Stephen's post illustrates why I say it is important to follow your teacher.

He shows the two different calculations that come up with almost the same result.

1.2 NDR is the right target when working with the techniques described in "Way Beyond Monochrome," while I found 1.0 NDR to be the right target the way I work.


The Kodak Data Book, Kodak Papers (first 1955 printing), says you should select a paper with scale index 0.2 greater than the Density Scale of Negative and offers an explanation: "The reason for this appears to be that the method of measuring scale index takes into account the total available scale of the paper, while in practice it is desirable to use less of the extreme shoulder portion of the paper curve."

In the data book, Density Scale of Negative is effective density scale at the exposure plane so there is no doubt that you are left to figure out your own enlarger flare.

The data book gives a chart, keep in mind this is effective density scale:

Grade 2 paper, Scale Index 1.3, Density Scale of Negative 1.0 to 1.2

Further the data book says the densitometer would match a contact print. Diffuse enlarger lowers scale 10% or more, condenser enlarger with a diffuse bulb raises scale 15-25%, point source condenser maybe raises scale 60%