Candelas Lumens and Lux book logo
Candelas Lumens and Lux
By
Owen F Ransen
     
 

 

 

 

Candelas Lumens and Lux is a very brief introduction to the basic ideas and math of illumination engineering.

How to get "Candelas Lumens and Lux"

Table of Contents:

  1. Candelas, Lumens and Lux
  2. Luminance
  3. Photometries
  4. Internal Lighting
  5. Glare
  6. Roadway Lighting
  7. Light sources and Efficiency
Candelas Lumens and Lux book

The book, which costs $19.99, has 146 pages, half of which are diagrams. Below is a PDF file which contains the first two pages of each chapter in the book:

PDF sample of the book: "Candelas Lumens and Lux"

I decided to use tons of graphics because it is the more immediate way of explaining the subject. We are talking about light after all! Here is a sample of the graphical explanations in the book:

Candelas Lumens and Lux sample diagrams

When you get to the end of the book you will understand the difference between "Candelas, Lumens and Lux", and have a clear idea of other important lighting concepts.

Buy "Candelas Lumens and Lux"

The book can be used as a self study course on lighting terminology and calculations, as well as the basis for a class course.

Chapter 1 is about the three main units used in lighting specification and calculation: Candles (luminous intensity), Lumens (flux, or quantity of light) and Lux (illumination on a surface).

Candelas as rays of light of varying lengthsIllumination of a surface

Chapter 2 is about Luminance, (very roughly the appearance, "brightness", of objects), including the luminaires themselves (and their light emitting surfaces) as well as objects and worksurfaces illuminated by them:

Luminance, Candelas and Lux

 

Chapter 3 shows you how to read photometric diagrams, both C-Gamma and VH diagrams:

How to read VH diagrams

Chapter 4 explains the basics of internal lighting, and how to calculate the number of luminaires of a given type for a certain sized room using the Room Index and Lumen Method:

How many luminaires for this room?

Chapter 5 explains how a Sollner diagram and luminaire glare are related, and how to interpret the UGR (Unified Glare Rating) number and table. A simplified Sollner diagram is shown below along with the polar diagram for the same luminaire...

Sollner diagram compared with Polar Diagram

... and its usefulness as well as its limitations are explained in the book.

Road lighting is covered in some detail in chapter 6. For example why do most luminaires designed for roads have wide wings in their photometric diagram? Look at this photometric diagram:

Road Lighting Polar Diagram. How to understand photometric polar diagrams

(A clue: the red "wings" shoot light up and down the road, and the blue curve shoots light...where?)

And how do you interpret a road lighting utilization diagram? Here's one:

Road Lighting Efficiency Diagram

A clue: We are looking at the luminaire "side on" the left half is the side-walk, the right half is the..?

The book has complete answers, and more:

Where to buy "Candelas Lumens and Lux"

"Candelas Lumens and Lux" covers the subject for visible light, using concepts for photometry rather than for radiometry. Radiometry covers the whole electromagnetic spectrum, whereas photometry considers only the visible spectrum. There is an brief description of the spectra of the 'standard' eye and the luminaire and how they relate to each other in Chapter 7.

Here is one of the illustrations from that chapter:

Candelas Lumens and Lux illustrattion sample

Here is a partial index of the book:

analysis of glare
angle of incidence
apparent area
apparent brightness brightness
British Glare Sensation
C-Gamma
C-Plane
Sollner and Glare
C90 plane and road lighting
C180 Sollner and Glare
Candelas
car park lighting
cartesian (for VH)
Cavity and frieze
cd
cd/klm
ceiling cavity
classroom lighting
cone of vision
contrast
cosine
cubed rule diagram
direct lighting
direct lighting room index direct-indirect
Disability glare
Discomfort glare distribution (road lighting)
DLOR
Downward Light Output Ratio
E=illumination
Efficay
Efficiency vs Efficacy
electrical power energy
eye
eye responds logarithmically
factory lighting
Fat Room Index
FFR
floodlights
flux
flux fractions
frieze frieze and cavity
gamma
glare
glare formula
Glare Index
glare quality class
Guth Index
horizontal illuminance
Hospital Lighting
illuminance

Illuminance is additive
illumination
indirect lighting
intensity
iso-candela diagrams
isolux
isolux diagram
K (room index)
kcd
kilo-lumen
kilocandela
kilolumen
klm
Lambertian
lamp flux
LFF
Light Output
Light Output Ratio
lm logarithmic response (eye)
Long Distribution
LOR
Lumen Method
Lumens
lumens per watt
luminance
Luminance
Luminance the formula
Luminous efficacy
luminous efficiency
luminous flux
luminous intensity
lux Lux
lx
Maintenance Factor
Matt surfaces
Medium Distribution
MF
MH
Mounting Height
moon
Mounting Height (Roads)
narrow beam
normal
ocular media
Office Lighting
omega
perfectly diffuse surface
photometric
photometric brightness
photometric diagram
photometric solid
polar diagram
polar photometric diagram
position index
radiant energy
reflectance
Reflected light
retina
rho
reflectance
road lighting
road lighting classifications
room index
Short Distribution
SHR
solid (photometric)
solid angle
Sollner diagram
Spacing to Height Ratio
spectrum
sports field
spread
stadium lighting
steradian
sum of the illuminances
sun
Throw
Total Flux Method
tunnel
Type (Roads)
Type I (road lighting)
Type II (Roads)
Type III (Roads)
Type IV (Road lighting)
Type V (Road Lighting)
UF (Utilization Factor)
UFF
UGR
UGR table
ULOR
Unified Glare Rating
uniformity
Upward Light Output Ratio
Utilization Coefficient
Utilization Factor
Veiling luminance and glare
vertical illuminance
Very Short distribution
VH diagram
wavelength
wide beam

The answers to the quiz questions in the book are here.

Where to buy "Candelas Lumens and Lux"
$19.99

 

There is now a poster of the book available! Ideal for school, colleges and universities:

Poster of the book

Click here to buy the poster from Zazzle for $16.80.
The poster is 28" by 20" (71 x 51cm)

 
 
 
 

(c) 2014
Contact me if you have any questions about or suggestions for the book.
About the author.