IES Viewer for Fast IES File Checks

This IES viewer helps you review an IES file quickly before you commit to a full lighting plan. Upload the photometric file and use the results to understand the distribution, intensity behavior, and what the fixture will do in a real room.

If you are an architect, engineer, contractor, or lighting designer, this tool gives you a clean first pass. It is ideal for early layout decisions and fixture comparisons.

Downlight Spacing Calculator Using Real Photometric Data

A spacing rule of thumb is not enough when beam angles, lumen packages, and mounting heights change. This calculator uses the IES file as the source, so your spacing estimate matches the fixture’s real distribution pattern.

• Use the IES viewer to confirm you have the correct photometric file.
• Set the ceiling height and the workplane assumption (typical interiors use a workplane around desk/counter height).
• Adjust spacing and layout until the coverage looks balanced.
• Compare multiple fixtures by uploading different IES files.

What to watch for when using an IES viewer

• Narrow optics: tighter beams often need closer spacing to avoid scallops and dark gaps.
• Wide optics: can reduce fixture count, but may create glare if the cut-off is poor.
• Mounting height: higher ceilings usually increase spacing, but uniformity can drop if spacing is pushed too far.
• Ceiling reflectance and room finishes: this tool gives a first approximation. Final performance depends on surfaces.

What This IES Viewer Does and Does Not Do

This IES viewer is built for speed and early design decisions. It helps you understand distribution and spacing directionally. It does not replace a complete photometric calculation for permits, inspections, or performance guarantees.

• Good for: quick fixture checks, early spacing, concept layouts, comparing distributions.
• Not a replacement for: full photometric plans with target light levels, uniformity ratios, and code-driven requirements.

Need a Permit-Ready Photometric Plan?

If you are submitting drawings for review, or you need verified foot-candle (fc) / lux levels and uniformity, we can help. Stetra Lighting produces professional photometric plans for interiors, parking lots, warehouses, and sports fields.

Order a Photometric Plan or review our service options here: Lighting Services.