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Date

Re: New 400 T-Max Film

Fred Newman

9:23 2 Jun 08

Paper ES shift

Randy

6:33 30 Jan 08

I know someone in this forum will be able to educate me on what I'm missing here.
I bought a used Devere 5108 8x10 enlarger that has a close loop color head. Within the available programs there is a VC program that adjusts the head in 1/2 'grade' increments for BW VC paper.
So I took my Ilford multigrade paper, made a series of step wedges, read them on the densitometer and plotted them. So far so good .I can get mid grade 0 to high grade 4 in fairly even steps.
So using the probe on the CLS I determined the reading and time that would give a 90% ID max with each grade and off I go.
Heres where the confusion starts. I know from my first run to plot the grades that the grade 2 setting produces an actual grade 2 with an ES of 1.05. When I then use the same step wedge to make the first step 1.84 (2.04 x.90) by adjusting expose, and I plot that test in plotter, it tells me that the paper has an ES of .90 and its a grade 3? I can't find anything in the plotter books or help topics that address this.
I suspect its because I'm loping off the toe of the curve by starting at 90% of ID max, but I'm still uncomfortable with that assumption.