Dome Projection Setup

This guide covers setting up Exaplay 3 for dome projection — full-dome digital planetariums, immersive art domes, inflatable event domes, and simulation domes.

Dome Projection Basics

A dome screen is a hemispherical surface. A standard flat-screen projector cannot illuminate it correctly without a special optical element and geometric correction:

Approach	How it works	Best for
Single fisheye projector	One projector with a fisheye lens illuminates the entire dome from below the centre	Small domes (≤ 8 m), inflatable domes, mobile setups
Multi-projector ring	4–6 standard projectors arranged around the dome, edge-blended at the joins	Large permanent domes (> 8 m), planetariums, simulation domes

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Part 1 — Single Fisheye Projector Setup

Hardware requirements

• One projector with a 180° fisheye projection lens
• Projector positioned at the dome's tilt point (below centre, angled up)
• Ensure the projector's lens covers the full dome with a single image

Step 1.1 — Set up the Output

1. Open Config → Outputs → + Add Output.
2. Set resolution to the projector's native resolution (typically 2048 × 2048 square for dome, or 4096 × 4096 for higher quality).
3. Enable the output on the projector's display.

Tip: Most dome content is created in a square aspect ratio (1:1) — the fisheye lens handles the mapping to the dome surface. Use a 2K or 4K square framebuffer for best quality.

Step 1.2 — Load Fisheye Calibration (if using VIOSO)

If your fisheye projector has a VIOSO calibration file:

1. Open Config → Outputs → Load Warp File.
2. Select the .vwf file from VIOSO Calibrator.
3. Toggle Warp Enable on.

If you don't have a VIOSO calibration file, use the Manual Warp Editor to do a rough alignment (see below).

Step 1.3 — Manual Warp Adjustment

1. Open Config → Outputs → Edit Warp.
2. Use a test pattern (cross-hatch or grid) as the output content.
3. Move the control points on the grid to align the projected image with the dome seam.
4. Use arrow keys for fine adjustment (0.01 steps) and Shift + arrows for coarse (0.1 steps).
5. Switch interpolation to Bicubic for smoother warping on a curved surface.

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Part 2 — Multi-Projector Ring Setup

For large domes, a ring of projectors each covers a ~90° sector of the dome, with a 15–25% overlap at the joins.

Hardware Layout Example (4-projector ring)

Step 2.1 — Add One Output per Projector

1. Open Config → Outputs.
2. Add one output per projector (e.g. Output 1: North, Output 2: East, etc.).
3. Set each output's resolution to the projector's native resolution (1920×1080 or 1920×1200 for standard dome projectors).
4. Assign each output to a separate display port on the Exaplay PC's GPU.

Step 2.2 — Calibrate with VIOSO AutoAlign

For large permanent domes, VIOSO AutoAlign is the professional choice:

1. Connect a calibration camera (e.g. Canon DSLR with a fisheye lens) to the Exaplay machine.
2. Go to the Auto Calibration view (http://<ip>:8123/autocalibration).
3. Follow the on-screen wizard — VIOSO fires structured-light patterns at each projector in sequence.
4. The wizard produces a .vwf file for each projector automatically.
5. Load each .vwf into its respective output in Config → Outputs.

For full details see Projection Mapping & Warp/Blend.

Step 2.3 — Manual Edge Blend Adjustment

After loading calibration files, fine-tune the edge blend:

1. Open Config → Outputs → Edge Blend for the first output.
2. Increase Blend Width on the overlapping edge until the join becomes invisible.
3. Adjust Gamma Curve — dome surfaces scatter light differently; a lower gamma (e.g. 1.8) often gives a better blend on fabric domes.
4. Repeat for all overlapping edges.

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Part 3 — Dome Content

Fulldome Format

Dome content is typically delivered in fulldome format — a 360° circular image inside a square frame, representing a top-down or angular view of the dome hemisphere:

Standard fulldome resolutions:

• 2K fulldome: 2048 × 2048 px (small domes, real-time)
• 4K fulldome: 4096 × 4096 px (medium/large domes)
• 8K fulldome: 8192 × 8192 px (permanent planetariums — requires high-end GPU)

Codec recommendation: Use HAP Q for 4K fulldome content — it provides GPU-accelerated decode with no CPU bottleneck. At 8K, consider splitting the content across two clips on separate tracks and outputs.

For Multi-Projector Setups

Each projector receives a pre-rendered sector slice of the fulldome image. Ask your content creator to export the dome content as individual slices matching each projector's coverage angle and resolution, or use VIOSO's pixel-mapping to project the full equidistant image across all outputs automatically.

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Part 4 — Audio for Dome

Immersive domes typically use ambisonic or multichannel spatial audio to match the 360° visual experience.

1. Open Config → Audio Settings.
2. Select an ASIO interface with enough output channels (8+ for immersive audio).
3. Route each audio channel to the correct speaker position in the dome.
4. In the Timeline, use separate audio tracks per speaker group (front, left, right, rear, top).

See Audio for ASIO routing details.

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Part 5 — Show Operation

Cue-Based Shows (Planetarium Programs)

1. Build the programme as a composition with the full show timeline.
2. Create cues at each programme segment for the presenter to advance the show manually.
3. Use the Operator Control View (/control) on a presenter tablet.

Continuous Loop (Art Installation)

1. Set the composition to Loop: ∞ Infinite.
2. Configure the Scheduler to start the loop when the venue opens and fade to black when it closes.
3. Enable Auto-Heal for unattended operation between shows.

Live Presenter Mode

For a live presenter performing under the dome (narrator, musician):

1. Set up NDI or a capture card as a live input if you want to feed camera footage of the presenter into the dome content.
2. Create a dedicated PRESENTER track in the composition — drag the NDI source onto it.
3. In the Playlist, add a cue that enables the presenter track and another that hides it.

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Part 6 — Performance Considerations

Factor	Recommendation
GPU	NVIDIA RTX 3080 / 4080 or better for 4K fulldome; 4090 for 8K
CPU	8+ cores; HAP decoding is GPU-bound but CPU handles decompression metadata
RAM	32 GB minimum; 64 GB for multi-projector 8K setups
Storage	NVMe SSD for content drives; > 2 GB/s read speed for 4K HAP Q
Network	Gigabit Ethernet if using NDI live inputs inside the dome
Cooling	Good airflow is essential — GPU and CPU run at near 100% during dome playback

Use the Diagnostics Panel in the Control View to monitor GPU, CPU, RAM, and VRAM usage during the show.

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Summary Checklist

Single-projector fisheye:

• [ ] Square output resolution configured (2K or 4K)
• [ ] Fisheye warp calibration loaded or manual warp adjusted
• [ ] Fulldome content format confirmed (circular image in square frame)

Multi-projector ring:

• [ ] One output per projector, each assigned to correct display
• [ ] VIOSO AutoAlign calibration run and .vwf files loaded
• [ ] Edge blend width and gamma tuned per overlapping edge
• [ ] Content delivered as sector slices (or VIOSO pixel-mapped)

Both setups:

• [ ] HAP or HAP Q codec used for all dome content
• [ ] ASIO multichannel audio routing configured
• [ ] Playlist built for show navigation
• [ ] Diagnostics Panel checked during full-load test
• [ ] Auto-Heal enabled (for unattended dome loops)