Digital BW, The Print

Since the densitometer I'm currently using 
> does not conform to any specific ANSI standards I don't think a 
> comparison of these values to ones from another densitometer would be 
> very meaningful.

Carl and Phil,

using a densitometer with standard density readings is essential if you are 
using IJC. In this case, the discrepancy in the results or readings between two 
different users would be made greater by non-standard instruments.

What you get with a non-calibrated instrument is still a smooth curve, i.e. when 
you plot your grayscale output it will make a smooth curve and that should 
help produce nice separation between steps etc.  But you'd be missing out (a) 
on achieving maximum density and (b) on proper overall gradation in parts of 
the scale. That would depend on the actual shape that you would get in  that - 
otherwise smooth - curve of the plotted densities. 

IJC is based internally on an ideal set of densities which it generates for a 
given dmax and paper white set of values. If you can't track those properly 
because of an out of whack instrument, you are simply missing some - but not 
all -  benefits of the system.

Antonis