Findings from a study in New Zealand indicate that it is likely a majority of people are unable to tell the difference between the light of an incandescent light bulb and that of a compact fluorescent light bulb. Energy efficient light bulbs have long had a stigma attached to them regarding light quality, flickering, and other similar issues, but improvements in compact fluorescent technology have done away with those concerns.
As is the case with a lot of things, people who tried early CFLs and did not like the light or perceived flickering, kept their negative notions of energy efficient light bulbs long past the time when their concerns were addressed. New compact fluorescent light bulbs
have no perceptible flicker, and with the right color temperature it's extremely difficult if not impossible to tell the difference between the light of an incandescent and that of the CFL. The variety of color temperatures available also provides a nice selection of light tones that was previously unavailable with incandescent light bulbs.
The study in New Zealand, called the RightLight Challenge, reported findings that a little over two-thirds of participants could not see any difference between incandescent light and compact fluorescent light. The test/study involved about 850 purchasers of both incandescents and CFLs and was conducted on two days in July, the first being the 17th and the second the 24th. Participants viewed two identical booths which were illuminated by either incandescent or compact fluorescent light bulbs, and then were asked if they could tell what kind of light bulb was in each booth.
According to the study, 68% of the people were quite certain they'd be able to tell which booth housed energy efficient light bulbs. Nonetheless, findings show that 68% of people failed to guess correctly as to which light bulb illuminated which booth. This is an improvement both in the CFL bulbs themselves, and in the perception of those who would use them.