> For the complete documentation index, see [llms.txt](https://stage-precision.gitbook.io/grid/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://stage-precision.gitbook.io/grid/camera-calibration/before-you-start/calibration-references/calibration-screens/multi-screen-setup.md). # Multi Screen Setup Use a **Multi Screen Setup** when your Calibration Screen is one connected physical LED surface that is made from multiple panels, columns, or tiles. A Multi Screen is not intended for separate screen surfaces. It represents one continuous Calibration Screen surface where the individual parts are physically connected and can be optimized as one surface. Typical examples are: * one connected LED wall made from multiple columns * a continuous tiled LED surface with an irregular shape * a large flat LED wall that should be treated as a connected panel structure * an LED wall that is expected to be slightly uneven, curved, or wavy * a continuous LED stage section built from repeated modules Grid Studio analyzes and optimizes the connections between the panels or columns inside the Multi Screen. This allows the Calibration Screen to better represent real-world LED surfaces that are not perfectly flat or perfectly aligned. ## When to Use a Multi Screen Setup Use a Multi Screen Setup when the reference surface is one continuous physical LED surface made from connected panels, tiles, or columns. This is common for LED walls, because the wall is often built from repeated LED tiles or columns. Even if the wall looks like one large flat rectangle, a Multi Screen can be useful when the surface is slightly uneven, wavy, curved, or when the panel connections should be optimized during calibration. Use separate Multi Screens when the physical surfaces are not connected. For example, if your setup has two separate LED wall sections, create two separate Multi Screen Calibration Screens instead of combining them into one Multi Screen. Use a **Single Screen Setup** instead if the reference surface is one simple flat rectangle and you do not need to model or optimize individual panel or column connections. {% hint style="warning" %} A Multi Screen should represent one connected physical LED surface. If your setup contains separate wall sections, separated LED surfaces, or independent screen parts, create separate Calibration Screens instead. Do not combine disconnected LED walls into one Multi Screen. {% endhint %} *** ## Step 1: Create a Multi Screen Calibration Screen Create a new **Multi Screen** object in Grid Studio. You can find it by searching for **Multi Screen** or by selecting it from the **Calibration** section when adding a new object.
Give the Multi Screen a clear name that helps you identify the physical surface later, for example: * `Main LED Wall` * `Stage Back Wall` * `LED Columns` * `Floor LED Section` *** ## Step 2: Gather Screen Information Before using the Surface Generator, gather the required information about your LED setup. You need to know: * the pixel size of one LED tile, panel, or column * the physical size of one LED tile, panel, or column * the number of columns or panels * the total output resolution * the total physical size of the connected LED surface For example: ``` Tile size: 176 x 176 px Column: 176 px wide x 1584 px high Column structure: 9 tiles stacked vertically ``` And physically: ``` Tile size: 0.5 m x 0.5 m Column size: 0.5 m wide x 4.5 m high Column structure: 9 tiles stacked vertically ``` {% hint style="info" %} You can enter dimensions in feet if needed. End the value with `ft` and Grid Studio will convert it to meters. {% endhint %} *** ## Step 3: Use the Surface Generator Right-click the Multi Screen object and open the **Surface Generator**. Enter the collected information about your LED columns, tile sizes, physical sizes, and column count.
The Surface Generator creates the panel, tile, or column structure of the Multi Screen. This structure is later used by the calibration system to analyze and optimize the relationships between the connected parts of the surface. This is especially useful for LED walls where the individual panels are not perfectly aligned or where the full surface is slightly wavy or irregular. After entering the required information, close the dialog and check the generated screen structure in the viewport. *** ## Step 4: Set the Screen Resolution After using the Surface Generator, open the **Screen** tab in the Inspector. Enter the full texture resolution for the Multi Screen.
The full texture resolution should match the resolution of the Calibration Image that will be displayed on the LED processor, media server, or output device. Make sure that the configured resolution matches the actual output setup. If the resolution is incorrect, the Calibration Pattern may not match the physical LED surface and the calibration result may become inaccurate. {% hint style="info" %} If you change the screen resolution, regenerate the texture from the **Screen** tab before exporting the Calibration Image. {% endhint %} *** ## Step 5: Set Up the Calibration Pattern After setting the physical and pixel dimensions, configure the Calibration Pattern. Open the **SP Pattern** settings on the Calibration Screen. These settings control how the Calibration Pattern is generated for the Multi Screen.
For Multi Screen setups, **Shuffle** is usually recommended because large LED surfaces often require many markers. ### Tag Generator The **Tag Generator** controls how marker IDs and marker layouts are assigned in the Calibration Pattern. The available modes are: * **Default** * **Shuffle** **Default** generates marker IDs sequentially. This can be useful for simple setups, small printed boards, or cases where you want direct control over the marker ID range. When using **Default**, make sure that the marker ID ranges do not overlap between Calibration Screens. Default mode is limited to `2114` individual marker IDs. **Shuffle** generates a pattern that uses the surrounding marker neighborhood as part of the identification. This allows Grid Studio to use significantly more markers and avoids the same practical marker count limitation as Default mode. Shuffle is usually preferred for larger Calibration Screens, Multi Screen setups, or setups where many markers are required. Default and Shuffle can also be mixed in the same project. For example, you can use Default for small printed boards and Shuffle for larger Calibration Screens or LED walls. {% hint style="info" %} Use **Default** when you need small, simple, or manually controlled marker ranges. Use **Shuffle** when you need many markers or want to avoid running into the Default marker ID limit. {% endhint %} *** ### Start Marker ID The **Start Marker ID** defines the first marker ID used by the generated Calibration Pattern. When the **Tag Generator** is set to **Default**, marker IDs are generated sequentially. In this mode, marker IDs must not overlap between different Calibration Screens used in the same calibration workflow. Directly below the **Start Marker ID** parameter, Grid Studio shows how many markers are used by the current Calibration Screen and which marker ID range is occupied. For example: ``` Markers: 32, IDs: 0–31 ``` This means that the current Calibration Screen uses 32 markers, starting at marker ID `0` and ending at marker ID `31`. If another Calibration Screen also uses the **Default** Tag Generator, it must not use any of these marker IDs. In this example, the next screen should start at marker ID `32` or higher. The **Default** Tag Generator provides `2114` individual marker IDs. After these IDs are used, no additional unique markers are available in Default mode. For larger setups or setups that require more markers, use the **Shuffle** Tag Generator. {% hint style="warning" %} When using the **Default** Tag Generator, marker ID ranges must not overlap between Calibration Screens used in the same calibration. Overlapping marker IDs can make it impossible for the calibration tool to reliably identify which Calibration Screen a detected marker belongs to. {% endhint %} ### Marker Size The **Marker Size** defines the target physical size of the markers in the Calibration Pattern. This value should be understood as an approximate target size, not always as the exact final marker size. Grid Studio avoids interpolating the marker pattern when generating the Calibration Image. A marker is based on a fixed pixel structure, for example `9 x 9 px`. To keep the pattern sharp and reliably detectable, Grid Studio only scales this structure by clean integer steps, such as: * `9 x 9 px` * `18 x 18 px` * `27 x 27 px` * `36 x 36 px` * `45 x 45 px` This means the final marker size may be slightly different from the value entered in the Marker Size field. Smaller markers can provide more calibration data, but only if the camera can resolve them clearly. If the markers are too small, blurry, or only partially visible, detection quality will suffer. {% hint style="info" %} The Marker Size is a target value. Grid Studio may slightly adjust the final marker size to keep the Calibration Pattern pixel-perfect and avoid interpolation. {% endhint %} *** ## Step 6: Save Pattern Configurations Calibration Screens can store multiple pattern configurations. This is useful when the same Multi Screen needs to be used with different marker sizes or pattern settings during a calibration workflow. For example, when using a zoom lens, you may need larger markers while the camera is zoomed out and smaller markers when the camera is zoomed in. Large markers are easier to detect from a wider view, while smaller markers allow more detailed calibration data when the camera sees a smaller part of the screen. Grid Studio provides a **Configurations** tab in the Inspector for this purpose. In the **Configurations** tab, you can: * save the current Calibration Screen settings as a configuration * load a previously saved configuration * prepare multiple marker sizes or pattern setups for the same Calibration Screen The calibration system automatically detects which configuration from this list is currently being used. {% hint style="info" %} Use configurations when you need to switch between different Calibration Pattern setups, for example when calibrating a zoom lens with different zoom ranges. {% endhint %} *** ## Step 7: Set Up a Master Screen For Multi Screen setups, one screen section, panel, or column can be used as the **Master Screen**. The Master Screen defines the reference position of the Multi Screen relative to your chosen zero point in the virtual scene. Grid Studio uses this information to transform the remaining columns, panels, screens, and cameras while keeping the master section fixed. We recommend choosing a clearly identifiable column or section as the Master Screen and naming it accordingly.
For example, you can set the center column as the Master Screen and place it so that the project origin is at the floor and centered on the X axis. If you want the zero point to be 5 meters in front of the screen, you can offset the Master Screen by 5 meters on the Z axis. {% hint style="info" %} Choose a Master Screen that is easy to identify later in the calibration process. This makes it easier to understand how the screen setup is positioned in the virtual scene. {% endhint %} *** ## Step 8: Generate the Texture After changing screen dimensions, Surface Generator settings, pattern settings, or configurations, generate the texture from the **Screen** tab. This updates the internal texture used for the Calibration Image. {% hint style="info" %} Regenerate the texture whenever you change the resolution, marker size, tag generator, pattern settings, or loaded configuration. {% endhint %} *** ## Step 9: Export the Calibration Image Right-click the Multi Screen Calibration Screen and select **Save Marker Image**. This exports the generated Calibration Image as a `.png` file.
The exported Calibration Image must be displayed on the matching LED processor, media server, or output device. {% hint style="info" %} The UI action is called **Save Marker Image**, but the exported file is referred to as the **Calibration Image** in this documentation. {% endhint %} *** ## Step 10: Display the Calibration Image Display the exported Calibration Image on the physical LED surface. Make sure that: * the image is displayed at the correct resolution * the image is not scaled * the image is not cropped * the aspect ratio is correct * no overscan or display processing is applied * the complete Calibration Pattern is visible * the image is mapped correctly to the LED surface If you use an LED processor or media server, you may need to slice or map the Calibration Image to match the tile, panel, column, or output layout. *** ## Before Starting the Calibration Before using the Multi Screen Setup in a calibration workflow, check the following: * The Multi Screen object exists in Grid Studio. * The Multi Screen represents one connected physical LED surface. * Separate LED wall sections are created as separate Calibration Screens. * The Surface Generator was configured with the correct tile, panel, column, and physical size information. * The panel, tile, or column structure matches the real LED layout. * The connections between panels or columns should be optimized as one continuous surface. * The full texture resolution matches the real output setup. * The Calibration Pattern settings are correct. * Required configurations have been saved if multiple marker sizes or pattern setups are needed. * The correct configuration is loaded before generating or exporting the Calibration Image. * The texture was regenerated after changing dimensions, pattern settings, or configurations. * The Calibration Image was exported from the correct Calibration Screen. * The Calibration Image is displayed pixel-correctly. * The complete Calibration Pattern is visible in the live camera image. * The LED surface does not move during calibration. * The selected calibration tool is configured to either use or update the Calibration Screen placement as needed. Once the Multi Screen Setup is ready, it can be used by calibration, alignment, or repositioning tools that require Calibration Screens.