The quality of the "white" light might be very different from a low cost panel. When you think of white light for photography, you're assuming the light contains approximately the same energy at most of the visible wavelengths, so all the colours in the scene or person you're photographing will come out accurately. Sunlight, flashes (not LED flashes...) and hot lamps will give you a full spectrum of light. But white LEDs aren't "white". They're blue or ultraviolet plus yellow phosphor. There are very large areas in the spectrum they give off with little energy, so a colour that's in that area might appear darker, or even colour shifted.
There aren't many web pages showing spectral charts of white LEDs. See this page, about 3/4 the way down at "White LEDs"
http://edcfeatures.blogspot.com/2006/12/on...-and-color.html Any colour in the valley or before or after the peak will be muted, any colour near a peak will be brighter than normal.
Try this test: get an XRite or other colour chart from a photo store (don't make one by printing it), and compare photos of it taken in clear sky sunlight, with a flash, with a cool-white compact flourescent, and the LED panel, or whatever other lights you have (try a white LED flashlight, although that's an unfair substitute for a white LED photo light). Use a raw file or jpg with the camera colour style set to the kind of light you're using.
If you have an image editor with a white balance picker, open each one, set the white balance from the white square. Then compare them onscreen. You'll be disillusioned by some lights!
I haven't updated this comparison in a long time but will once some LEDs get cheaper.
http://www.pbase.com/andy_fraser/image/89490008 This whole comparison is "anchored" to white by the top left white square, shot with the Canon flash. RAW files were used for all shots.
Andy
