Choosing an alignment approach

Moonshine gives you three ways to put a projected image exactly where you want it. Choosing the right one first saves you from undoing work later.

The mental model

Every alignment problem is one of two kinds, and you fix each one in a different place.

The projector is in the wrong place, so its image is the wrong shape. The projector is off-axis or tilted, or it's throwing onto a slightly curved wall. The content is fine, but the light lands distorted. Fix this by reshaping that projector's output on the Warp tab.

The image is the right shape, but the model isn't. Your surface model doesn't match the real object: the wall bulges, the truss sags, or the set was built 40 mm off the drawing. Fix this by moving the surface itself in Warp mode on the Scene tab. Every projector lighting that surface picks up the change.

Which one to use

Approach	Where you work	What it moves	Applies to
4-corner keystone	Warp tab → 4-Corner	The four corners of one projector's output	That projector only
Bezier mesh	Warp tab → Bezier Mesh	A grid of control points across one projector's output, with curve handles	That projector only
3D surface warping	Scene tab → Warp mode	Points on the surface model itself, in 3D	Every projector lighting that surface

Use each one when:

• 4-corner keystone: the projector is off-axis and the image lands as a trapezoid on a flat surface. Drag four handles and you're done. Try this first on any flat wall or screen.
• Bezier mesh: the corners are right but the middle isn't. Use it for a curved wall, a cyclorama, a local fix inside an overlap, or lens distortion the corners can't reach. You choose how many rows and columns to use, and each point has curve handles that keep a bend smooth.
• 3D surface warping: you're mapping an object rather than a screen, and the model doesn't match what was built. Pulling the model onto the real object corrects every projector at once and keeps them in agreement with each other.

On a flat screen, stop at 4-corner

A bezier grid can do everything four corners can, but each extra control point is one more thing to knock out of alignment. Add rows and columns only where the surface needs them.

How the three relate

4-Corner and Bezier Mesh edit the same warp. Each projector has one output warp, and the two modes are two ways to edit it. The first time you switch a projector from 4-Corner to Bezier Mesh, Moonshine builds a 4 × 4 grid from the corners you already set, so nothing is lost. After that the two stay in step. Dragging a corner in 4-Corner carries the whole grid with it, interior points included, and dragging a grid corner in Bezier Mesh moves the four corners.

3D surface warping is separate, and it's shared. It changes the surface rather than one projector's output, so it stays in place when you move a projector, and every projector aimed at that surface shows it. It's also the only one of the three that several operators can edit at the same time. See Editing a surface together.

A working order

1. Place your surfaces and projectors in the Scene. Get their positions roughly right before you correct anything. If you move a projector later, you'll have to redo its alignment.
2. Square up each projector with 4-corner keystone on the Warp tab.
3. If the surface is curved or the middle still drifts, switch that projector to a bezier mesh. Add rows and columns only where you need them.
4. For object mapping, switch to the Scene tab and sculpt the surface in 3D until the model sits on the real object.
5. Bake the warp so the show machine restores the aligned shape every time the project opens.

Before you start

• Keystone and bezier corrections apply to one projector at a time, so select the projector you want to correct first. See Projectors.
• Opening the Warp tab takes the warp lock for the surface you're working on. The lock covers the corners and grid of every projector on that surface, and you release it when you leave the tab. See Locks.
• Ctrl+Z undoes moves of corners, points and handles, both on the Warp tab and in 3D surface warping. On the Warp tab, a quick run of arrow-key nudges is one undo step; in 3D surface warping, each nudge is its own step. Changes to the grid itself can't be undone: adding or deleting rows, columns and lines, collapsing or expanding handles, switching Linked/Independent, and the resets. Ctrl+Shift+Z redoes reliably only in 3D surface warping and in the 4-Corner editor.