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pjs2
21st of September 2009 (Mon), 22:30
I have two types of light bulbs in my house fluorescent and those power saving things. My question: Is there a bulb that I can use in standard light fittings that is more forgiving to digital photography?

Digger
21st of September 2009 (Mon), 22:33
those compact fluorescent come in different color temperatures. you can do a custom color temp to match them.

Curtis N
21st of September 2009 (Mon), 23:00
Fluorescent lamps suck.
Either the long skinny ones or the little spiral ones that screw in.
They come in different colors. They all suck.

Sure, you can do a custom WB to "match" almost anything. But that will just make gray look gray. Fluorescent lamps don't render color correctly.

Old-fashioned tungsten (incandescent) bulbs, with the right white balance, will render much better color.

Benji
22nd of September 2009 (Tue), 09:10
Fluorescent lamps suck.
Either the long skinny ones or the little spiral ones that screw in.
They come in different colors. They all suck.

Sure, you can do a custom WB to "match" almost anything. But that will just make gray look gray. Fluorescent lamps don't render color correctly.

Old-fashioned tungsten (incandescent) bulbs, with the right white balance, will render much better color.

Curtis is right. Most flourescent bulbs lack red in their spectrum so even when they are color balanced to an 18% gray card they still emit too much green.

I remember years ago a photographer buddy of mine drilled holes in the center panel of his 4 foot flourescent fixture and added three fixtures that allowed him to screw in three tungsten light bulbs which effectively added the needed red to the flourescent bulbs. I think they were 100 watt. I'm not sure which flourescent bulbs he used as there are at least seven different bulbs cool, neutral, warm, daylight, germicidal, high output white and bright white. Another thing I remember he had to use a slow shutter speed because the flourescent bulbs actually flicker rather than glow like tungsten bulbs do so unless you use a slow shutter speed, they will not record the image properly.

Benji

Curtis N
22nd of September 2009 (Tue), 09:47
the flourescent bulbs actually flicker rather than glow like tungsten bulbs do so unless you use a slow shutter speed, they will not record the image properly.Traditional fluorescent lamps flicker with each cycle of the alternating current used to power them. In the western hemisphere, that's 60 cycles per second. The lamps will flash twice each cycle, or 120 times per second. Both the power and the color temperature of the light are constantly changing.

Any shutter speed faster than 1/125 will result in variations in exposure and color temp. 1/125 will usually render decent consistency, and 1/60 or slower will mitigate the problem entirely.

The newer compact fluorescent (CFL) lamps use electronic ballasts that cycle the power at something like 25,000 hz, and do not exhibit this problem. You can use any shutter speed with these.

Wilt
22nd of September 2009 (Tue), 11:01
while I fundamentally agree with Curtis about the gaps in the color spectrum emitted by CFL, I thought I'd share the results of correcting CFL

Corrected ordinary CFL...
http://i69.photobucket.com/albums/i63/wiltonw/IMG_1164-2-2.jpg

Daylight 'control' sample...
http://i69.photobucket.com/albums/i63/wiltonw/IMG_1921_2.jpg

Corrected 'daylight spectrum CFL'...
http://i69.photobucket.com/albums/i63/wiltonw/IMG_1165-2.jpg