Untitled Document

Piezography BW Correctly Printing the 21 step test strip
Please report errors or omissions to Bill Bergh - bill@cone-editions.com

We have provided a greyscale 21 step strip on the PiezographyBW CD disk to assist users with calibrating their monitors using the procedure in the PiezographyBW manual on the CD disk. There are 21 numbered boxes in 5% increments from white (0% black) to black (100% black).

This file is also helpful in trying to diagnose problems when printing, or when calling for help with tech support.

Problems may occur printing the 21 step greyscale that will skew the tonal range of the image. If this happens, it can lead to a wrong diagnosis of a problem - or suggest there is a problem when there really is none.

Because this was a reference file, it should never be changed or saved during a Photoshop session. Applying a curve or levels change to the file, will of course make the 21 step strip print differently than intended. The file needs to stay the same to insure integrity of print results at different times. Most people understand this, and the most common mistakes are things that happen behind the users back, that they may be unaware of.

PROBLEMS
1 - FILE WAS CONVERTED WHEN OPENING
2 - FILE WAS MODIFIED WHILE OPEN IN PHOTOSHOP
3 - FILE WAS MODIFIED WHEN SAVED IN PHOTOSHOP
4 - HOW TO TEST THE INTEGRITY OF THE TEST FILE

1 - FILE WAS CONVERTED WHEN OPENING.

This problem is caused by the Photoshop default settings. The image data may be transformed to an embedded profile, or to a working space, to some default dot gain setting. Either will change how the image prints.

RECOMMENDED GREYSCALE SETUP FOR PIEZOGRAPHY

Photoshop 5.0 and 5.5
1 - Click on "File" -> "Color Settings" -> "Profile Setup"

2 - Under the heading "Assumed Profile" set "Greyscale" to "None".

3 - Under the heading "Profile Mismatch Handling" select the option "Ask When Opening"

4 - By setting the default settings in Photoshop in this manner - a warning box will appear when ever a file is opened, and there is a mismatch. In the "Profile Mismatch" warning box, ALWAYS click "Don't Convert".

Photoshop 6
1 - Click on "Edit" -> Color Settings"

2 - Under the heading "Color Management Policies" set "Grey" to "Off" and check the three check boxes for "Profile Mismatches", "Missing Profiles", and Ask When Pasting".

3 - By setting the default settings in Photoshop in this manner - a warning box will appear when ever a file is opened, and there is a mismatch. In the "Embedded Profile Mismatch" warning box, ALWAYS select the "Discard the embedded profile (don't color manage)".

2 - FILE WAS MODIFIED WHILE OPEN IN PHOTOSHOP
Do not apply any adjustment curves or levels or modify in any way, a reference file such as the 21 step strip. This kind of file is intended for testing and comparing the results to tests conducted at a later time.

3 - FILE WAS MODIFIED WHEN SAVED IN PHOTOSHOP
A reference file should never be saved for any reason. There was no reason for it to be modified in the first place. Always select "Don't Save", if this box pops up.

4 - HOW TO TEST THE INTEGRITY OF THE 21 TEST FILE
The "Eyedropper" tool Photoshop is very useful for checking the black percentage levels of any image. To set up the Eyedropper tool to work as a densitometer do the following:

EYEDROPPER TOOL SETUP

Photoshop 5.0 and 5.5
1 - Make sure the Options Palette is visible. If you cannot see the Options palette, click on "Window" -> "Show Options".

2 - Double click the Eyedropper tool in the tool palette. The Options palette will now display "Eyedropper Options". Select "Point Sample" instead of 3x3 or 5x5 Average".

3 - Make sure the Info Palette is visible. If you cannot see the Info palette, click on "Window" -> "Show Info".

4 - Make sure that one of the readouts in the Info palette displays the "K" reading. If you do not see a "K" readout - click on the small triangle at the upper right corner of the Info palette window. This will pop up the "Palette Options" box. Change one of the two "Readout" modes to greyscale.

Photoshop 6
1 - Click the Eyedropper tool in the tool palette. The Eyedropper options are displayed at the upper left of the screen in the tool options bar. For the Sample Size, select "Point Sample" instead of 3x3 or 5x5 Average".

2 - Make sure the Info Palette is visible. If you cannot see the Info palette, click on "Window" -> "Show Info".

3 - Make sure that one of the readouts in the Info palette displays the "K" reading. If you do not see a "K" readout - click on the small triangle at the upper right corner of the Info palette window. This will pop up the "Palette Options" box. Change one of the two "Readout" modes to greyscale.

USING THE EYEDROPPER TOOL AS A DENSITOMETER
Move the eyedropper around the image and watch the info palette "K" readout. This will display the percentage values of the pixels from 0 to 100%. Make sure that the 21 step boxes are incrementing in 5% steps. If they are any other value, then the image has been transformed somehow and will not print correctly. Close the image and reopen the source file from the disk or download a new copy from the web.