Color Darkroom FAQ's & Tips

Tips

Getting Started Using Photoshop's Curves
A Note on Epson Printers
Soft Proof Your Pictures.
My prints appear darker (lighter) than on my monitor.
The colors in my Duotone prints don’t print properly.
Changing papers (inks, print resolutions) make my pictures look different.

FAQ's

Should I edit the Spot Colors or the Curves?
What if I don’t use Adobe Gamma to calibrate my monitor?
How do I uninstall Color Darkroom?

Tips

Getting Started Using Photoshop's Curves - 4/2003

1) Open an image in Photoshop (such as Color_Card.tif). Create a curves layer in Photoshop and adjust it so your screen emulates what your print looks like when using the unaltered color profile.
2a) Create a second curves layer and correct the problem.
2b) Note the input & output values of the adjustment points from step 2a.
3) Start Color Darkroom, open the curves dialog. Adjust the curves the same as in step 2.
4) Change the description of the profile, and do a "Save As", giving it a new file name.

This should get you fairly close on your color adjustments.
 

A Note on Epson Printers - 4/2003

Normally when printing, you should disable color management in the printer driver and let the color profile selected in Photoshop do all the work (see Epson's advanced settings in the print driver). Epson's canned color profiles seem to work best if you turn the color controls on, but set them to all to 0.

Soft Proof Your Pictures

"Soft Proofing" pictures on your monitor will give you an idea of what colors will look like on your printer. There's a cookbook on using Photoshop's proofing features that can be found at http://www.apple.com/colorsync/. Most printers use CMYK inks (some use other combinations) to create colors. All colors cannot be reproduced accurately. Proofing will give you an idea of what colors your printer can reproduce.

The website above also has some good information on color profiling, color models, etc. Note that Apple uses a system called "ColorSync" as well as ICC color profiles for color management. Although the system is somewhat different, the theory is the same.
 

My prints appear darker (lighter) than on my monitor.

There are two calibrations you'll have to do. First, calibrate your monitor. Next, calibrate your printer for each paper that you use. You shouldn't throw your monitor calibration off so that it looks like your print.

Monitor gamma settings effects the monitor's mid brightness and color casts. You want to see the colors that are really there in the picture data, and also have your printer match the screen. Calibrate the monitor first.

Perform the monitor calibration in the "Calibration" section of the manual. The grayscale wedge in ColorCard.tif shows shades of gray graduating evenly from black to white. If you have a professionally printed gray scale, use that to compare. After completing the monitor calibration and the grayscale on your monitor appears okay, go ahead and make adjustments to the printer profile as needed.

Since this is an overall adjustment, use the Curves editor in CD. Place cursor at 128. Set the Q to 4 or 5. Select all 3 colors (R, G, and B) for adjustment and increase (or decrease) the output accordingly. (see "Getting Started Using  Photoshop's Curves")
 

The colors in my Duotone prints don’t print properly.

Perform the Grayscale Setup as described in the Calibration section of the manual (see "Getting Started Using  Photoshop's Curves"). Make a copy of your grayscale profile and proceed to the Duotone example, also in the Calibration section.
 

Changing papers (inks, print resolutions) make my pictures look different.

You'll need a different color profile for each paper and ink (if using different manufacturer's inks). Different papers and inks will have a different look. Start with the manufacturer's canned profile and do the grayscale calibration. Make the adjustments in the Curves (see "Getting Started Using  Photoshop's Curves").

FAQ's

Should I edit the Spot Colors or the Curves?

Spot Color editing is mainly for correcting problems with specific colors (logos, Duotone colors, etc.). Changes to Spot Colors only effect the color you are editing. Other colors will not be effected. Edit Spot Colors when correcting "rainbow colors" in the grayscale (changes over a small range of luminance points).

The Curves are for correcting the overall color balance and grayscale. If you've changed papers, inks, or print resolution, edit the Curves.

Start by opening your grayscale calibration and create a new profile for the specific case using Save As.

(1) "Rainbow Colors" refer to color variations over a small range of luminance, typically less than 10 luminance points.
(2) See "My prints appear darker (lighter) than on my monitor" below.

What if I don’t use Adobe Gamma to calibrate my monitor?

If you use other software to calibrate your monitor, follow their directions and skip the monitor calibration section. Check to see that the grayscale in Color_Card.tif appears to display normally.

If you are using other monitor calibration software: In Windows, check that "Adobe Gamma Loader" is not in your Start | Programs | Startup group. If it is, delete it and restart your computer.

How do I uninstall Color Darkroom?

In Windows, click Start | Settings | Control Panel. Select Add/Remove Programs. Color Darkroom should appear in the list. Proceed and remove the software. Color Darkroom creates the file "ColorDarkroom.dat" the first time you run the program. This file is located in Photoshop's Plug-Ins\Filters folder. You will have to delete this file manually. You also have to delete the installation file that you downloaded.

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