#eulumdat

Definition of planes in C-gamma coordinates

Axel Stockmar's EULUMDAT file format is an industry standard, but not a well described one. I'm confused especially by the files with symmetry on the C90-C270 plane. These are most often used in road lighting. The AGI32 knowledge base, probably mostly authored by Ian Ashdown, ...

Hello, I am currently doing some work research on IES/LDT format in the context of game lighting simulation. However I found the IES format pretty confusing and wanted to clarify thing with expert in this list. I know for sure that LDT use candela / kilolumens unit for ...

Working intensively with both IES and EULUMDAT files as creator of the free online conversion tools at httip://ies2eulumdat.appspot.com, I have encountered most problems with the conversion of the luminous area data. EULUMDAT has facilities for defining a circle, rectangular, ...

QLumEdit (v 1.0.1 right) and DIAL LDTEditor (v 1.1.0.3, left) disagree on sequence of C-planes in EULUMDAT with symmetry over C90-C270. 

DIAL LDTEditor (left) and QLumEdit agree on display of EULUMDAT files with symmetry over C90-270 (first) but disagree on display of files with no symmetry (second). Why is this so confusing?  

Relux says the first dataset is the C270/C-90 dataset, the larger set and last one in the ELUMDAT file is the C90 set. As above C90 is always larger value than C270 column.

Asymmetric plane C90-C270 has most output towards the C270 side, AWAY from the road surface!