. . in the "unreal world" of product photography where you can have any lighting you want :-)
I'm in the habit of using LED lamps, an overhead fluorescent and a MiniMag (for highlights) - all at the same time (gasp!). Now, I'm the proud owner of a Sigma Flash thingy which fits nicely on top of the SD10. Yet another color temperature beaming down on my subjects. So, I set up this rig to see if that could work.
The backside of a gray card at left to reflect any stray flash. The flash aimed at the wall and some tracing paper at right for a bit of flash diffusion. Do not laugh at my studio . . . nor at my hand-held picture quality, we're not testing for acutance today.
The plan was to take shots under several kinds of lighting and then one with them all. In PhotoShop, to do the white balance and then compare the Red, Green and Blue color hues of each shot and also to list the theoretical (D65) hues of the Card (don't leave home without it).
So . . .
Overhead lamp:
LED:
Flash:
All together:
The rather unsurprising results, in degrees of hue according to Adobe PSE6:
Lamp, Red, Green, Blue
tube, 17, 100, 217
LED, 21, 99, 238
flash, 344, 99, 220
all, 345, 97, 224
card, 357, 111, 237 (theoretical under D65 lighting).
From which we learn that colors don't look too bad under varied lighting but we also learn that white balancing is no fix for imperfect lamp spectral emissions. Witness the brown red under LED lighting as opposed to a much redder red with the flash, and so on and so forth . . .
And, for my purposes, a bit of a flash is a very good thing!