Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "zonepeter" <zonepeter@a...> wrote:
> 
> My densitometer arrived today without calibration plaques.  I have a 
> Kodak Q60 (IT8) reflection target.  I was able to locate a web site 
> with densities for the gray scale on the bottom, including averages 
> for the d max and d min from 16 different charts they had tested.  
> I used these values and calibrated the densitometer.  Based on this, 
> I am getting readings that seem reasonable.  (EEM 1.64 dmax and HPR 
> at 1.72)  
> Is this a fairly accurate way to go or should I bite the bullet and 
> buy the calibration plaque.  I will be using the densitometer to 
> build curves with QTR or IJC/OPM.

Is your densitometer an X-rite?

My X-rite 414 (status A) needs a cal plaque with a d-max around 1.8. An X-rite status A cal plaque only has white, black, and gray spots. The black is 1.8. If you try to cal it with something around 1.6, it actually decides it's a status E, status I, or status T instrument (I am not making this up) and the firmware goes into status E/I/T mode. Cal then demands you meter the magenta, cyan, and yellow spots of the plaque for a status E/I/T instrument. And the ned result is a really messed up, non-linear instrument.

It took hours on the phone with x-rite tech support to get this resolved.