Welcome

This guide is a little different from the ones before it. Instead of using a tutorial format, we’ll go through each of Lumen’s submodules one-by-one to tell you the how they each work in intricate detail.

We’ll list a couple patch ideas for each submodule - these are meant only to be a collection of building blocks to jump-start your creativity. Keep in mind while reading that any of these patch ideas can be combined with any of the other ones to create unique and advanced synthesis techniques.

Recommended Reading The patch ideas presented here won’t be as useful to you aren’t familiar with the Patch Panel. Why not dive into our Patch Panel guide if you haven’t already?

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Camera

The Camera module consists of two parts:

• Input Selection Dropdown: Available on all Panels, you can use this to select a video input source. See our External Signal Processing guide for more information on the types of sources available.
• Camera Out Port: The selected input source’s current frame will be available as a video signal from the Camera submodule’s Out port on the back.

When you have an external video source selected, the white LED above the Camera Out Port will light up.

Pro Tip Be aware that having a video source selected uses up your computer resources, even when you aren’t using it! Therefore it’s best to select “None” from the dropdown when you aren’t doing anything with the signal.

Frames from the selected video source will be resized and cropped to fill the Lumen patch’s screen area, matching resolution and aspect ratio. Therefore, you’ll maintain the highest level of fidelity in your images if the video input source is 640 pixels wide and 480 pixels high.

Patch Ideas

External Feedback

This one is amazingly fun and endlessly flexible. Get an external webcam and select it from the Camera dropdown. Then use its output in your patch, and point the webcam back at a screen or TV that you have showing Lumen’s output full-screen. More info can be found in our External Signal Processing guide.

Lumen as a Video Effect

If you have other video processing apps that can send or receive video using the Syphon protocol, you can use Lumen with them as an “external” video effect:

1. Send your video to be processed from your other app using Syphon.
2. Then pick the app’s Syphon port in the Input Selection Dropdown.
3. Create a patch that processes the signal from the Camera Out.
4. Eventually bring the signal path back to the In port on the Master submodule.
5. Lumen automatically publishes whatever is patched into the Master submodule over Syphon, so you can now use that processed image in your other apps.

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Crossfader

Lumen’s Crossfader takes in two signals, In A and In B. It performs a weighted average between these two signals and sends the resulting signal to its Out port.

The Fade Knob (the one in the center of the submodule) controls the weights of the average:

• To the left, only In A will be shown at the Out port.
• In the middle, In A and In B will be averaged equally.
• To the right, only In B will be shown at the Out port.

The Crossfader can be modulated by patching a signal into the Control In port. You can imagine the Control In signal as twisting the Fade Knob left and right on your behalf. When a signal is patched to Control In, the Fade Knob now controls the amount and direction of modulation.

It’s only accessible via the Patch Panel.

Patch Ideas

2-Channel Mixer

I often use the Crossfader as a “spare” mixer:

• Patch: One signal into In A
• Patch: A second signal into In B
• Fade Knob: Controls the mix between the two

Fader / VCA

Just like using it as a Crossfader, but don’t patch anything into In B:

• Patch: Input signal into In A
• Patch: Signal to control the amount of fade into Control In
• Fade Knob: Controls the amount of fade modulation

Trails / Framebuffer / Freeze Frame

You can turn the Crossfader into an effect similar to Trails:

• Patch: Input signal into In A
• Patch: From the Out port back into In B
• Fade Knob: Almost all the way to the right but not quite. Play with the level to adjust the effect amount!

This can be made voltage controllable by patching into the Control In port!

Also, you might notice that if the Fade Knob is all the way to the right, the frame freezes! So if you patch into the Control In port with a signal that goes 100% bright (like one from an Oscillator in Key Mode), you now have a voltage-controllable freeze-frame… NOT BAD

For bonus points, try putting Transform effect between Out and In B with a little bit of rotation.

Rectifier

This use of the Crossfader takes an input signal and effectively mirrors the waveform around its middle, doubling the perceived frequency (number of lines) but reducing the amplitude of the signal (contrast between light and dark):

• Patch: Input signal into In A
• Patch: The same signal into Control In
• Fade Knob: All the way to the right

Waveshaper

You can also use the Crossfader to slightly increase the contrast of images (by darkening the already-dark parts).

• Patch: Input signal into In A
• Patch: The same signal into Control In
• Fade Knob: All the way to the left

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Dual LFO

The Dual LFO houses two of Lumen’s three LFOs, or Low-Frequency Oscillators. We will refer to these here as “LFO A” and “LFO B”." LFOs are similar in many ways to their “high-frequency” counterparts, except they have been specifically designed to operate at slower frequencies. This makes them really useful for creating subtle changes in your patch over the course of seconds or even minutes.

Both Low-Frequency Oscillators in the Dual LFO are identical, so the panel offers “A” and “B” versions of each of the following controls:

• Frequency Knob: Use this to adjust the frequency of the LFO. Lumen’s LFOs can be set to cycle anywhere from 10Hz (10 times a second) all the way down to 0.002Hz (once every 8 minutes)!
• Skew Knob: Lumen’s LFOs oscillate to create triangle waves, but this knob lets you tilt them “to the left” or “to the right” to create ascending or descending sawtooth waves as well.
• Out Port: The LFOs generate control signals, not video signals. This means that their output can be patched to any video or control input, like the ones on the Transform effect.
• Mod In Port: LFO A and LFO B also support frequency modulation. Patch a control signal into the appropriate port to automatically change their frequencies.
• Mod Amt Knob: Controls the direction and amount of frequency modulation from the Mod In port. Note that this knob is bipolar (left is negative, right is positive). It starts at 0, which means no modulation.
• Reset Port: When the signal that is patched in here goes higher than an internal threshold (just over halfway), the LFO will reset its phase, starting its cycle over immediately.

Pro Tip Remember that you can hold Control while turning knobs to fine-tune them. This is really useful for dialing in the perfect LFO frequency!

The final control is the Free/Linked Button, which can be found in the top-right corner of the Dual LFO interface on the Patch Panel. This switches the Dual LFO between two modes:

• Free: Each LFO operates independently. This is the default mode.
• Linked: LFO B is locked to the frequency of LFO A ( ). In this mode, LFO B’s Frequency Knob now controls the phase of LFO B relative to LFO A, instead of LFO B’s frequency:
  • At 0% and 100%, LFO B’s phase is the same as LFO A.
  • At 50%, the LFO B is perfectly out-of-phase with LFO A.

Note that in Linked Mode, each LFO’s Skew, Mod, and Reset controls and ports are still independent.

Patch Ideas

Quadrature-ish LFO

This patch is great for generating related modulation signals that are out-of-phase with each other:

• Linked Mode: Put the Dual LFO in Linked Mode by pushing the Free/Linked button on the Patch Panel interface.
• Frequency B: 50%. This control now sets the phase of LFO B, so set it to halfway, so the LFOs are perfectly out-of-phase with each other. Once you get it all patched up, it’s fun to play with different phase offset settings.
• Patch: Try patching each LFO’s Out signal into a different input, such as the Offset X In and Offset Y In on the Transform effect. (Remember that you’ll have to turn the Offset X and Y knobs away from their default positions on the front panel to see any effect.)
• Frequency A: Set this to taste - it now controls the frequency of both LFOs.

Chaotic Modulation Source

Since both LFO A and B support Frequency Modulation, we can have them modulate each other, creating a pseuod-random slow-moving signal:

• Patch: Out A to Mod In B
• Patch: Out B to Mod In A
• Mod Amt A: Turn away from the middle
• Mod Amt B: Turn away from the middle

Now adjust the frequencies and mod amounts to your liking, and now you can use the signals at the LFO A and B outputs as an unpredictable control signals.

Log / Exponential Curves

Because of the magic of Frequency Modulation, LFO A & B aren’t actually limited to triangle and saw waves - when their output is patched back into their own Mod In, they can generate exponential and logarithmic curves as well:

• Patch: Out A into Mod In A
• Mod Amt A: For an exponential curve (one that spends only a little bit of time “high”), turn the Mod Amt A knob to the right. For a logarithmic curve (which spends a lot of time “high”), turn the Mod Amt A knob to the left. The more you turn it, the more “bent” the generated wave is.

Out A will now generate an exponential or logarithmic curve! Keep in mind that the the Mod Amount will also affect the LFO’s frequency, since we’re patching it back into itself.

Note that the above also works great for LFO B.

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External Connections

This submodule is provides a way to feed multiple external video streams into Lumen. Both Aux In A and B operate the exact same way as the Camera submodule - use the dropdown to select your input source, and the LED will light up when the port is in use.

Pro Tip Be aware that having a video source selected uses up your computer resources, even when you aren’t using it! Therefore it’s best to select “None” from the dropdown when you aren’t doing anything with the signal.

It’s only accessible via the Patch Panel.

Patch Ideas

Multi-Cam External Feedback

Really similar to the “External Feedback” patch idea listed in the Camera submodule’s section… But with more cameras! Get two external webcams and select them from the Aux In A and Aux In B dropdowns. Use them both in your patch, and then point them both back at a screen or TV that you have going full-screen at different angles.

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Kaleidoscope

We love the Kaleidoscope submodule! It’s only got one knob, and yet it does so many things:

• K. Scope: this knob (located under the “Effects” submodule interface on the front panel) controls both the input angle and number of divisions of the Kaleidoscope effect. The knob is multi-turn, which means that you can keep turning it and turning it, up to 16 times! Each time it is turned increases the number of divisions in the effect, starting with none.
• In Port: patch the video signal you want to be affected in here.
• Out Port: the affected signal comes out here.

Pro Tip Remember that you can hold Shift while turning knobs to snap to pre-defined values. Use this to get to exact divisions and angles with the Kaleidoscope.

Patch Ideas

Fractals

1. Start a new patch (Command+N or File -> New)
2. Turn up the Mod on each Oscillator to about 40%. It doesn’t have to be exact.
3. Turn up the K. Scope to a setting more than 3 divisions
4. Turn down the Scale knob just below its default setting
5. Adjust Rotation, Wave Shape, Colors, and Mix Level to taste

Spare Rotation Effect

If the K. Scope is set to less than 1 division, you can use it to rotate video signals. This is really handy when the Transform submodule is already being used for something else.

Geometric Shapes

Check out the tutorial in the Effects guide.

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LFO C

This submodule is the much simpler cousin to the Dual LFO submodule. Unlike LFO A and LFO B, it only generates sine waves. It only has two controls:

• Out Port: Take the sine wave output from here.
• Freq: Sets the frequency of the LFO. The range is the same as the Dual LFO - from 10Hz (10 times a second) all the way down to 0.002Hz (once every 8 minutes).

It is accessible only from the Patch Panel.

Patch Ideas

Auto-Crossfade

LFO C is the perfect thing to use to create smooth crossfades back and forth with it’s neighbor to the north, the Crossfader submodule.

• Patch: One video signal into Crossfader In A.
• Patch: Another video signal into Crossfader In B.
• Patch: LFO C Out into Crossfader Control In.
• Crossfader Fade Knob: Turn all the way to the right to fade 100% between the two sources.

Now the video signal at the Crossfader Out port will be crossfading back and forth, forever. For bonus points, try this patch idea with with two input signals that use feedback from the Master Out - it looks awesome!

Resetting Dual LFO

By patching LFO C’s output into the Reset A or B ports of the Dual LFO, you can create modulation signals that have hard edges, or ones that are synchronized with LFO C.

• Patch: LFO C Out into Reset A or B.

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Mixer

This is one of those submodules that seems simple, but actually has a ton of of hidden powers. It’s also got quite a few controls:

• In Ports: (on the Patch Panel) The Mixer’s fundamental job is to take up to three video signals and mix them together in various ways. It has three input ports, each patched by default (“normalled”) to a different Oscillator:
  • In A: Normalled to Oscillator A Out
  • In B: Normalled to Oscillator B Out
  • In C: Normalled to Oscillator C Out
• Mix Level Knobs: (on the Knobs Panel) Located in the lower-right corner of each Oscillator, each of the three Mix Level knobs controls the input level of its corresponding In port. The Mix Level knob for Oscillator A controls the input level for In A, the Mix Level knob for Oscillator B controls the input level for In B, etc.
• Out Ports: (on the Patch Panel) There are three methods the Mixer uses to combine its input signals, each with its own output port:
  • Max Port: Takes the maximum value of all three inputs for each video component (red, green, and blue). So the brightest reds, the brightest blues, and the brightest greens are kept from the inputs. This can result in bright, vibrant colors, or dark muddy ones if you turn the Mix Level knobs down.
  • Layer Port: It’s easiest to imagine that in this mode, the three input signals are “stacked” on top of each other, with A being on bottom, B in the middle, and C on top. The twist is that in this mode, instead of the Mix Level knobs controlling brightness, each one controls a threshold, below which the darkest parts of each input signal are “cut out,” revealing the signal below. It’s kinda crazy, but some great effects can be achieved if you try it out. Just remember - you’ll have to turn down the Mix Level on Oscillator C to see any effect when using the Layer Port.
  • YUV Port: The YUV Color Space is a method of describing colors with three components: Y (luma), U (chrominance), and V (chrominance). All that this mixing mode does is interpret the brightest parts of each input image as one of these components: In A is Y, In B is U, and In C is V. All you really have to know is that when you mix signals in YUV mode, they come out looking retro, psychedelic, and rainbowy!

Patch Ideas

Mixing in Layer or YUV Mode

Since Max is normalled to the Effects section, you don’t have to patch at all to use Max mode for mixing. But if you’d like to to mix using Layer or YUV mode, you need to:

• Patch: From Layer (or YUV) out port to another input.

That’s it! The above screenshot shows how to modify the Default Patch to use Layer-mode mixing. For bonus points, you can try blending multiple Mixer outputs together using the Crossfader.

Framebuffer

Probably my favorite thing to do with the Mixer is to create a framebuffer - that is, a writeable storage for a single video frame. I find myself returning to this patch idea again and again to create new effects:

1. Start a new patch (Command+N or File -> New).
2. Turn down the Mix Level to 0% on Oscillator B (red) and C (blue).
3. Patch Layer both into the Transform In and into Mixer In A:
4. You should see the video on the preview screen freeze! That’s because the signal that is being used for output from the Layer Out is being fed back into In A, creating a perfect loop.
5. Let’s disrupt that loop. Take a video source such as the one from the Camera, and patch it into Mixer In B. You shouldn’t see any change yet, because Mix Level B is still 0%.
6. Slowly turn up Mix Level B until you see something appear over the frozen image. What we’re doing is lowering the threshold above which bright parts of the video signal will be written to the framebuffer.
7. Once you see something appear, move something in front of the camera! You can see that the brightest parts of the image get written to the framebuffer every time Lumen makes a video frame.
8. Adjust Mix Level B to taste. Maybe even add in another input to Mix Level C! Don’t forget to turn it up too.

Fading Framebuffer

To get a framebuffer that slowly fades out to black, first create the above patch and then hold down Control while turning down Mix Level A to around 99.3%. The lower you turn down Mix Level A, the faster the image will fade out.

Spare Trails

You can sacrifice a channel of Lumen’s Mixer to create a Trails effect:

• Patch: Max into In C:

• Mix Level C: Controls the amount of the effect. You’ll only start noticing the effect above 50%. You may need to hold the Control key while twisting the knob to dial in the value that feels right.

For Bonus Points, you can create a Voltage-Controlled Spare Trails Effect by combining this with the Crossfader’s “Fader / VCA” patch idea:

Now you can modify the amount of the effect with a control or video signal!

Feedback Mixer

There’s no rule saying you have to use the Mixer to create the Master output signal… You can also use it to mix signals to create complex feedback. In this patch, I’m using the Mixer to control what amounts of Oscillator A, Oscillator B, and Oscillator C’s signals will get used to modulate Oscillator C:

You’d use the Mix Level knobs to control the amount from each Oscillator.

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Oscillator

Oscillators. Lumen’s got three of them, and they’re so important that we’ve got a whole guide dedicated to them! If you haven’t done so already, please check it out for a great tutorial on how to get started using Oscillators to create moving video patterns in real time.

Internal Architecture

The Oscillator is the beating heart of Lumen. And just like the heart, it’s really complicated, so there’s going to be a lot of stuff to go over here if I’m going to do it justice.

Under the hood, Lumen’s Oscillator is actually made up of several different components connected together internally. The way it works is that the Oscillator takes some Input, and runs it through a Waveshaper, then through and a Colorizer, and then uses the resulting signal as output:

Let’s go through each of those parts one-by-one:

• Input: Which signal the Oscillator processes is chosen with the Input Mode button (the one that can say “Osc” or “Cam” on the Knobs Panel). The options are either to use the signal at the Camera In Port, or use an internally generated saw wave.
• Waveshaper: This component’s job is to turn a saw wave into triangle and sine waves. If the Mod Mode (chosen with the Mod Mode button) is “Phase” or “Key,” the Waveshaper also applies phase modulation to the input signal based on the Mod In signal. Note that the Waveshaper is always operational, even when the Input Mode is “Cam”.
• Colorizer: Whatever comes out of the Waveshaper gets colorized with the hue and saturation settings chosen with the Oscillator’s Color Picker. When the Mod Mode is “Hue,” the hue that is chosen will be modulated based on the Mod In signal.

Whew! That was a bit much. Let’s move on to where those signals come from and how to control them.

Panel Controls

For the completionist in us all, here’s an in-depth description Lumen’s Oscillators’ numerous controls:

• Knobs Panel:
  • Frequency Knob: Adjusts the frequency at which the Oscillator cycles. The inner knob is for fine-tuning, while the outer is for coarse tuning. When unsynced, the minimum frequency is 0.125Hz (once every 8 seconds) and the maximum is 3mHz (3 million times a second).
  • Input Mode Button: Switches the Oscillator’s Input Mode. This tells the Oscillator which signal to use as input to its Waveshaper:
    • Osc: Uses an internally generated saw wave as input. This saw wave is affected by frequency modulation.
    • Cam: Uses the signal at the Camera In port as input. This is normalled to a channel of the RGB Splitter module.
  • Mod Mode Button: Switches the Oscillator’s Mod Mode. The Mod Mode affects not only where the signal from the Mod In port is routed to, but what it does once it gets there. Check out the Modulation guide for a detailed introduction.
    • Phase: The Waveshaper performs phase modulation on the input signal using the Mod In signal as a modulator.
    • Key: The Waveshaper performs phase modulation on the input signal and acts as a Keyer instead of a saw-to-triangle-or-sine shaper. The threshold of the Keyer is set by the Wave Shape knob.
    • Hue: Phase modulation is not performed, but the Colorizer’s hue is modulated based on the Mod In signal.
  • Wave Shape Knob: In “Phase” and “Hue” Mod Modes, this knob controls the degree to which the internal saw wave is transformed into a triangle or sine wave. In “Key” mode, it sets the threshold for the Keyer.

Coming Soon Further description of Oscillator’s panel controls coming soon

Patch Ideas

Each of these patch ideas involves either one or two oscillators, so if you’re using the Default Patch to try these out, remember to turn down the oscillators you aren’t using in the mix.

Noise

• Patch: Oscillator Out into its own Mod In
• Mod Mode: Phase Mod
• Sync: Unsynced
• Frequency: Above 1.2kHz

Solid Color

• Sync: H. Sync
• Frequency: All the way down
• Wave Shape: Saw

Solid Half-Screen

• Mod Mode: Key
• Sync: H. Sync
• Frequency: Around 60Hz
• Threshold: Adjust until there is a square wave that fills half of the screen

To make it vertical, set Sync to V. Sync and lower the frequency.

Ramps

Same as Solid Half-Screen patch idea (above), but change:

• Mod Mode: Phase
• Wave Shape: Saw

To make it vertical, set Sync to V. Sync and lower the frequency.

To make the bright part on the Right/Bottom instead of the Left/Top of the screen, change:

• Wave Shape: Triangle
• Frequency: Adjust to half of the frequency as before

Diamond

This idea involves two Oscillators and the Signal Processor:

• Patch: Oscillator A Out to Signal Processor In A
• Patch: Oscillator B Out to Signal Processor In B
• Patch: Use the signal from Signal Processor’s Out
• Signal Processor
  • Mode: Fade (You can hold Shift while twisting to get it exact)
• Oscillator A
  • Sync: H. Sync
  • Frequency: Around 60Hz
  • Wave Shape: Triangle
• Oscillator B
  • Sync: V. Sync
  • Wave Shape: Triangle
  • Frequency: Adjust until the diamond shape covers the screen

You can make ramps coming diagonally from the top corners by using Saw waves instead of Triangle.

You can create a vignette/spotlight pattern by using Sine waves instead of Triangle.

Freeze Frame

This one is a weird one:

• Wave Shape: Saw
• Input Mode: Osc
• Patch: Oscillator Out to its own Camera In

Now switch Input Mode to Cam, and… It’s frozen!

Slowly turn up the Wave Shape to the ’d frame.

To get a new frame, switch the Input Mode back and forth again.

Tech Note: This patch will not be 100% restored after being saved to the Library. This is because we currently don’t save the signals of the synth, only knob positions and Oscillator phases. Thus, you have to switch the Input Mode back and forth again to capture a new frame after you load this patch from the Library.

Super Advanced: It is possible to freeze-frame a different input source other than the oscillator’s own output – check out the patch from the Preset Library called “Ugh” to see an example of this technique.

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Coming Soon Sections for the RGB Splitter, Signal Processor, Trails, and Transform submodules aren’t finished yet. Stay tuned!

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Congratulations

You’ve finished Lumen’s documentation*!

*Except for the Appendix, but who counts that??