Tuesday, March 17, 2015

Fluorescent vs Daylight

Today, I want to share a piece of information with you about lighting. I painted my Austin painting in my garage with the door open. So the daylight was my light source. However when I view my painting when the garage door was closed, I turned on the fluorescent light on the ceiling. I saw a significant color change. It makes the painting look horrible. To investigate what is going on, I took a photo under the fluorescent illumination and compared it with the photo I took under the daylight. The difference is obvious. Even though the photos are not exactly the same as what I see, but it is rather consistent with my observation.

What is going on? It is not the problem of color temperature because a fluorescent light has about 5000K, which is very similar to that of the daylight. I feel the problem is related to the spectrum of the fluorescent light. The fluorescent light spectrum is not continuous. It has only 4 colored bands leaving many wavelengths in dark. Have you see any galleries using fluorescent light to illuminate their paintings? There must be a reason.


Judy P. said...

I'm glad you brought up this topic Qiang, because the different views of a painting, under various lighting, has always bothered me. Why do we attempt to paint still life under the classic north light, with all the wonderful, subtle blues? I then bring the painting into my sunny dining room, and it is all transformed.
I have asked professional artists about this, and they just say 'well galleries usually have good light'. But how can a collector decide on work in a gallery, when it can look so different in their home? I hope you will have many knowledgable people commenting on this.

Unknown said...

Think this is a very important subject to study. I have noticed when it when I do plein air paintings. The colors are bright, good contrast when I am working on them, after I get home they seem dark and yellowed. I do my painting in the shade outside but still see the contrast.

Unknown said...

Hello Qiang,

You cab have a lot of different lights on fluorescent. I will try to explain, but it could be hard to follow because I am french and some tecnical information could be different.

You have an internationnal number on fluorescent tubes : the first part is for the color temperature, the second one for the IRC (Indice de Rendu des Couleurs in French) : the translation seems to be CRI in English (Color Rendering Index).

This index show the quality of the rendering of colors : the higher the number, the better the exactness. For example CRI 50-70% is for industrial light (low quality), CRI 80-85% for home light (average accuracy) and CRI > 90% is for best accuracy (graphic arts, etc).
You have an international 3 digit number on your light. The fisrt one is for the CRI (rounded to ten) and the 2nd and 3rd for the temperature.

For example 640 is for CR1 60% and a color temperature of 4000 K.

And 827 will be for a CRI 80-85% and a color temperature of 2700 K.

This could help you to choose a better light for your work.

Personnally I use a led video light. You can find some on the web with a color temperature shift.

I hope my "french" explanations could help you.


CBreier said...

What was the white balance setting that you used? Was it auto white balance, fluorescent, daylight etc. also did you check the color temperature on the light to make sure it was 5000K? Fluorescent lights are available in various color temperatures.

Good job on the painting!

Gruhakhoj.com said...

Great information shared here. If you are looking for residential, commercial property for sale (brokerage free) then your search is over now because we gruhkhoj provides best commercial office shops properties at affordable rates. Thanks for sharing. Real Estate Satara