The lower the black point value and the higher the white
point value, the broader the tonal range your printing environment can
Be sure to read the
Printer Black Point section first since it contains useful background
Simply put, the white point is the point where the printer no longer lays
down any ink and lets the white of the paper represent white. A printer's
white point needs to be determined for every combination of paper, ink, printer,
print engine and printer profile you use. To keep track of your various
white points, you can print and use the
Printer Chart to record your white point values.
Figure 1. Printer White Point Target
The specific steps to determine the white point are listed here.
- Download the printer white point target from the
The download version will not have the word Sample printed across it.
- Do not apply any Photoshop adjustments to this file.
- Using the same process you use to print your images, print the target
for every combination of paper, ink, printer, print engine and printer
profile you use. If you use Photoshop, instead of a
RIP, to print your images, you may wish to review the
Photoshop Printing page.
- Let the target dry for at least 15 minutes. A day or two would be
better to allow the ink to cure and the solvents to dissipate.
- Using a strong light source, such as direct sunlight, look at the bottom
two rows. Looking at the target at an angle may help.
- The bottom two rows skip every other tone to make it easier to narrow in
on the white point. What you are looking for is the lightest tone that is
distinguishable from its darker tone neighbor but is indistinguishable from
(blends in with) all of its lighter tone neighbors. The higher the number,
the lighter the tone.
- Once you think you have found the white point, find this same tone in
the first three rows. The first three rows show tone in increments of one.
Fine tune which tone is the white point.
- Record this value on your
When printing your white point target, do NOT follow
Photoshop's instructions to print targets for custom profiles because that
is not what you are doing. Those instructions are for the printing of
a color target for the purpose of creating
a printer profile; not finding a white point value. Refer to
Printing page for how to print the white point target using Photoshop.
Figure 2. Since B is distinct from C but blends with A, B is the
Lets use Figure 2 to better understand what we are looking for. Figure
2 shows four tones: A, B, C and D. Tone D is easily distinguishable from
tone C. Tone C is easily distinguishable from tones B and D. Tone B
is distinguishable from C but not A. Therefore, given the definition that
a printer's white point is the lightest tone that is distinguishable from
its darker tone neighbor but is indistinguishable from (blends in with) all
of its lighter tone neighbors, then tone B is our white point. This is the
tone where the printing environment stops distinguishing between light tones and
resorts to not laying down ink.
If your printing environment laid down any amount of ink
for tone 254, then your white point is 255.
You only have to find the white point once for every combination of printer,
paper and ink. However, you have to apply a white point adjustment to
every image that has highlight detail you want printed. There are two
methods for doing this.
Figure 3. Levels Dialog Box. Only one of these is changed.
The customary method uses the Levels adjustment.
- Create a Levels adjustment layer by clicking Layer > New Adjustment
Layer > Levels. Or, by clicking the Create adjustment layer icon
at the bottom of the Layers panel.
- Change the Output Levels white value, 255, to the desired white point
- Click OK
- Change the adjustment layer's blending mode to Luminosity.
Once you make your adjustment, you will probably see a slight overall darkening
of the image. This is the tradeoff we give up in order to print the
details in the highlights. How much darkening appears depends on the white
point value. If the white point value is 250, there will be very little.
If the white point is 220, then you could see darkening past mid tone.
You can use a single Levels adjustment to apply both the
black point and the white point. Type the black point in the Output
Levels black value and the white point in the Output Levels white value.
Figure 4. Change the Output value to the white point value.
Figure 5. This Curves adjustment is available on the
The adjustment I prefer to use in setting the black and white points is a
Create a Curves adjustment layer.
- Click Layer > New Adjustment Layer > Curves. Or, by clicking the Create
adjustment layer icon
at the bottom of the Layers panel.
- Ctrl + Tab (Command + Tab) until tone 255 is highlighted. It is
highlighted when the small circle in the upper right corner becomes solid
black. Tone 255 has a red circle around it in Figure 4.
- When properly highlighted, the Input and Output boxes will be displayed,
both will have the value 255.
- Change the Output value to the white point value.
- Click OK.
- Change the blending mode to Luminosity to prevent any possible affect on
the image's color.
- Using black paint, paint in the layer mask so the texture-less highlight
areas will not be darkened.
Just like the Levels control, we can use a single Curves control to apply
both the black and white point adjustments.
- Download the Curves adjustment from the
- Create a Curves adjustment layer.
- With the Curves dialog box open, click the Load button.
- Locate the downloaded file and click Load. The curve should look like
- Ctrl + Tab (Command + Tab) until the tone 0 marker is highlighted. It
is circled in black in Figure 5.
- Type the black point value in the Output box.
- Ctrl + Tab (Command + Tab) until the tone 255 marker is highlighted. It
is circled in white in Figure 5.
- Type the white point value in the Output box.
- Click the Save button.
- Name the file so that it represents the printer-paper-ink combination
the adjustment is for.
- Click Save.
- Click OK to close the Curves dialog box and apply the adjustment.
- Using black paint, paint in the layer mask so the texture-less dark and
highlight areas will not be affected.
By saving this adjustment, you can reuse it for future images that are to be
printed using the same printer-paper-ink combination.