Come along with
me as I calibrate an Epson Pro Cinema 1080p projector using the new Sencore
OTC1000 ColorPro Color Analyzer and Sencore VideoPro generator. You'll see
the simplicity of the Control Calibration Center within the CP6000 software
as it guides us through each step. Keep in mind other displays are similar
so the process you use will be pretty much the same.
OTC1000 Calibration
Setup
To
get started we need a few simple connections. Connect the OTC1000 sensor to
the laptop, using the supplied USB cable. If the New Hardware wizard comes
up, follow directions through the wizard. The OTC1000 does not require an
additional USB driver; it is automatically recognized by the software as a
standard human interface device (HID).
Connect
the VideoPro output to the projector, using the video input normally used
by the projector. Connect the video generator's serial port to the laptop,
with the provided null-modem serial cable. This permits the ColorPro 6000
software to control the video generator. In case your laptop does not have
a serial port, a USB to serial adapter is included with the OTC1000 ColorPro
Color Analyzer.
With
all connections complete, click on the ColorPro 6000 icon to launch the ColorPro
6000 software. During initialization, a dark calibration box appears prompting
us to place the lens cap over the OTC1000 lens for dark calibration. With
the lens cover in place, initiate dark calibrate. Upon completion, the software
opening screen appears. Remember to remove the lens cap!
Figure
1. Typical
setup used to calibrate the Epson projector; using the Sencore OTC1000,
VideoPro Generator, and CP6000 software.
The Calibration
Control Center
The
opening software screen presents a Calibration Control Center tab. Click on
this tab to select it. The Calibration Control Center provides a guided 10-step
process, resulting in a complete calibration including report documentation.
In the Calibration Control Center page we see the ten tabs, starting with
Customer on the left, to Calibration Report on the right. To perform a complete
Epson 1080p calibration with report documentation, we'll simply progress through
each of the tabs/steps from left to right starting with the Customer
tab (1).
Figure
2. The
Calibration Control Center provides a guided 10 step process, resulting
in a complete calibration including report documentation.
Step 1: Customer
To
add a new customer, click the New button on the Customer page. Fill out the
customer information as completely as you want the information to be printed
on the final calibration report. When finished, select the Display tab to
move to the next step (2). Hint: This step creates a file in the software
database in which calibration information is stored.
Figure
3. Click
the New box to create a new customer. Enter the customer
information as you want it shown on the calibration report.
Step 2: Display
On
the Display page we'll click on the New Session box to create
a new calibration session. Fill out the information as you want it to appear
on the final calibration report. Work your way down the list of display documentation
items. The three asterisked items are mandatory. The other entry items are
optional, but do appear on the final report.
Figure 4. Click on the New
Session box to create a new session. Fill out the information as
you want it to appear on the final calibration report.
The
bottom of the Display page contains a control section for the VideoPro generator.
To configure the video generator, we click the Generator Setup button and
verify that we are set up correctly for the video signal type and format that
we wish to feed the display. At this point we have a picture on the display
and are ready to start so we click on the Pre-Calibration Capture page (3).
Step 3: Pre-Calibration
Capture
The
Pre-Calibration step documents the "as is" settings of the display's control
settings and performance including gamut, white balance and gamma. Upon selecting
the Pre-Calibration Capture tab, the User Control Setting entry blanks and
White Balance Controls entry blanks are shown. Enter the values of these controls
so they show the 'before calibration' settings in the final calibration report.
Setting up
Ambi-Block™
Before
clicking the Capture box to capture pre-calibration performance, we should
consider any ambient light in the room. If there is light in the room, we'll
turn off lights if we can or close window blinds/curtains. Remaining light
can be eliminated from measurements by using Ambi-Block. Ambi-Block measures
the ambient light and subtracts it out of the measurement.
Eliminate
as much room light as possible and completely block the projector lens to
eliminate projector light. Do not set the projector to black as some light
is still emitted to the screen.
1.
Press the Ambi-block button (bottom right corner on CP6000). The Ambi-Block
setup window appears.
2.
Select the Enable Ambi-Block check box.
3.
Click the Ambi-block Capture button; Luminance and Chromaticity measurements
are filled in.
4.
Click OK on the Ambi-Block setup window.
5.
Unshutter or unblock the projector lens.
Figure 5. Ambi-Block measures the
luminance and chromaticity of any ambient light falling on the projector
screen, then subtracts the effects of that ambient light from subsequent
projector measurements.
Capture Pre-Calibration
Display Performance
After
documenting all the pre-calibration settings and setting up Ambi-Block, we
are ready to capture the pre-calibration performance of the display. Click
the Capture button to begin taking measurements for the pre-calibration report.
After we click the Capture button, the Crosshatch pattern is displayed. Press
the Laser button on the OTC1000 and aim the ColorPro at the center of the
pattern. When the probe is aimed, click the Next button and the measurement
progress bar will work its way across. When the wizards are done, click Finish.
Proceed to the Preset Image Levels page.
After
you have documented all the pre-calibration settings that you want to, and
have set up Ambi-Block if desired, click the Capture button to begin taking
measurements for the pre-calibration report.
Figure 6. The Pre-Calibration step
documents the "as is" settings of the display's controls and the display's
performance including gamut, white balance and gamma.
Step 4: Preset
Image Levels
Once
the pre-calibration performance of the display is captured, it is time to
start calibrating. The Preset Image step presets the brightness (black level)
and contrast (peak white level) for the display. This sets up a proper video
dynamic range prior to any calibration adjustments. Click the Preset Levels
button, and the Preset Image Levels wizard will come up. Click Next to advance
to the Black Level adjust step, displaying the Pluge pattern.
Figure 7. The Preset Image Levels
step guides us through presetting the brightness and contrast controls of
the display.
To
set the black level, we'll adjust the brightness so we are just able to see
the outside box flashing, as the ColorPro software shows us. On the Epson
1080p projector, the black level is clamped to an absolute level, meaning
we are unable to see blacker than black signal levels in the picture. When
finished, we'll click the Next button to advance to the Preset White Level
step using the HiLoTrk pattern.
Figure
8. The HiLoTrk Pattern is used for
presetting contrast. Both lower boxes
in the center should be visible.
We
use the display's contrast control to preset the white level. When viewing
the bottom center half of the HiLoTrk pattern, we increase the display's contrast
control to a level that causes the larger box to disappear into the white
surrounding it, then we back off the control a couple steps before the disappearing
point. When finished with the contrast setting, we'll click the Next button
to proceed to the Test Gamma Settings step.
Step 5: Test
Gamma Settings
This
step tests the gamma performance of this projector, to determine which of
the projector's gamma settings is most desirable. The Epson 1080p has several
gamma settings found in the user menu under Image, Advanced, Gamma. We'll
select one of the settings and click Capture to measure the projector's gamma
performance with that setting. When the first measurement capture is complete,
a red line is plotted on the graph, depicting the gamma for each IRE level
tested.
Figure 9. Test Gamma Settings plots
the gamma test results from each of the projector's gamma selections to
determine which setting is most desirable.
Step 6: Adjust
Color Gamut
The
Epson Pro Cinema 1080 has color management saturation and hue controls to
adjust the exact colors of the individual primary/secondary colors. The ColorPro
6000 software has provisions for adjusting these settings. If a display doesn't
provide color management adjustment, we simply skip this step.
Under
the reference drop down box, we select the red reference and the projector
displays a pure red field. We press the Start button on the bottom left of
the software to begin measurements. The controls that we are going to adjust
are found in the Epson user menu, under Image, Advanced, RGBCMY.
Figure 10. The Adjust Color Gamut
page makes it easy to adjust the individual colors of a display's primary
and secondary colors, when color management controls are provided on the
display.
Note:
the ColorPro 6000 software provides configurations for both NTSC and HDTV
color systems. The software installs with NTSC selected by default. If we
wish to adjust to HDTV color gamut, we need to change the Color System Standard
to HDTV. To change this setting, go to Setup, Preferences, and under Color
System Standard, select the appropriate setting.
Make
sure that the OTC1000's laser measurement circle does not include the projector's
user menu, as that will throw off the measurements. Once the probe is aimed,
we see a black measurement dot on the CIE Target, in the lower right. Using
the Hue and Saturation controls, we steer the black dot as close as possible
to the center of the target. When finished with red, we move on through each
of the other colors. When finished, we'll proceed to the Adjust White Balance
page.
Step 7: Adjust
White Balance
We
click the Start button, at the bottom left corner of the software, to start
making measurements. We select the high IRE window, under Generator IRE Control,
and adjust the RGB Gain controls in the projector's advanced menu to get the
delta RGB error below 1%.
Figure 11. The Adjust White Balance
page provides simplified measurement indicators, and video generator controls,
to make quick work of accurately adjusting white balance.
We
then select the Low IRE pattern and adjust the projector's RGB Offset controls
to again get the delta RGB error below 1%. When both the Low and High IRE
points are adjusted for minimum error, we'll proceed to the Adjust User Controls
page.
Step 8: Adjust
User Controls
With
white balance now properly set, its time to make a final adjustment of the
user controls. Depending on the type of video input we are feeding, the display
may provide the five main controls (brightness, contrast, color, tint, sharpness),
or may provide only brightness and contrast. We simply follow the on-screen
instructions for each of the five main controls to accurately adjust whichever
controls are provided.
Figure 12a. Adjust User Controls —
Brightness/Black Level
Figure 12b. Adjust User Controls
— Contrast/White Level
Figure 12c. Adjust User Controls
— Color Saturation
Figure 12d. Adjust User Controls
— Hue/Tint
Figure 12e. Adjust User Controls
— Sharpness/Edge Enhance
Figure 12a-e. We follow the CP6000 software
instructions, as shown, to properly set the brightness, contrast, color, tint,
and sharpness controls.
Step 9: Post-Calibration
Capture
The
Post-Calibration Capture page is the final documentation page. We'll fill
in whatever final display settings information that we wish to document, either
for ourself or for our client. Then we click the Capture button and let the
program step itself through the measurement capture screens.
Figure 13. The Post-Calibration Capture
step records the final control settings and performs a series of automated
measurements to document the display's post-calibration performance.
Step 10: Calibration
Report
We
can preview the final calibration report on the seven Calibration Report page
tabs. Each tab provides a view of both pre- and post-calibration performance
characteristics, for comparison.We can also see an image of what the actual
printed report pages will look like by going to the main menu and selecting
Report/Print Preview.
Figure 14. The Calibration Report
page provides previews of each of the graphs that will be printed on the
final calibration report. There are seven report pages showing Pre and Post
Calibration for each of the tabs shown here.
Professional
Calibration is Fast and Easy
Calibrating
a projector, such as the Epson 1080p with the OTC1000 ColorPro Color Analyzer,
is as simple as following the step-by-step measurement and adjustment procedures
in the Calibration Control Center. The ColorPro software controls the VideoPro
generator automatically, to always provide the correct test pattern required
for each step. Calibration results are documented in professional looking
report pages.
To
learn how you can perform video calibration just as easily with the OTC1000
ColorPro Color Analyzer and the VideoPro Video Generator, call 800-SENCORE
(736-2673) and ask a sales representative about this easy ten-step video calibration
system.
