Summary #
Simulations layer on top of an Illumination channel’s existing curve, automatically adjusting its brightness based on the season, weather, or moon phase. Several simulations can be active on the same channel at once — the resulting brightness is calculated from all of them combined. Each simulation must be enabled per channel before it has any effect, with its own parameters configured separately under Illumination → Simulation, Illumination → Thunderstorm, or Illumination → Seasonal lighting.
Applies to #
- Mitras Lightbar 1-3
- Mitras Slimline
- Mitras LX8 Series
- Mitras LX7 Series (incl. Industrial Line / IL)
- Mitras LX6 Series
- Compatible controller:
- ProfiLux 4 Series (incl. Industrial Line / IL)
- ProfiLux 3 Series
- ProfiLux Mini / Light (all versions)
- Software:
- GHL Connect (App, Webinterface, myGHL)
- GHL Control Center
Before you start #
- An Illumination curve should already exist: Simulations modify an existing brightness curve rather than creating one. See Lighting Schedules – Configuration Guide if you haven’t set one up yet.
- Each simulation needs enabling per channel: Every simulation below has its own checkbox or toggle on the Illumination channel it should affect — see the Channel Settings section of the Lighting Schedules article. The settings described below are the simulation’s own parameters, configured separately from that per-channel toggle.
Simulation #
Clouds, Moon Phase, and Rainy Days share a single settings page. Open it via Illumination → Simulation.
Clouds #
Clouds briefly and randomly darken a channel, simulating drifting cloud cover.
- Max. pause: The longest the random generator can wait before starting a new cloud — set to 0 to disable the simulation entirely.
- Min. duration / Max. duration: How long an individual cloud lasts, randomized within this range.
- Max. darkening: How dark a cloud can make the channel at its peak.
For multiple fixtures, the Timeshift – During clouds setting on each Illumination channel (see Lighting Schedules) lets you offset when each one responds, so a single cloud appears to drift across them one after another instead of darkening everything at once.
Moon Phase #
Moon Phase calculates a lunar brightness value based on the date and applies it to any channel with moon simulation enabled.
- Min. brightness (new moon) / Max. brightness (full moon): The brightness range the moon phase is calculated within.
- Full moon also at: A reference date used to align the simulated cycle with the real lunar calendar — the default works well for most setups, so you’d only change this to deliberately offset the simulation.
- Average moon phase duration: The length of one full lunar cycle in days — the default works well for most setups.
A mode choice then determines how this brightness actually affects a channel:
- Basic mode: Within a set time window, every channel with moon simulation enabled has its curve brightness multiplied by the current moon brightness — so the channel still runs its normal curve outside that window, and only takes on moonlight characteristics during it. For example, a curve value of 50% combined with a half-strength moon results in 25% during the set window. Set a Start time and End time for the window.
- Advanced mode: Hands a channel over to the moon simulation permanently — its own curve no longer has any effect, so the channel can only act as a moon light. The configured brightness range (Min./Max.) becomes the channel’s actual output range, varying with the lunar cycle rather than being multiplied on top of a curve. Set a Daily moonshine duration and the time the Full moon is at its zenith, around which that duration is centered. Shift zenith time dependent on the moon phase additionally simulates how the real moon’s peak time shifts across its cycle.
A live display shows the current moon phase and brightness, including a graphical representation of the phase.
Rainy Days #
Rainy Days reduces a channel’s brightness by a fixed amount on chosen days of the week, simulating an overcast day.
- Darkening: How much the brightness is reduced on the selected days.
- Rainy days at these days only: A checkbox for each weekday (each abbreviated to a single starting letter in GHL Control Center) for which days the reduction applies.
Thunderstorm #
Thunderstorm simulates an approaching and receding storm: channels gradually darken while flashes become more frequent, build to a climax, then recover as the flashes taper off. Open it via Illumination → Thunderstorm. In GHL Connect, this is split across a Thunderstorm Schedule tab and a General tab; in GHL Control Center, everything sits on one page, with the schedule at the top.
Schedule #
- Weekdays: Which days automatic storms are allowed to occur.
- Storms per day (GHL Control Center only): Activates that many of the four storm slots, Thunderstorm 1–4, each with its own start time and duration.
- In GHL Connect: Instead of numbered slots, a table lets you add up to 4 entries — start time and duration are set in a modal when adding. Edit or delete an existing entry via its gear icon.
Thunderstorm Settings #
- Intensity: Higher values generate more frequent flashes during the storm.
- Darkening: How dark the channels get during the storm.
- Flash brightness: The LED output during a flash.
Random Thunderstorms #
Random storms can run instead of, or alongside, the schedule above — they occur automatically with a pause randomized between a minimum and maximum waiting time.
- Duration: How long a random storm lasts.
- Min. waiting time / Max. waiting time: The range the next random storm’s start is drawn from.
Manual Triggers #
- Manually started thunderstorm: Enter a duration and press Start to run a full storm immediately, using the Intensity, Darkening, and Flash brightness configured above — useful for testing how a storm will actually look.
- Trigger flash manually: Flash 1, Flash 2, and All flashes buttons trigger a single flash without starting a full storm.
How flashes are output depends on the connected lighting: on Mitras Lightbars and Mitras LX, the flash channels are fixed and handled by the lamp itself — there’s no per-channel configuration needed or possible. On 1-10V outputs, flashes are controlled by briefly setting the output to the configured flash brightness value. Some programmable 1-10V devices such as the LEDControl4 V2 allow partial flash configuration. Lights connected via switch channels can respond to flashes too, by assigning the Thunder function to the channel — it switches on briefly with each flash.
Seasonal Lighting #
Seasonal Lighting adjusts an existing curve’s brightness and duration over the course of the year, similar to how daylight changes with the seasons in nature. Open it via Illumination → Seasonal lighting. A usable default course is already stored, so it works out of the box — the sections below describe how to review, adjust, or fully replace it. In GHL Connect, settings and charts are split across a Settings tab and a Chart tab; in GHL Control Center, the charts sit inline among the settings.
Yearly Course #
A table holds up to 24 entries. Entries are added, edited, and removed via the +, pencil, and trash icons plus double-click in GHL Control Center; via the Add button and gear icon (with Delete in the detail dialog) in GHL Connect. Each entry defines:
- Date: Day and month of this entry.
- Brightness of this day (compared to the longest day) — shown simply as Brightness in the table — reduces the lighting on days set below 100%.
- Duration of this day (compared to the longest day) — shown simply as Duration in the table — reduces how long the channel’s curve runs that day.
Values for the days in between are calculated automatically, giving a smooth transition across the year rather than abrupt jumps.
Midday (called Midday shall be at this time in GHL Control Center) sets the anchor time used when Duration shortens a day — each point’s distance to this time is scaled proportionally. For example, with Midday at 12:00 and a curve normally running from 08:00 to 20:00, a 50% Duration would result in 10:00 to 16:00.
Fill Table Automatically #
A default course is already preset, but you can quickly regenerate the whole table instead of entering all 24 days by hand:
- The longest and brightest day should be at: The date (day and month) this peak falls on — defaults to the summer solstice, with guidance shown for the northern and southern hemisphere.
- Brightness of the shortest day (compared to the longest day): The minimum brightness point of the year.
- Duration of the shortest day (compared to the longest day): The minimum duration point of the year.
- Fill table now: Calculates and fills the full 24-day table from the three values above — the longest day is automatically set to 100% for both Brightness and Duration.
Testing #
GHL Control Center only: pick a date under Simulate for this day and press Simulate now to preview the result — it’s overlaid as a dashed line on the affected Illumination channels’ curve, so you can check a specific date before it actually runs.
Charts #
Two charts, stacked — Brightness and Duration, each showing that value’s course across the year based on your configuration. Both can be edited directly via drag-and-drop or by clicking a point, the same as an Illumination channel’s curve.
Use large variations with care — significant swings in duration or intensity can stress corals or plants and destabilize the system.
Notes & Troubleshooting #
- Multiple simulations can be active on the same channel simultaneously — the resulting brightness combines all of their effects on top of the curve, not just the most recent one.
- If a simulation doesn’t seem to affect a channel, check that its checkbox or toggle is actually enabled on that Illumination channel — the simulation’s own parameters (described above) only take effect once it’s switched on per channel.