The below article contains excerpts from The Display Calibration Guide.
When you first start HCFR, all you will be presented with is an empty screen with two buttons available in the tool bar:
- Create a new project
- Open an existing project
Additionally, you will be able to go to the menu system and configure preferences. You can do it in either order. However, for simplicity, let’s create a new project first.
Let’s click on the empty page icon to start creating our first project. The software will take you through some critical project configuration next. Let’s have a look at these steps.
STEP 1. Generator Selection
This is where you select whether you want HCFR’s internal pattern generator (automatic option) or manual patterns. Automatic is also the option to select for an external pattern generator such as MadTPG, Chromecast or PGenerator. Alternatively, you can use manual pattern generation through disc.
STEP 2: Meter Selection
On this screen you can select the meter you will be using – whether a colorimeter or a spectrometer. Alternatively, you can also choose the simulated sensor if you simply want to practice with the software.
You will also be able to select either an existing correction matrix, create a new one or not use one if your colorimeter supports this option.
As explained earlier, correction files can be created by profiling a colorimeter with a spectrometer for a particular display or display type.
However, basic correction files are provided within HCFR on the next screen for a lot of display types if you are using either the ColorChecker / i1Display Pro or the Spyder. These will work well in most cases.
If you don’t have a correction file, tick “Do not use a meter correction file” and click Finish.
If you are using the simulated sensor, you will need to select “Create new correction file”. You will set this up on the next dialogue box.
STEP 3. Set up Sensor / Meter (Parameters)
This dialog will depend on whether you have selected a simulated sensor, a sensor without included correction files or one of the sensors that HCFR has built-in corrections for. Let’s cover what happens when you have a sensor without any connections.
STEP 3A. Simulated Sensor / Sensor without in-built Corrections
If you selected the simulated sensor, you will need to set up the simulation: its lack of baseline accuracy (offsets) and the randomisation of errors.
On the next tab, you are able to set up a correction matrix just like for any other sensor without a matrix.
STEP 3B. Sensor with Built-In Corrections
For a sensor with built-in corrections, the dialogs are different. However, they will also be different dependent on whether you have ArgylCMS installed or the make and model of your sensor. It is a good idea to read the manual that comes with your sensor as the options will be explained there in more detail. If you are using ArgylCMS, you can refer to the documentation on their website.
For the below example, I am using i1Display Pro with ArgylCMS. Let’s go through the options:
Select the sensor on the Sensor Selection Dialogue. You will be able to select “Do not use a meter correction file”.
On the next dialogue, you will need to select 3 things:
- Display Type: these are the built-in spectral corrections for the sensor. Try and select the correction that best describes your display.
- Reading Type: this is the mode you are using your sensor in. For example, for the i1Display Pro, the 3 modes are: Ambient, Telephoto and Display. The ambient mode is for looking at environmental readings such as ambient light in the room or paining the sensor at a projector’s lens. For this mode, the diffusor cap needs to be in front of the sensor. Telephoto is for projectors and is used by pointing the sensor at the projector screen without the diffusor in place. The Display mode is for making hard contact with a TV or monitor. It’s important to read the user guide for your particular sensor as the options may vary here.
- Observer Type: leave this at default. These are the colour matching functions based on different research done by different sets of people. The reason for 2 degree and 10 degree counterparts in some of the observer types is due to the eye’s different sensitivity when viewing objects at different angles / degrees. This choice affects how the software reports deviation errors (dE). It is best to leave this at default for now.
The other options on this page are:
- Use Hi-Res Mode: this is available for the i1Pro family of spectros. You can read more about it here: https://www.argyllcms.com/doc/i1proHiRes.html
- Integration time: best to leave this at default. This is thetime the sensor is allowed to adapt to the light before a measurement is taken. This is adaptive with most meters as they take longer to adapt to low light than brighter patterns or patches. If you have issue with the sensor reading low light pattern accurately – and it doesn’t support adaptive mode – you can specify a higher integration time here.
- Calibrate Meter: some meters need to be calibrated by placing them on a dark surface face down and then clicking this button. The software will walk you through any calibration that may need to be completed for your meter.
The Project Screen in Detail
The Project Screen is divided up into 3 main sections: Command, Measurement and Monitoring sections (refer to the diagram on the next page).
The Command Section houses the menu and the command icons. I arranged my first row of command icons to control the project and data, the second row to control the measurement section such as completing greyscale, primary and secondary colour measurements as well as performing an individual measure (camera icon) and continuous measure (start button). We will be using the continuous measure command a lot so good to remember it. The third row controls the graph visibility.
The Measurement Section houses the measurements we will be taking. The first dropdown on the top left of the section controls the type of measurements we can take, whether it is greyscale or colour measurements. It is a good idea to select each in turn and see how the measurement columns change.
You can also access the measurement configuration sections such as the Sensor configuration dialog as well as the Pattern Generator configuration dialogue (whether automatic or manual).
While we are learning, we will be using the default xyY standard for measurement display (configured on the far right under the [Measurement] Display configuration section).
When xyY is selected, the measurement window rows correspond to the following:
- x: the measured x coordinate of the patch on the xycoordinate system for the standard selected. (as seen onCIE graph)
- y: the measured y coordinate of the patch. (as seen on CIEgraph)
- Y: the measured luminance / brightness of the patch.
- DeltaE: the Delta E error for the patch compared to thestandard. Anything below 3 is not perceptible in real-worldcontent. Anything above 3 is visible.
- delta xy: the DeltaE error when NOT taking intoconsideration the Y (luminance) information.
- Y target: the luminance target for the patch you need to becalibrating to. This is very useful when calibrating the gamma or EOTF.
- The measurement columns correspond to the different measurements. You have a few options for measuring them:
- You can click on Go button on the right hand side tomeasure all patches one after the other. We usually do thisfor profiling.
- You can click on an individual column and take a quickmeasurement (camera button in the command section). You can do this to quickly re-measure a patch such as after an adjustment on the display or if it was incorrectly measured.
- You can click on an individual column and click on the Continuous Measure button in the Command Section to continuously measure the patch. This is what we will use when we are adjusting the display and monitoring the effect of the changes.
The monitoring section has two windows: the one on the left called Selected Color shows the metrics of the selected measurement. This window is live so will continuously update doing a continuous measurement. It shows all the metrics that are available through the various Measurement Display types in the measurement section.
The little 4 column diagram in this section shows the RGB levels as a % which is incredibly useful when trying to balance the 3 colours for 100%/100%/100% to achieve a perfect greyscale. In addition, the fourth column shows the dE number which we will aim to minimise as much as possible.
The information window on the right shows the diagram that is selected using the drop-down (e.g. RGB levels on the diagram on the previous page). These diagrams are also available as tabs at the bottom for an easier-to-see full-screen view. Let’s have a look at this next.
The bottom tabs allow you to call up the various diagrams for gamma, luminance, etc. More options are available
- By right-clicking in this section
- By using the last row of icons in the command section
- By using the graphs menu
Explanation of Graphs
The following graphs are available on both the project screen and as separate tabs:
- Measures – this is your project screen
- Luminance – to calibrate luminance in both SDR and HDR (Very handy for HDR however).
- Gamma – to monitor and calibrate gamma in SDR
- RGB Levels – to see the balance of colours across themeasured greyscale levels
- Colour Temperature Graph – to see the colourtemperature and how far away it is from reference (I justuse the RGB levels graph as it tells me the same thing).
- CIE Diagram – to monitor and calibrate the CMS
- Near Black Luminance Graph – this is useful whencalibrating near black as near-black targets are very hardto see on the Luminance or Gamma Graph.
- Near White Luminance Graph – as as above – usefulwhen the targets near white are hard to see on theLuminance Graph.
- Saturation – Luminance Graph – displays the Y(luminance) value for each colour. Useful when calibratingthe luminance of colours in the CMS.
- Saturation – Shifts Graph – displays the same information as the above but as % deviation from standard.
- Combined Graph for Free Measures – as it says on the tin. However, we won’t be working with free measures in this guide.
I have underlined the tabs that we will be using for this guide (SDR Volume 1)! I encourage you to occasionally look at the other tabs as you walk through this guide, but we won’t cover them specifically. These tabs will give us all the information we will need while learning.
The Display Calibration Guide
If you would like to learn more about displays, and display calibration, you can get The Display calibration Guide here.