Compare Tool Report Setup

The Compare Tool report Setup dialog allows you to select which metrics to include in your comparison from a list of available Report Categories. Most of the metrics shown in this Tool are also available in Photometric Toolbox's Road, Flood and Indoor Reporting Tools. There are a few metrics that only appear in this tool, such as Upward Waste Light ratio (UWLR), Glare Zone Flux 80-90, and Glare Zone Max Intensity 80-90.

Available Report Categories

The Available Report Categories drop down list provides a method for filtering which metrics are available for selection. By default, All metrics are shown. The Filtering options include, Indoor, Roadway and Flood. In each selection set, the metrics are displayed in alphabetical order.

Selecting Metrics

To select a metric, simply select the checkbox adjacent to the metric name. As soon as a metric is selected, it will appear in the Current report Template list on the right side of the dialog. To remove a metric, simply deselect it from either list.

Metrics are always added to the bottom of the Report Template. You may move a single metric at a time  up or down in the list by using the Move Up and Move Down buttons (Shortcut + and - keys).

Saving a Report

To create a new Report Template, simply choose the metrics you wish to include, enter the Report Name in the Current Report Template field, then click the Save button. To see the Report applied, click Apply or Ok.

Reset Reports

Pressing the Reset button, resets ALL reports to factory settings. Any user modifications are lost.

Normalize Distributions to Same Total Lumens

This section allows you to specify an alternate Total Lumen value (or Luminaire Lumens for absolute photometry) for all currently selected photometric files. When the Total Lumen value is applied, the candela values are also normalized within each photometric file to allow an apples to apples comparison.

When should this metric be applied? One example would be to normalize the Total Lumens for area lighting luminaire types with vertical lamp lumens specified erroneously instead of horizontal lamp lumens (for HID lamps). Another example would be to normalize the Total Lumens to 1000, to view the relative performance across a variety of possible lamp options.

Compare Metrics (some not defined in other Reporting Tools)

Glare Zone Flux (80-90) - Defined as the luminous flux (as a percentage of total lamp lumens) in the glare zone.

Glare Zone Max Intensity (80-90) - Defined as the maximum intensity (as a percentage of the total lamp lumens) in the glare zone.

Both metrics are defined per the National Lighting Product Information Program (NLPIP) Parking Lot and Area Luminaire Specifier report. NLPIP is administered by the Lighting Research Center (LRC). The metrics do not serve to introduce new lighting metrics, their purpose is to allow more thorough evaluation of luminaire performance within the IES Cutoff Classification range.

UWLR - Upward Waste Light Ratio (ULWR) calculates the proportion of the luminous flux emitted by the luminaire above the horizontal. The metric was developed by the Joint Standards Australia/Standards New Zealand Committee LG/2, Road Lighting and is published as document AS/NZS 1158.1.1:1997 Road lighting.

UWLR = ULOR / LOR, where

ULOR = Upward light output ratio of the luminaire

LOR = Total light output ratio of the luminaire

LER - Luminaire Efficacy Rating (LER) measures a luminaires efficiency and efficacy together in a single metric. At the current time, it has only been validated for indoor luminaires described by NEMA. The luminaire product category is not reported by PTB, only the LER value, as the product information is not extractable from the IES file. More information is available here.

LER = [ luminaire efficiency (EFF) x total lumens (or luminaire lumens with absolute photometry) (TL) x ballast factor (BF)] divided by [luminaire watts input] ]

LCS - The Luminaire Classification System (LCS) is the successor to the now deprecated Cutoff classification, and reports the zonal lumens and percentages within each of 10 zones as defined by the IESNA as significant. Specifically, the zonal lumens are reported for 4 forward zones, 4 backward zones and 2 uplight zones. LCS is an IESNA metric documented in document TM-15-11. More information is available here.