Laser Level Warping Tips

Process overview

Physically order and align projectors
Tune & zoom projectors
Set warper settings to reflect physical configuration
Warp Process
- Roughing In
- Correct Overlap Placement
- Fine Tuning
Blend Process
- Roughing In
- Fine Tuning

Physical Preparation

Hang projectors so the projected light covers the physical canvas. Make sure to use the native chip ratio on the projector for maximum throw.
Turn the brightness down 50% and the contrast up 75%
Ensure all zoom levels are set equally and use as little zoom as possible to get coverage.
Uniform throws with equidistant overlaps will simplify the warping process. There is no substitute for accurate physical placement using fixings that ensure the projectors do not move once correctly aligned
Order the screens in nVidia Control Panel (or windows display preferences if no GPU manufacturer control panel is available) so that they reflect the physical order on the immersive canvas.
Use a vertical laser level to mark the leftmost vertical edge of projector n such that all of the laser line is contained in the area in which the adjacent projector(s) overlap.

Warper Preparation

Verify that the number of projectors, canvas start position, canvas resolution, content resolution, projector resolution, number of tiles, pipeline and display settings in the appsettings.xml match the physical characteristics of the room, devices and any supplied testcards (only required for installations with more than one projection surface that are not of equal dimensions)

In the blending menu ensure all settings for all projectors are zeroed except for overall Red, Green and Blue gamma entries. These should all be set to 1.

In the view menu turn on info, test cards, control points, warps, and blends.

Warp Process

Roughing In

Turn on full screen from the view menu in the warper

Use the warper controls you are most comfortable with (Touch OSC, mouse, warp menu in warper) to align the left side control points (points first, then handles) of projector n with the vertical laser level line.

Top Tip : Multiple points can be selected at once if using a 2x2 array of control points (ie, a control point at each corner)

Turn off full screen in the View menu of the warper
Move the vertical laser level to mark the rightmost vertical edge of projector n such that all of the laser line is contained in the area in which the adjacent projector(s) overlap.
Turn on full screen from the view menu in the warper
Use the warper controls you are most comfortable with (Touch OSC, mouse, warp menu in warper) to align the right side control points (major points first, then minor) of projector n with the vertical laser level line.
Use the Align button for projector n from the Warping - Advanced menu in the Warper to distribute the grids evenly.

For flat walls this should be the end of the warping process of a single projector as the top and bottom edges should be uniform.

For cylinders, use the top and bottom control points (major first, then corresponding handles) to create a curved edge to match the curvature of the physical canvas. Do not use left/right movement, up/down is sufficient to create a curve.

For domes, follow the process for cylinders but you will need to use left/right movement on the control point horizontal handles to create straight vertical lines to accomodate the vertical curvature of the dome plane. Top Tip: Move the laser level to the ensure that you have these lines straight.

Top Tip:Save Your Warps

Repeat this process for all projectors

Top Tip: If your projectors are uniformly spaced, you can use the Copy Active projector <n> to other outputs in TouchOSC Save Tab to speed up this process. If you do this and find there is discrepancy in the physical overlap areas repeat the warping process so that the left and right edges of the warp grid match the furthest possible extremities of each overlap.

Correct Overlap Placement

The overlap controls the percentage of the image that will be displayed in adjacent projectors to make a seamless canvas.

Overlaps are set in the blending menu in the warper. The settings that influence overlap are left and right overlap for each projector.

Top Tip:For installations where projector overlaps are uniform it is quicker to use Touch OSC to set them all equally. For best results set them individually.

Use the vertical laser level to set a line inbetween the yellow vertical control points of the overlap of projector n and projector n+/-1. This can be physically measured to ensure accuracy.

In the blending menu use the left overlap of the right side projector and increase the value until the green line of the test card is in line with the laser level. Repeat this step with the right overlap of the left side projector.

Repeat this process for all projectors

Warp Process

Fine Tuning

Once the two green overlap markers are aligned, flat wall overlapping projectors should present uniform grids in the overlap area and no fine tuning should be required.

For cylinders, fine tuning of the grids will be required to accommodate any differences in the control point handle positions of adjacent projectors

Top Tip: If you have a 360° horizontal laser, use it as a reference to level top, middle and bottom horizontal rows on the test grid of each projector to ensure uniform horizontal lines throughout the canvas. If a flat line cannot be achieved across the projected arc consider adding an additional control point column. Note that warps have to reset.

For domes, an additional control point row may need to be added to create uniform vertical arcs.

For most physical canvas shapes, small or medium movements around the corner control points and their horizontal handles should be enough to bring a parity to the grid sizes in the relevant corners. Equally applying changes to the top and bottom of a projector and corresponding changes to the adjacent projector controls equally distributes distortion

Blend Process

Roughing In

To set the Blends correctly use the blending menu in the warper. The settings used in this process are left/right width and left/right global gamma (brightness). The left and right width control how much of the projected image is affected by the gamma (brightness setting). The gamma setting controls how much light is being projected (0=0%, 2=50%,4=100%).

Ensure blending is set to ‘on’ in the View menu

With the left/right gamma set to 0, gradually increase the left width of the right side projector until the black gap that is being generated lines up with the right hand side yellow control point line of the projector to your left.
Repeat this process with the right width of the adjacent left side projector until you see a black rectangle filling the overlap area.
Where 2 projectors overlap, logically it is twice as bright. If you set the adjacent projectors left/right gamma to 2 then you should get 50% brightness from both. This is a good base-line from which to fine tune to get the best results for your content. Experience suggests a value between1.6 and 1.8 gives a good blend on most projectors.

Repeat this process for all projectors

Fine Tuning

View your content and use the global gamma control on Touch OSC to refine your baseline. If manual fine tuning is required to mask discrepancies in the projector colour or brightness revert to the blending menu and use the overall red/blue/green gamma settings for each projector as a whole or left/right red, green or blue gamma settings to fine tune the colour gamma in the blend area.

This concludes the process, to ensure that your config is enabled by default do the following

Save your Warps
Press Escape on the Warper, or File Save, never use the X button on the top right corner of the warper window
Reload the warper
Check that the warper has loaded your warps, blends and overlap as the default configuration

Top Tip: Copy the %programdata%\igloo vision\igloo warper\warps folder and %programdata%\igloo vision\igloo warper\appsettings.xml to another location as backup.