For the photographer light is important from start to finish – capture, editing, printing, and display. Solux offers products designed to give you the highest quality viewing light at surprisingly affordable rates. How much does high quality viewing light affect the way you see things? Dramatically! Recently, the Musée d’Orsay in Paris France joined the list of SoLux users that include the National Gallery of Art, the Van Gogh Museum, the Rijksmuseum, the Gugenheim and many other museums, galleries and homes. In every case they had to see it to believe it. Once they did, they’ve never looked back (or in any other light). The same thing happened to me; now I only use Solux lighting. See it and you’ll believe it too. (Check out my review and their website for more information.)
Phil Bradfield, PHD, VP-Tailored Lighting Inc. (Solux), provides a number of insightful answers about light and Solux products.
JP    So, there  are three things that are critical in evaluating light. Amount (lux), temperature (Kelvin degrees), and spectral distribution (smooth or spikey).  Solux offers a variety of choices. Help us understand what they are and how to choose between them.
PB    Excellent question JP.  These are very common lighting terms that are important to understand … .
With respect to color perception, the most important aspect of light is the “spectral (power) distribution” (SPD) since it has the most influence on the colors we perceive. The SPD is simply a careful measurement of the amount of each of the different colors (wavelengths) that make up the light in question.   It is typically shown on a graph of Intensity vs wavelength.   The SPD of daylight is relatively smooth and does not have large spikes or gaps in its spectrum.
Color temperature (in degrees Kelvin) is simply a way of quantifying how “warm” or “cool” in appearance a light is.  The higher the Kelvin, the “cooler” the light will appear.  The lower, the “warmer” it will appear. There are a couple of important things to remember about color temperature.
1.  Color temperature has nothing to do with intensity – a higher Kelvin is not necessary “brighter” than a lower Kelvin.   If you have five lights with the same color temperature, it doesn’t change the color temperature, you just have more of that color temperature.
2.  The color temperature tells you nothing at all about its SPD of the light or how well the light renders color.   You need to see the SPD for that.
3.  Just because you have the same color temperature as “daylight” does NOT mean that you have the same spectrum as daylight.   Many lighting companies deliberately mislead customers by stating that their bulb has a color temperature the same as “daylight”  therefore implying (or stating) it is a daylight light.   Do not believe them unless they show you a high resolution SPD of their light as compared with an actual daylight spectrum.  I underline “high resolution” because I know of one lighting company that markets a “full spectrum” light that grossly averages their spectral plot to hide the spikes exhibited by their lights.
The intensity (lux) of light has a secondary influence on color perception after the SPD and as long as the light isn’t very dim or very bright, your color perception is not changed very much.
JP    You use the phrase full-spectrum light. What does that term mean?
PB    What is implied by that phrase is that the bulb in question provides the user with a spectrum of light that simulates daylight. However, the term “full spectrum lighting” is a marketing phrase. There is no official scientific definition for that phrase.  As a result, that phrase is used by many lighting companies to sell lights that do not accurately simulate the spectrum of daylight. SoLux lights provide a very close simulation of the daylight spectrum so I could honestly say that SoLux is a “full-spectrum” light. However, I rarely say that since it might paint SoLux with the same brush as those that misuse that phrase.
JP    What does Solux  offer than others don’t?
PB    SoLux bulbs provide a smooth spectrum (SPD).   As a result SoLux provides superior color rendering.  The resulting visual difference can be quite remarkable.
JP    “Remarkable?”  Can you explain a little more what you mean by that?
PB    I’ll do my best but it is a visual affect that you have to see to really “get.”  Some years ago we did research on finding the “best” light for lighting artwork.   That work led us to make the 3500K SoLux bulbs and its spectrum really makes color in art and photos  “pop.”    There is youtube.com video that does give you some idea of the effect.   http://www.youtube.com/watch?v=CLSxyCgyq3E <http://www.youtube.com/watch?v=CLSxyCgyq3E>
JP    How many types of Solux bulbs are offered?
PB    We offer SoLux in following color temperatures – 3500K, 4100K, 4700K  in both 35 and 50 watt bulbs.   All of those color temperatures and wattages are offered in four different beam spreads (narrow spot, spot, narrow flood and flood).  We also offer a 5000K bulb but it is only available as a 36 degree beamspread and 50 watts.
The 3500K SoLux is primarily a light for color, art, homes and stores when you want to improve their presentation.   The 4100K is popular with diamond stores and is just a tiny bit better than the 3500K SoLux for illuminating black and white photos – it increases contrast.   The 4700K is used by those that want a very accurate simulation of D50 for doing color matching.   One common user of the 4700K are autobody shops for checking paint jobs.   Many photographers use the 4700K for color proofing/color management although some use the 3500K SoLux for that since that is the light source they will use for displaying the (color) photo on the wall.
The SPD of all SoLux bulbs is smooth and has no spikes or large gaps.  The 3500K and 4100K SoLux bulbs have ultra-low UV and greatly reduced IR output and are therefore very art-friendly.
JP    What accessories are offered?
PB    In addition to the SoLux bulbs we offer track lighting, recessed lighting, desk and floor task lamps as well as lights for closets and 10 bulb arrays to light up large areas.
JP
Any plans for the future you’d like to reveal now?
PB    We are working on screw-in PAR bulbs and are making progress on that front. Only the 3500K and 3250K will be available at first.   Later, we want to offer 4100K PARs.     I know that you are wanting to know “WHEN?”   but every time I have said “We will have them later this year.” I have been proven wrong.    I will say that as soon as they are available, we will notify you so that you can, (ahem), illuminate your readers as to their availability.
I frequently get asked about LEDs.  LEDs do show some promise but their spectrum still isn’t right and it is something we are working on.   Don’t get me wrong.   There some applications where LEDs are awesome.  For example, tail lights in cars, stop and go lights, EXIT signs, emergency lighting and anywhere you don’t care about how it makes something look.   But when you are trying to makes something look likes it is worth what you paid for it – art, your home, etc. then don’t settle for poor lighting.
One guy who was using LEDs to light some art said to me “My LEDs are rated for 100,000 hours which is basically forever.”  My response was, “True, but you have bad looking art for the rest of your life.”
It is kind of like that old saying:  Buy quality – cry once.  Buy low quality – cry all the time.
JP    You love light and optics as much or more than I do. Tell me what fuels your passion for light?
PB    I am fortunate to have a job that I still get a “kick” out of.   The kick I get is seeing the reaction to our lights from someone who sees it for the first time or who calls me after they have received our lights to say that they “LOVE!” our lights.   In today’s world it is fun to surprise people with something so simple that makes such a big difference.
Check out Solux products here.
See them in action in my workshops here.