Lighting and control
Optics, distance and coverage
Estimate initial coverage and check useful light against model-specific photometry.
Ask GLMedia about a lighting rental solution for your event, subject to availability and technical requirements.
Using this guide
Measure optical throw to the target, not support height alone. An angled surface changes footprint shape and distribution.
Prepare your rental inquiry
- Date, city, venue and setup, event and pickup schedule.
- Intended use, area dimensions and equipment already supplied by the venue or production.
- Approximate target width and depth; possible fixture position and height, and estimated throw to the area. Note any angled surfaces or obstructions.
- What you want to highlight and what should remain outside the light; photos or a sketch and placement restrictions if available. Mark measurements as provisional to start the inquiry and identify what still needs a site survey.
Specify equipment only or whether setup, programming, operation and strike are also needed. Scope is confirmed in the proposal.
You do not need a final equipment list: tell us the result you want and the part you need help with. Availability and scope are confirmed in the proposal.
Features and connections
Fixed lens, zoom, focus and shutters serve different purposes. Photometry must match fixture, optics, color and settings.
Start with the positions the venue allows and the surface you want to light. Compare each position with the target width and depth using the relevant photometry. If a position does not work, consider another optic, another approved position or several lighting points; the result needs verification. Approximate dimensions and a photo or sketch showing the target and possible positions are enough to start a proposal without choosing a model first.
Prepare the system
- Define target width, depth and required level; record position and aiming.
- Geometric example, D = 2 × d × tan(θ/2): at 5 m with a full angle of 30°, diameter is approximately 2.68 m on a perpendicular plane for an ideal circular cone.
- Confirm the datasheet’s angle definition; compare distribution and lux, then test overlap and edges. The example promises neither uniform coverage nor brightness.
Questions and troubleshooting
Does it open wide enough but deliver too little light?
Coverage and illuminance are separate checks.
- Consult lux at the selected distance and setting; measure center and edges using the actual scene.
- Check losses from color, diffusion and framing before changing distance or fixture.
Are the edge or gobo out of focus?
Zoom changes size; focus sets sharpness when the model provides both.
- Test focus on the target and verify lens, installation and supported range.
- Adjust shutters or iris afterward; do not confuse a soft-edged wash with a poorly focused profile.
Are there gaps or hot spots between fixtures?
Geometric diameter does not define uniform spacing.
- Compare intensity profiles and overlap on the actual area; check the movement limits too.
- Adjust aiming and levels with measurement and camera where applicable; do not multiply diameter by fixture count to guarantee area.
Precautions
- Lumens describe flux; lux describes surface illumination. They are not interchangeable without geometry and distribution.
- Do not transfer photometric curves between lenses or models; actual output may vary between units.
- Follow manual minimum distances, attachments and optical retention requirements.
Documentation and sources
Accessed: 2026-10-22. Calculated example and proposed checks; no GLMedia physical testing.
Guides to plan your system
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