Step 3 Create an Adjustment Curve - to adjust the intermediate tonal values for an expressive print. 

Photographic emulsions react to light in a non-linear manner, taking a while to get excited, then gradually getting saturated and tired. Printing paper emulsions behave in a like manner and are engineered to compensate for the nonlinearity of the film sensitivity. If you present a perfectly linear grayscale to a paper emulsion, the results will be disappointing. The task, therefore, is to create a modification curve that will alter the tonal values of your perfect image to those expected by the paper emulsion you have chosen.


The target, I now prefer includes a step wedge and samples of the high value and low value bands from the target made in Step 1.

Differences between the silver print and ink jet print can then be estimated and corrections made to the curve. I prefer making adjustments to the curve with the Transfer Function in Photoshop, where changes can be made numerically.

Step A

Step B

Step C

STANDARD INK JET PROOF PRINT

Using the printer, paper, ink, AND printer settings chosen for ink jet proofing, print a test scale. These materials and settings should be EXACTLY the same as those that will be used to confirm the expressive quality of the images.

Performed only once to get a proof print to be used in the repeated executions of steps B & C.

INK JET NEGATIVE

Using EXACTLY the same procedures and settings determined for maximum black and perfect white in Steps 1 & 2, make a negative of the test scale. The first try may be WITHOUT any correction curve, or with the sample curve provided below.

Subsequent tries will use the curve as altered in response to the print comparison described below.

SILVER PRINT

Using EXACTLY the same materials, procedures and settings used to make a print with maximum black and perfect white in Steps 1 & 2, make a contact print with the test scale negative. Be sure to finish it EXACTLY as you will the final prints - same paper, developer, timing, toning, and washing aids if used.

 

After the silver print is dry, trim the edge as shown and place over the scale printed with the ink jet printer in step A above.

To reduce the effect of color and texture differences when viewing two different types of paper, I place a piece of Plexiglas over both and view the values with a Kodak WRATTEN No. 90 filter.

Estimate the change needed to bring each step of the silver print to the same value as the ink jet print. Shifting the silver print sideways may help asses the differences. For example, shifting the silver print to the left one space may show that the 20% value is close to 10% value of the ink jet print, indicating that the adjustment curve be altered to lighten the 20% value by nearly one step. There is no substitute here for experience and practice, although a densitometer or even a flatbed scanner will help.

THEORETICALLY (that is in capital letters!) If you get a silver gray scale that in indistinguishable from the ink jet proof scale, any silver images produced in the same manner will also be indistinguishable from their ink jet proof print. HAH! But they will be close and I have found that slight changes in the curve resulting from printing actual images, can serve to hone the curve to near perfection.

BUT! Remember the caveat in the section on image preparation. All I am saying here is that the silver print SHOULD match the ink jet proof. After viewing the silver print, you may decide to alter the actual image in Photoshop. Remember there is a perfect response curve for EACH image, which is precisely why some master printers try various papers and developers in the search for the perfect print of a given negative.


Adjustment Curve for the Epson Stylus Photo 1200

for Ilford Multigrade FB Paper
Zone VI paper developer (1:3)
3 minutes @ 20 deg, C

negatives to be printed with HUE=0
&

Transfer Function 100% value set to 70


When making adjustments to a the curve in the Transfer Function, the changes are being made to a 100 point percentage scale. After conversion to RED ink with the Color Table, the maximum density is only 56 percent. Although the photographic paper reacts to the color as well as the density, and the mix of magenta and yellow continually changes, altering the grayscale by one percentage point may not alter the final result by an equivalent amount. Some experimentation is necessary.


Start

Preparation

Step 1

Step 2

Step 4

Step 5

Image Preparation
Material Selection

Find Minimum Exposure Needed to Print Pure BLACK with the chosen negative material

Find Ink Combination
for the Proper "Effective Density" to Print Pure White.

Make a negative

Final Check

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