Science light!

This is a shot of my easel showing the rack I have sticking out from its mast. Here is where I hang my lighting. When I built the studio I installed an outlet at nearly ceiling level, which is switched from beside my easel. I put in the outlet and the rack rather than a fixed set of lights because I wanted to be able to experiment and change my lighting from time to time. Usually I work only by natural light from my large north windows. However this time of year when the days are so short or when I am in vampire mode and staying up all night, I need to have science light!

There have been a lot of different combinations of fixtures hung from that sad, embarrassing flap above my easel! For a while I liked the idea of using the same kind of halogen track lighting that my galleries had. But I was unhappy with the way my color looked the next morning when I saw what I had done in the cool remorseless light of day.

When I have tried to paint under incandescent light or ordinary florescent tubes my color is way off too. Usually the pictures look dull or lean too far towards one color cast or another. I have never really worked too hard at achieving studio lighting for night painting, and I am too cheap to invest in fancy lighting for that. But last week I decided that I needed to get better light, as I have been working in my studio a lot at night lately.

With all of the people who read my writing I am sure that someone is a lighting engineer, and I know one guy on the Cape ( who often serves as the volunteer scientific adviser to this blog) who is a physicist or something. They all know lots more than I do and will probably weigh in on the scientific side here but I will summarize briefly what I know,with no equations. The people who deal with this for a living throw around formulas and equations that make my head hurt. I'm a high school drop out, I am hiding from mathematics.

• daylight is about 5500 Kelvin ( a measurement of color temperature) That actually varies as the light from a north window is quite cool and morning light would be much warmer.
  
• Most commonly available florescent tubes and also incandescent bulbs are far warmer than that .
• Any bulb or tube can be labeled "daylight" and not be suitable for painting.
  
• CRI ( color rendering index) is a measurement of how well one can judge color under a particular light. This is a real important number when buying your lights.
• So when you shop for studio lighting you are going to have to go florescent and look for a temp of about 5500 Kelvin or somewhere near that. BUT very importantly, you will need to find bulbs that have a CRI of 90 or above.
• Ordinary household florescents have a CRI as low as 70. That's why you look like a corpse under them. It's the lights, you don't really look that bad.
  
• There are expensive "full spectrum bulbs that can be found online that will meet this test and claim to cure you of the "winter blues", (seasonal affective disorder) if you have that go see a doctor or an herbalist. These lights are no doubt very fine, but I am too cheap to buy them. They are called "full spectrum" bulbs because they produce all of the different colors of light needed to judge your color.

Home Depot ( or your local big box retailer) sells lots of different fluorescent tubes. Most of those are far from being acceptable in the studio. But a few are. I just picked up a couple of sets made by Philips that seem to work fine. A purist or a scientist might tell me that the expensive bulbs sold by Tubes R' US might be better, and perhaps they are, I don't know because as I mentioned before, I am too cheap to find out.

Since I last bought tubes the bulbs have wizened down to a thinner size so I picked up a set of those and a shop light nest to house them. They seem to be noticeably brighter than new tubes in the old style dimension. I now have four florescent tubes about three feet over my head as I work. The new style bulbs are 22 watts and the old style are 40 watts.

Either way, they seem to be fine so far and I can work under them at night and my paintings don't look radically different by daylight. Four bulbs and a two light fixture ( I had one fixture already in inventory) cost me under fifty bucks. That leaves me with money to spend on cigars and Moxie, and maybe I will have a candy lunch!