Projection mapping at home: a beginner’s guide

Published October 8, 2026

Short answer. Projection mapping means bending and cutting a projected picture so it lands only on a real object: a door, a box, a window, a pumpkin. At home you need a projector, a phone with an HDMI adapter, a dark room and one flat surface to start with. Setup takes about five minutes the first time.

A normal projector shows a rectangle. If the wall has a door in it, the rectangle lands on the door, the frame and the wall around it. Mapping fixes that. You pull the corners of the picture until it covers the door and nothing else, so the door looks like it is the screen.

The basic move is corner pinning: four corners, dragged by hand. That is all you need for a first project.

The tools, briefly

Desktop programs like MadMapper or HeavyM do this with layers, timelines and a lot of settings. They are built for stage work, and they take hours to learn. For a door or a window at home you do not need any of that. An app that runs on the phone you already own is enough, and it can send the picture to the projector over HDMI or AirPlay.

What you need

A projector. Any projector with an HDMI input. See the section below on what to look for.
A phone or tablet. An iPhone or iPad, with a USB-C or Lightning to HDMI adapter and an HDMI cable. AirPlay works too, with some lag.
A surface. Start with one that is flat, pale and matte.
Darkness. The room should be as dark as you can make it.
Power. The projector and the phone both need to stay plugged in for a long session.
Something to put the projector on. A shelf, a tripod or a stack of books.

What to look for in a projector

You do not need an expensive one. Three numbers matter:

Brightness in ANSI lumens. For a window, or an object indoors in a dark room, 300 or more. For a one-car garage door, 1,000 or more, and 2,000 or more for a two-car door. For a whole house front, 3,000 or more, and more near a streetlight. Many cheap listings show huge numbers that are not ANSI lumens, so check the spec sheet.
Throw ratio. It is the distance to the surface divided by the width of the picture. A ratio of 1.2 means a 1.2 meter (4 foot) wide picture from 1.44 meters (4.7 feet) away.
Native resolution. 720p is fine for glowing effects. 1080p is nicer for sharp lines. A projector that “supports” 4K but shows 480p is not a 4K projector.

The cheap projector guide goes through each one with examples. For specific models and the right adapter for your phone, see recommended gear.

Pick a first surface

Choose something with four clear corners, so you can see what you are doing.

Good first picks: a white cardboard box, a door, a blank wall, a window with a sheer curtain.
Harder: glossy surfaces, dark brick, anything with a strong texture. They swallow light or scatter it.
Skip for now: bare glass, mirrors and anything that moves.

A box is the best teacher. Light a pale box from the front and you can see at once whether the corners match.

Map it in five steps

Place the projector. Aim it at the surface as straight as you can. Pull focus until the edge of the picture is sharp.
Connect the phone. Plug in the adapter. Bengala shows the projector at the top of the home screen when it finds it. To check the picture, tap the projector status on Home, then Show test pattern. The grid on the wall tells you the connection works.
Add a shape. A polygon with four points is the quickest. Circles suit pumpkins and round lamps.
Drag the corners. Zoom in on the phone and nudge each corner onto the matching corner of the real object. The picture bends to match, so the projector does not have to be perfectly square to the wall.
Fill the shape. Pick an effect, a photo or a color. Turn the room lights off.

Turn off keystone correction on the projector itself. It scales the picture digitally and makes it softer, and the app already does the correcting.

Mistakes everyone makes

Too much light in the room. A projector cannot show black. Any lamp or streetlight makes the picture look washed out.
A weak projector on a big wall. Make the shape smaller instead. A small bright picture beats a big dim one.
Starting with the hardest surface. Do the box first.
Letting the phone sleep or the cable fall out. Keep both plugged in. Bengala keeps the screen awake while a project is open.

Where to go next

Add a second shape for a second object. Try a stencil, which turns a PNG with a transparent background into a shape. If you are doing Halloween, read about projecting on a window or the house projection ideas.