The Liquid Retina XDR display and Ultra Retina XDR display on your iPad Pro can display reference color for popular color standards, as well as SDR and HDR video formats.
What is Reference Mode?
Reference Mode is a display mode for professional content creation workflows, like color grading, editing, and content review, where accurate colors and consistent image quality are critical.
To use Reference Mode (which can affect battery life), you need one of these devices: iPad Pro 13-inch (M4), iPad Pro 11-inch (M4), and iPad Pro 12.9-inch (5th or 6th generation) running iPadOS 16 or later.
When Reference Mode is on, your iPad Pro displays reference color for these common color standards and video formats, up to 1,000 nits peak brightness for HDR and 100 nits peak brightness for SDR: BT.709, BT.601 SMPTE-C, BT.601 EBU, sRGB, HDR10 BT.2100 PQ, BT.2100 HLG Dolby Vision Profile 8.4, and Dolby Vision Profile 5.
Reference Mode enables your iPad Pro to match the color requirements of your workflow. It targets a D65 white point and disables all dynamic display adjustments for ambient surround, like True Tone, Auto-Brightness, and Night Shift. You can also adjust the white point and luminance manually. Unsupported formats are color managed as they would be in the default display mode.
To turn Reference Mode on or off:
° Open the Settings app, then tap Display & Brightness.
° Tap Advanced.
° Turn Reference Mode on or off.
° Use an external instrument to measure a test pattern. Note the values you measure.
° Go back to the Settings app, then tap Display & Brightness. Tap Advanced, then tap Fine-Tune Calibration.
° Tap the space next to each setting to enter a value. Enter the values you measured in the Measured fields. Enter your target values for white point and luminance in the Target fields.
° When you’re finished, tap Done. Your iPad Pro display will adjust to match your white point and luminance target.
Here are the descriptions of what to enter in the Measured and Target fields:
° Measured White Point (x): The x chromaticity coordinate (CIE 1931 xyY) when measuring a white or gray test pattern.
° Measured White Point (y): The y chromaticity coordinate (CIE 1931 xyY) when measuring a white or gray test pattern.
° Measured Luminance (cd/m2): The Y luminance value (CIE 1931 xyY) when measuring a white or gray test pattern.
° Target White Point (x): The x chromaticity coordinate (CIE 1931 xyY) of your target white point.
° Target White Point (y): The y chromaticity coordinate (CIE 1931 xyY) of your target white point.
° Target Luminance (cd/m2): The Y luminance value (CIE 1931 xyY) of your target luminance.
To remove any previously applied Fine-Tune Calibration, tap Restore Defaults.
You can use QuickTime movie test patterns from Apple to evaluate the calibration of your iPad Pro. These appropriately color-tagged references allow you to use your in-house measurement instrument to fine-tune the white point and luminance calibration of your display. Go to the Go to the AVFoundation Developer page and:
° In the Related Resources section, click Color Test Patterns to download the test files.
° In the Files app, decompress the QuickTime-Test-Pattern.zip archive. Each set of test patterns includes a Reference Values.txt file that lists the expected chromaticity and luminance for each test pattern. Only the following QuickTime test pattern sets are recommended for the iPad Pro: HDR10_ST2084, SDR_BT601_NTSC_SMPTE_C, SDR_BT601_PAL_EBU, and SDR_BT709_HDTV.
When measuring a test pattern and fine-tuning your display:
° Align your measurement instrument to the center of the display.
° Verify that your instrument is perpendicular to the surface of the display.
° Make sure that the room is dim or dark to prevent stray light or glare from affecting the measurements.
° Make sure that the display has warmed up for at least 30 minutes and is thermally stable.
° Measure and fine-tune in an environment with ambient temperatures of 77° F/25° C or cooler.
° You don’t need to remove an existing Fine-Tune Calibration before measuring and applying a new one.
Range limits for Fine-Tune Calibration
The data fields for the three measured values have static valid input ranges so that you can measure a wide range of test patterns.
The achievable ranges for the target x and y data fields are calculated based on the measured x and y values and any existing Fine-Tune Calibration.
The achievable range for target luminance is calculated based on the measured x, y, and luminance values, the target x and y values, and any existing Fine-Tune Calibration.
Achievable ranges for the target data fields are shown next to the fields. If you enter a value that is outside of the achievable range, the range is highlighted in red.
If your desired target value is outside the displayed range, it might be a result of one or more of the following:
° Measurement values from your instrument might not be correct. Verify that your instrument is perpendicular to the display and aligned to the center of the test pattern.
° The values you entered into the measured fields might be incorrect. Verify that the measured values entered match the measurement data you collected from your instrument.
° The values you entered into the target fields might be incorrect. Verify that you are using your intended test pattern and that the target values entered into the target fields match the expected chromaticity and luminance of the measured test pattern.
° Desired luminance target might not be achievable. iPad displays are engineered to be the best in the industry. All displays might be susceptible to reduced brightness levels as the display ages over time, which might make your luminance target no longer achievable. In this case, the display’s white point accuracy can still be maintained.
