The ideal light source in a traditional atalier is daylight coming from a high north facing window. But this comes with several downsides: not everyone has a north facing window high enough and working at daylight limits you to just a few hours at the easel. If you have a full-day job and can only get to the easel in winter when it is already dark, you are dependent on an artificial light source.
Why coming from high above?
The human brain is still as it was before the invention of artificial light. For a human brain, the sun is the most natural source of light and it recognizes nature best with the natural sunlight. This is the best way to recognize faces.
Form is represented by light and a light source that comes from above like the sun has the most natural effect on our brain.
Everyone knows the problem with flash photography: the face looks like a moon face and you don’t recognize yourself so easily. You are shocked that you seem to have gained 10 pounds.
The reason is quite simple: with the photo flash the light comes directly from the front and there are hardly any shadows. Only strong midtones and highlights show the face. But the shadows are needed to depict the unique structure of a person’s face.
Why northern light?
We all love beautiful sunsets and the reddish colours warm our hearts. But when the sun is low in the evening, all things are influenced by this strong red light and we cannot see the true colour of an object. It is similar in the morning. This is because the sun’s light has such an angle of incidence into the atmosphere that only long-wave light rays hit the earth.
Between morning and evening the light spectrum of the sun is most evenly distributed among the spectral colours and we recognize the colours of objects best.
Warm light has a low light temperature which is measured in Kelvin. An ordinary light bulb with warm light has around 2000-3000 Kelvin. From your own experience, you will know that warm light is not suitable for correctly representing colours. How can one mix the right color in such a light? Any mixed color will have too little yellow-red and look too cool in neutral daylight.
Daylight has a colour temperature of over 4000 Kelvin. When buying such lamps for your studio, pay at least attention to the colour temperature.
Color Rendering Index (CRI)
Now comes the CRI into play. The CRI is the Color Rendering Index and does not describe the temperature, but the characteristic of a lamp to represent the spectrum of daylight as much as possible. When buying a daylight lamp, pay attention to a high CRI. Generally speaking, the higher the CRI, the more expensive the lamp. However, it does not necessarily have to be the most expensive lamp for your atelier. CRI values of over 90 are completely sufficient for your purposes.
In this video you will learn more about how a high CRI can improve color perception.
If you have regular T8 Light Tube fixtures the Hyperikon Daylight LED tubes might be the right thing for you. Please watch the video below to learn more on how they work and what you need to do, to make these work in your fixtures. The guy who made this review mentions flickering which is normal but this only occurs while filming. You do not perceive this with your eyes. This has to do with the camera’s shutter speed and the current frequency of the lamp. Switching from mercury containing light tubes to LED technology is always best.
Hyperikon 4 Foot LED Light, 45 Watt (18W) Clear, T8 Tube Lighting, 4000k Daylight, CRI90 Dual End Powered, UL, DLC, 4 Pack
✔ SAVE 60% INSTANTLY - Save 60% on your electricity bill! Replace 45W fluorescent tubes with 18W LED.
✔ 45,000 HOUR LIFETIME - With an astonishing life rating of 45,000 hours, or 21 years with 6 hrs/day of use, replacing your tubes is now a thing of the past.
✔ CRI90+, BRING OUTDOOR LIGHT INDOORS - Hyperikon’s CRI90+ technology provides near-sunlight quality light for true color rendering and consistency inside your office, warehouse or industrial space. Have sunlight on a cloudy day!
If you don’t have a light tube fixtures but ordinary screwable lamps, the following LED bulbs are just right for you.
Cree LED 100W Equivalent Light Bulb, A21, Dimmable, CRI 90 (Daylight, 3-Pack)
Energy used: 17-Watts (equivalent to a 100-Watt incandescent light bulb)
Estimated yearly energy cost: $2.05 (based on 3-hour/day, 11/kWh)
Light quality: 90+ CRI - for vibrant, rich and natural colors