The majority of lighting fixture manufacturers are currently employing the Illuminating Engineering Society (IES) standard recommended file format for luminaire photometry (IES document LM-63-02).
The ASCII file format is shown below. This is exactly how any IES format file should appear when listed directly from a text editor. The standard for this format is included in the document LM-63-02, available from the Illuminating Engineering Society (www.ies.org).
IES File Format
Each line marked with an asterisk must begin a new line. Descriptions enclosed by the brackets"<" and ">" refer to the actual data stored on that line.
All information is in standard ASCII format.
IESNA:LM-63-2002
<keyword 1> <keyword data>
<keyword 2> <keyword data>
:
<keyword n> <keyword data>
TILT=<filespec> or INCLUDE or NONE
<lamp to luminaire geometry>*
<# of tilt angles>*
<angles> *
<multiplying factors>*
<# lamps> <lumens/lamp> <multiplier> <# vertical angles> <# horizontal angles> <photometric type> <units type> <width> <length> <height>**
<ballast factor> <future use> <input watts>
<vertical angles>
<horizontal angles>
<candela values for all vertical angles at first horizontal angle>
*<candela values for all vertical angles at second horizontal angle>
:
<candela values for all vertical angles at last horizontal angle>
* The four lines following the TILT line here are used if and only if TILT=INCLUDE.
** The terms width, length and height are measured in the Y, X and Z directions, respectively, and refer to the luminous dimensions.
NOTE: At the time of release of this publication, some luminaire manufacturers do not employ the IES LM-63-02 keyword scheme. Lighting Analysts programs do not require the LM-63-02 keywords; however, the AGi32 Instabase uses keywords if present. Without keywords, all information preceding the TILT= line is read as descriptive information.