Photometrics for Commercial Lighting

Commercial photometrics for specification, verification, and field execution

Engineer reviewing a photometric lighting layout on a tablet showing a point-by-point grid and isolux contours for a commercial site plan.
Photometric layouts translate IES data into predicted light levels and uniformity for real project conditions.

Quick answer: Photometrics translate a fixture into predictable site performance. For commercial projects, the most common deliverables are IES files (for software modeling) and layout results (average/minimum footcandles, uniformity, and point-by-point grids). If you need photometric support, share mounting height, area dimensions, target light levels, and constraints such as glare or light trespass.

Units note: Results are commonly provided in footcandles (fc) in the U.S. and lux in many specifications—confirm which unit your team expects.

Planning note: Photometrics are only as accurate as the fixture selection and configuration used in the model. If you’re still finalizing fixture type, optics/distribution, mounting height assumptions, or compliance-driven constraints, start with the relevant buying guide before you request a layout:

What photometrics are

Photometrics describe how a luminaire distributes light in the real world. For commercial projects, photometric data is used to predict performance before purchase and installation—helping teams confirm target light levels, uniformity, glare control, and spill/light trespass risk.

  • IES file: a standardized photometric data file used by lighting calculation software.
  • Point-by-point grid: a table of calculated light levels across a defined area.
  • Average and minimum: summary values used to evaluate coverage and dark spots.
  • Uniformity ratio: typically expressed as avg:min or max:min, used to assess consistency.
  • Mounting height and spacing: the two inputs that most strongly influence results.

Buying guide tie-in: If your team is still deciding fixture category or optics/distribution (which changes the IES file you should use), start with the right guide and lock selection before running the model:

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Photometric deliverables (what teams request)

Commercial project teams typically request one or more of the deliverables below depending on the stage of the project.

Photometrics deliverables showing IES files, point-by-point grid, average and minimum light levels in footcandles or lux, uniformity ratio, and optic or distribution notes.
Common photometric deliverables used for review, documentation, and layout verification.
  • IES files for modeling and project documentation
  • Layout results (average/minimum light levels and uniformity)
  • Point-by-point grids for verification and review
  • Fixture spacing guidance based on mounting height and target levels
  • Optic/distribution selection guidance (application-driven)

Scope note: Photometric results depend on project inputs (area geometry, mounting height, aiming, tilt, obstructions, and surface reflectances). Confirm the assumptions match the field conditions before relying on results.

Helpful references (by application): These buying guides support the two most common “deliverable gaps” in photometric requests—mounting-height assumptions and distribution/optic selection:

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What we need from you

To support a photometric request efficiently, provide the inputs below. If you don’t have all details, send what you know and mark unknowns as “TBD.”

  • Application: parking lot, building perimeter, canopy, warehouse, corridor, etc.
  • Area dimensions: length × width and any no-light zones or setbacks
  • Mounting height: measured above finished grade/floor (or above deck for canopies)
  • Fixture locations (if known): spacing or a simple sketch / plan
  • Target light levels: average and minimum requirements (if specified)
  • Constraints: glare control, light trespass limits, dark-sky rules, neighbor setbacks
  • Electrical/controls: if it affects fixture configuration or output settings

Buying guide tip: If you’re unsure which fixture category to model, reference the guide that matches the space. It prevents running the wrong family/distribution and having to redo the layout:

Document handling note: The form does not support file uploads. Email drawings/plans to support@starsandstripeslighting.com after submitting your request and include the project name + location in the subject line.

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Review checklist for layouts and results

Before accepting a layout, review these items. Most layout issues come from incorrect assumptions, not bad products.

Review checklist for photometric plans covering mounting height, area boundaries, fixture count and spacing, optic or distribution, minimum and average light levels with uniformity, and project constraints.
Before approving a layout, confirm assumptions match field conditions and results meet minimum and uniformity expectations.
  • Mounting height: matches actual field height
  • Area geometry: dimensions and boundaries are correct
  • Fixture count and spacing: matches install intent
  • Optic/distribution: matches the application and aiming direction
  • Results: average, minimum, and uniformity meet expectations
  • Constraints: glare/light trespass considerations are accounted for where required

Where guides help in review: If a reviewer is questioning beam angle, distribution type, or mounting-height assumptions, reference the relevant guide to validate the layout logic (and reduce revision cycles):

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Common pitfalls that cause rework

  • Wrong mounting height: even a small change can materially alter average/minimum levels.
  • Unstated constraints: trespass limits, aiming restrictions, or shielding requirements not communicated early.
  • Unknown fixture configuration: selectable wattage/CCT or optic options not locked for the model run.
  • Ignoring obstructions: canopies, parapets, equipment, or structural elements affecting distribution.
  • Using the wrong metric: average-only decisions that ignore minimums and uniformity.

Prevention: Most rework happens when the wrong fixture category or distribution is modeled. These buying guides help lock selection before the photometric run:

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How to request photometric support

Use your quote intake form and include “Photometrics” in the message. Provide the inputs from the “What we need from you” section. If you have drawings or plans, email them to support@starsandstripeslighting.com after submitting the form so we can match them to your request.

Helpful (reduces revisions): If your selection is based on one of our buying guides, mention which one so we can model the correct category and assumptions:

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If you’re using photometrics for compliance, layout verification, or closeout documentation, these guides help your team standardize inputs and interpret results.

Buying guides (selection + assumptions): Use these when the team needs to validate fixture category, mounting-height logic, beam angles, or distribution type before approving the model:

Note: For indoor-only photometrics, the surge protection link may be optional. Keep the photometric report + controls links as the most universally useful references.

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Frequently asked questions

What is an IES file?

An IES file is a standardized photometric data file used by lighting calculation software to predict light distribution and results across an area.

Do photometric results guarantee field performance?

Photometric results are predictive and depend on the assumptions used (mounting height, locations, aiming, and geometry). Confirm the model inputs match the field conditions.

What inputs matter most?

lMounting height, fixture count/spacing, and the selected optic/distribution typically have the biggest impact on average, minimum, and uniformity.

Which buying guide should we reference before requesting photometrics?

Use the guide that matches the application so the correct fixture category and assumptions are modeled:

How do we send drawings if the form has no upload?

Email drawings or plans to support@starsandstripeslighting.com after submitting your request, and include the same name and email used on the form.

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These pages cover the adjacent workflow steps that commonly feed into photometric requests, submittals, and closeout documentation.

Specification and planning guides: If selection and assumptions are still being finalized, these guides help lock the correct fixture category before photometrics, submittals, and closeout requests:

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