This is my first post. I have a zone VI variable contrast head, which I never felt did what it was suppose to do properly. I decided to do a series of BTZS paper test to determine once and for all if it was worth struggling with. The problem is that the there are three dials. One is for "soft"(green) and marked A-H,max,off. One is bightness marked 1-10. One is "hard"(blue) and marked A-H,max, off. There are too many possible settings (without exhausting a lot of time and materials)to test paper exposed at each possibility. I did a prelim.. at max blue/off green and max green/off blue on Ilford Multigrade IV-RC. The plotter program reads ES 0.70(paper grade 4.7) for max blue and ES 1.95(paper grade < 0) max green. The big problem comes with trying to choose which are the logical combinations of settings of the hard and soft letters that would yield useful data. I am a bit baffled because I tried "c" on soft with "h" on hard and got ES 0.90(paper grade 3.2) while I got ES 0.98(paper grade 2.8) with "a" on soft and "h" on hard. The "a" soft should provide less green light than the "c" soft and therefore should have in combination with "h" hard setting produced the more contrastly step tablet test. I believe that this why I have never been able to get consistent use out of this head because turning the dials intuitively up and down to get more or less contrast was not producing the desired color mix to produce the anticipated paper contrast. If anyone has any suggestion on how to set up a useful test scheme for the zone VI variable contrast head they would be greatly appreciated. This is the 4X5 head on Beseler MX chasis.