old the scale was that Joe was kind enough to measure, but
you might ask him if it showed any signs of aging.

These days the more standard reference for digital imaging tends to be the
Gretag color/gray scale chart (large and small are available, but they are
expensive) that is made with silk screen printing.  Much more ink is put
down on these cards, and they are relatively stable compared to the Kodak
ones.

Best,
Stephen Petegorsky