Getting started with Smartshow LMS

Smartshow LMS drives LED matrices, strips and pixel walls from a computer. It sends Art-Net, sACN, DMX over USB, or a video feed over HDMI, and it is free — including for commercial use.

This guide takes you from a fresh download to lights actually moving. It assumes you have LEDs wired to some kind of controller and that the controller is powered and on your network.

1. Install and open LMS

Download the installer for your platform and run it. On Windows you may see a SmartScreen prompt the first time — the installer is code-signed as Hi-Lite Entertainment Limited, so if you see that name you have the genuine article.

There is no account, no licence key and no trial period. It opens and it works.

2. Tell LMS the shape of your wall

The single most important setting. In the matrix settings, enter the size of your LED surface in pixels — not in metres, not in panels.

A 32 by 16 pixel wall is 32 × 16. Four 16×16 panels in a row is 64 × 16. A single strip of 150 pixels is 150 × 1 — a strip is simply a matrix one pixel tall, and everything else works the same way.

Get this right before you go further. Every effect is drawn onto this canvas, so if the size is wrong nothing downstream will look correct no matter what else you fix.

3. Choose how the pixels get out

You have four routes out of LMS, and which one you use depends entirely on your hardware.

For Art-Net, set the target IP address explicitly to your node's actual address. Leaving it on a broadcast address is the single most common reason nothing arrives — the packets go out onto the wrong subnet and vanish without any error.

4. Add an effect and press play

Pick something big and obvious for the first test — Plasma, Rainbow or Solid. Resist the temptation to start with something subtle. When you are proving a signal path you want a result where "working" and "not working" are impossible to confuse.

Press play. The preview should move, and so should your wall.

5. If nothing lights up

Work down this list in order. It is arranged most-likely-first, and between them these five account for the overwhelming majority of first-time problems.

Is the patch empty? As soon as the patch contains any rows at all, the patch decides what every output sends — there is no partial mode. A single leftover row from an experiment will silently stop an unpatched protocol sending anything. Either clear the patch completely, or give your protocol its own rows.

Is the target IP right? As above: an Art-Net broadcast address on the wrong subnet fails silently.

Is the universe number right, and does it match what the controller expects? Off-by-one here is extremely common, because some manufacturers count universes from 0 and others from 1.

Is something else holding the port? Only one application can bind UDP 6454 for Art-Net. FreeStyler and similar tools grab it on launch and keep it, and LMS will then send into a void. Close the other software and try again.

Are the colours rotating along the run? If the first pixel is right but colours drift as you go along, your universe channel count is wrong. A DMX universe is 512 channels and an RGB pixel is 3, which does not divide evenly — declare the real count, 170 × 3 = 510, not 512.

6. Read the fixture's DMX chart before blaming the software

If a fixture responds but behaves strangely — flashing when it should fade, ignoring colour changes, jumping to full — check what its channels actually do.

Plenty of fixtures put a strobe, a mode select or a master dimmer on a channel you are feeding pixel data into. On some units any value above roughly 200 on the first channel switches it into strobe mode, so a bright frame makes it flash and it looks for all the world like a software fault.

This is worth checking early. It costs two minutes and saves an evening.

7. Where to go next

• Effects — there are over seventy, grouped by category. The Strip / 1D group is designed for single-line LED strips but works on any matrix.
• Audio reactive — most effects can respond to live audio, and Spectrum Bars has proper RTA modes.
• Manual — the full reference is at [smartshowlms.leejamesapps.co.uk/help](https://smartshowlms.leejamesapps.co.uk/help/), and it opens in your browser so you can use Translate for any language.
• Forum — if something is genuinely broken, post it. LMS is actively developed and bug reports get read.

A note on what LMS is not

LMS is a pixel and effects engine. It is not a lighting desk: it does not do cue stacks, timecode or conventional fixture control. If you need those, run LMS alongside a desk and let each do the part it is good at — plenty of people drive the wall from LMS and everything else from their usual console.