Signal to density mapping with controlled contrast

An image reproducing method comprising the steps of:

• (a) scanning a stimulable phosphor screen storing a radiation image with stimulating rays;
• (b) detecting the light emitted upon simulation;
• (c) converting said detected emitted light into a digital signal representation;
• (d) creating a gradation curve for mapping the signal values of said digital signal representation onto corresponding density values, said gradation curve being created by the steps of:
• (i) defining a canonical monotonical non-constant function Y(x) in an orthogonal coordinate system (x,y) between arbitrary values x.sub.0 and x.sub.1 and y.sub.min and y.sub.max ;
• (ii) determining minimum and maximum density values D.sub.smin and D.sub.smax ;
• (iii) determining minimum and maximum signal values S.sub.min and S.sub.max constituting a range wherein the gradation is defined by the canonical form and outside of which signal values will be mapped onto D.sub.smin or D.sub.smax ;
• (iv) defining the gradation curve as
• D(s)=D.sub.smin +(Y(x(s))-y.sub.min) . (D.sub.smax -D.sub.smin)/(y.sub.max -y.sub.min)
• wherein D(s) is the density in the reproduction as a function of the signal value s
• x(s)=x.sub.0 if s is smaller than or equal to S.sub.min
• x(s)=x.sub.0 +(s-S.sub.min).(x.sub.1 -x.sub.0)/(S.sub.max -S.sub.min) if s is comprised between S.sub.min and S.sub.max and
• x(s)=x.sub.1 if s is larger than or equal to S.sub.max
• (e) recording a hard copy image reproduction of said digital signal on a recording material utilizing said gradation curve to control density values in said hard copy image.