The lower the black point value and the higher the white
point value, the broader the tonal range your printing environment can
If you are unfamiliar with the Photoshop Levels and Curves controls, it is
suggested you read the Levels section
Curves section before continuing.
The ability of monitors to display detail in shadow areas is usually better
than a printer's ability to reproduce them. Therefore, there is the
possibility of seeing detail on a monitor that, when printed, prints as a solid
black or a very dark gray.
Lets assume Figure 1A represents the tones found in an image. Tone A is
the darkest tone, B is the next darkest, then C and then D. As shown in
Figure 1A, Photoshop (and a good monitor) can distinguish between the four
tones. However, a printer is not as fortunate. Many printers have a
difficult time reproducing subtle differences in the darker tones. Figure
1B represents how the same image might be printed by a printer. As we can
see, tones A and B blend together. We cannot tell where one begins and the
Figure 1A. What Photoshop sees
Figure 1B. What your printer sees
The tone at which the printer can no longer distinguish between it and the
next darker tone is known as the black point. For critical printing, it is
important to know where this transition is so we can bring the detail up into
the tonal areas the printer can handle. To accomplish this requires two
Step one is to determine where the printer no longer prints discreet dark
tones. This step is not performed for every image. It needs
to be done only once for every combination of paper, ink, printer, print engine
and printer profile you use. The second step is to manipulate the image's
tonal range so shadow detail will print. The second step has to be done
for every image that has shadow detail you want printed. This topic covers
Detail and sharpness are not the same thing.
Sharpness is how crisp edges are in an image. Detail is perceived
texture. Whether or not the detail is in focus is irrespective of a
printer's black point.
The ability of a printer to print detail in the shadow areas of an image is
dependent on more than the mechanical components of the printer. It is
also dependent on the ink being used, the paper being printed on, the software
(print engine) used to do the printing and the
device profile used by the print engine (not the profile embedded in the
image). For more on device and image profiles, you may wish to read the
A printer's black 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 black points, you can print and use the
Printer Chart to record your
black point values.
Figure 2. Printer Black Point Target
The specific steps to determine the black point are listed here.
- Download the printer black point target from the
Downloads page. 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
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 black point. What you are looking for is the darkest tone that is
distinguishable from its lighter tone neighbor but is indistinguishable from
(blends in with) all of its darker tone neighbors. The lower the number,
the darker the tone.
- Once you think you have found the black 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 black point.
- Record this value on your
When printing your black 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 black point value. Refer to the
Photoshop Printing page for how to print the black point target using
Figure 3. Since B is distinct from C but blends with A, B is the
Lets use Figure 3 to better understand what we are looking for. Figure
3 shows four tones: A, B, C and D. Tone D is easily distinguishable from
tone C. Tone C is easily distinguishable from tone B. Tone B is
distinguishable from C but not A. Therefore, given the definition that a
printer's black point is the darkest tone that is distinguishable from
its lighter tone neighbor but is indistinguishable from (blends in with) all
of its darker tone neighbors, then tone B is our black point. This is the
tone where the printing environment stops distinguishing between dark tones and
resorts to printing solid black.
Reading the actual printer black point target is a lot
harder than the A-B-C-D example you see here. Reading the target in a
strong light will help. Also, you will find the black point for matte
paper and glossy paper will not be the same.
You only have to find the black point once for every combination of printer,
paper and ink. However, you have to apply a black point adjustment to
every image that has shadow detail you want printed. There are two methods
for doing this.
Figure 4. 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. Figure 4 shows a Levels dialog box.
We need to change it so our darker tones are remapped based on the black point
value we determined above. However, I am not going to tell you how to do
this (at least, not at first). You are going to tell me.
I will give you a couple of hints first.
- The value that needs to be changed is either the Input Levels value
highlighted in red or the Output Levels value highlighted in red.
- Input Levels is used to remap what tone in an image is solid black (tone
0). If changed to, for example, 21, then Photoshop will remap the darker
tones so tone 21 becomes solid black. Output Levels is used to remap what
tone in an image is the darkest tone allowable in the image. If changed to
21, then tone 21 becomes the darkest tone allowed in the image and Photoshop
will remap the darker tones so no pixel is darker than 21.
So, which value do you think we need to change? The Input Levels value
or the Output Levels value? Once you think you have the answer, click
below to see if you are correct.
- My answer is to change Input Levels
- Sorry. In images with shadow detail we want printed, we need to
tell Photoshop the black point is the darkest tone in our image.
This is not the same as telling Photoshop to remap our black
point to solid black. If we used Input Levels, we would actually
compound our problem by moving shadow detail into even darker
tones. What we need to do is move shadow detail into the lighter
tones the printer can reproduce. You may wish to review the
Levels Output page.
- My answer is to reset Output Levels
- Yes! You are correct. By typing the black point value as the
Output Level, you are shifting shadow details into lighter tones the
printer can handle.
Once you apply the adjustment, change the adjustment
layer's blending mode to Luminosity.
Once you make your adjustment, you will probably see a slight overall
lightening of the image. This is the tradeoff we give up in order to print
the details in the darker shadows. How much lightening appears depends on
the black point value. If the black point value is 5, there will be very
little. If the black point is 30, then you could see lightening all the
way into Zone VIII. This is why I prefer the Curves Method instead of the
Levels method when my black point adjustment causes a major shift in contrast.
Remember, we are only trying to shift the dark details into tones the printer
can handle, not change the overall contrast of the image.
Figure 5. Change the Output value to the black point value.
Figure 6. A large adjustment will reach into the middle tones
Figure 7. Anchor points can isolate the change
Figure 8. Layer Mask
The adjustment I prefer to use in setting the black and white points is a
Create a Curves adjustment layer by clicking Layer > New Adjustment Layer >
Curves. Or, by clicking the Create adjustment layer icon
at the bottom of the Layers panel. Figure 5 shows a Curves dialog box.
We need to change it so our darker tones are remapped based on the black point
- Ctrl + Tab (Command + Tab) until tone 0 is highlighted. It is
highlighted when the small circle in the lower left corner becomes solid
black. Tone 0 has a red circle around it in Figure 5.
- When properly highlighted, the Input and Output boxes will be displayed,
both will have the value 0.
- Change the Output value to the black point value.
- Click OK.
- Change the blending mode to Luminosity to prevent any possible affect on
the image's color.
Since Levels and Curves are non-linear controls (a change in dark tones will
gradually taper off to where the lighter tones are not affected), the closer a
tone is to the black point the more it will be affected. Even though this
is exactly what we want in order to bring shadow detail up into lighter tones
the printer can handle, if the black point value is large enough, then a fair
amount of the image could be affected.
Figure 6 shows an adjustment for a black point of 34. (Yes, I actually do
have a 100% rag, matte paper whose black point is 34.) The red line shows
the default curve, the black line shows the adjusted curve and the green area
shows how much each tone is being changed. As you can tell, the affect
tapers off the closer you get to white (upper right corner). However, the
affect goes well into the middle tones and beyond.
How do we isolate our black point adjustment to just the areas we want?
This is where anchor points on the Curves control come in. And this is the
very reason why I like to use Curves to make this adjustment.
Figure 7 shows the same adjustment, but with anchor points. As you can
tell, even with a large black point, only Zones O through II are being affected
while Zones III through X are unaffected.
You can add the anchor points yourself, or you can download a Curves black/white
point adjustment, with locking anchors already in place, on the
I often find when I apply the black point adjustment, using either Levels or
Curves, certain dark tones with no detail become lighter than I would like and
they lose their richness. The solution to this is a layer mask. If
you used an adjustment layer to apply the Levels or Curves black point
adjustment, activate the layer mask by clicking on the layer mask thumbnail in
the Layers panel. See Figure 8. Then type the letter d to set the
default foreground colors to black and white. If black is not the
type the letter x once. Then use an appropriately sized brush to paint in
the layer mask (not on the image) to block these tones from being affected by
the adjustment. Areas painted black will not be adjusted. Areas left
white will be adjusted.
Remember, only mask out the dark areas
without detail. Do not mask out the dark areas with detail.
Since a black point is dependent on the combination of paper, ink, printer,
print engine and printer profile, there are no hard and fast black point values.
(If there were, we would not have to find our own black point values.)
However, you may encounter a situation where the black point value seems too
high. Using Epson printers as a guide, generally you can expect black
points for glossy and luster papers to be in the single digits to the mid teens.
For matte papers, it may go all the way into the low 30s. If you get
unusually high black point values, you may wish to check the following.
They are in order of most likely to be the cause, to the least likely.
- Are you using an ICC profile in your printing steps? If you are using
Photoshop, and not a
RIP, to print your images, review the
Photoshop Printing page to be sure you are following the proper steps to
print your image.
- Are you using a custom ICC profile for the specific paper and ink being
used (and not a generic profile)?
- Are you using quality paper and the printer manufacturers ink
- Does the printer pass the head alignment and nozzle checks?
- Are your ink cartridges out of date?
- Are you reading the printed target correctly? The difference you are
looking for is very, very subtle and will be hard to spot (unless you have
jet fighter pilot eye sight). If the black point value you are deciding
upon has an obvious difference to its lighter toned neighbor, then you need
to look more closely.
- Get a second opinion. Someone with better eyesight might find a lower
- Very unlikely, but possible, there could be something wrong with the
printer. If you can get a low black point using glossy paper, then it is
By using a Curves adjustment layer with anchor points and a layer mask, we
can print our shadow detail, and dark tones with no detail can remain unchanged
in order to retain their deep, rich color.
Question. I have an image whose tone is fairly evenly
distributed from dark to light and when I apply the black point compensation to
my image, the overall image gets lighter.
Answer. This usually happens when the black point adjustment is a
high number and the adjustment is made via Levels or a straight line Curves
adjustment. Apply your adjustment using a Curves adjustment layer
utilizing anchor points that lock the mid tone and highlight areas in place.
What we are trying to do is bring those dark areas with detail into the range
the printer can handle. There is no need to shift the mid tone or
highlight areas. However, if Levels or a straight line Curve is used, more
than the dark areas will be affected.
Remember, a Black/White Point Curves adjustment, with
anchor points in place, is available on the
Question. I applied a black point adjustment to my image, but
the dark areas just became a muddy gray. I liked it better without the
Answer. When you apply a black point adjustment, we are shifting
dark areas into lighter tones so the printer can reproduce the detail in the
dark areas. If there is no detail, then the dark areas will become lighter
and not look as rich. I always apply my black point adjustment using a
Curves adjustment layer with a layer mask. At first, the layer mask is
solid white. Once I apply the adjustment, I zoom in on the dark areas.
For those dark areas without detail, I paint in the layer mask using black
paint. This blocks the adjustment from this area. Be sure you paint
in the layer mask and not on the image itself. (Sometimes this is easily
missed since we are masking dark areas.). Please read the section Dark,
Texture-Less Tones above.