My problem with Compact Fluorescent Lamps

[Liron]

I have a problem with compact fluorescent lamps that's not the usual
problem.

I keep reading all the publicity that says that the light from warm white
(2700K) compact fluorescent lamps has the same great warm yellow colour as
incandescent bulbs, but to me, the light from most of these lamps
(especially ones I've bought recently) does not look anything like that.

To me, the colour looks more orangy, sometimes brown, or with a pink or
purple tinge, with each brand of lamp having a slightly different colour
from the other. In some cases, two lamps of the same make and/or model will
have different coloured light too.

The reason is that I don't have any lenses in my eyes. They were removed
when I was young as I was born with cataracts. As a result, I can see some
ultraviolet light, thus the light from compact fluorescent bulbs looks
different to me.

However, if I look at the same bulbs through lenses which block out 100% of
the light, they do give off a similar enough yellow colour to incandescent
bulbs. Not exactly the same, but the difference doesn't matter. But if I
use normal glasses (which don't block out all of the UV light) they don't
look like that.

I don't have this problem with cool white or daylight bulbs. They do look a
little different, but not that different. It's just the warm white compact
fluorescent bulbs that are giving me this problem.

Any comments?

Liron

 

[Don Klipstein]

I have a problem with compact fluorescent lamps that's not the usual
problem.

I keep reading all the publicity that says that the light from warm white
(2700K) compact fluorescent lamps has the same great warm yellow colour as
incandescent bulbs, but to me, the light from most of these lamps
(especially ones I've bought recently) does not look anything like that.

To me, the colour looks more orangy, sometimes brown, or with a pink or
purple tinge, with each brand of lamp having a slightly different colour
from the other. In some cases, two lamps of the same make and/or model will
have different coloured light too.

The reason is that I don't have any lenses in my eyes. They were removed
when I was young as I was born with cataracts. As a result, I can see some
ultraviolet light, thus the light from compact fluorescent bulbs looks
different to me.

However, if I look at the same bulbs through lenses which block out 100% of
the light, they do give off a similar enough yellow colour to incandescent
bulbs. Not exactly the same, but the difference doesn't matter. But if I
use normal glasses (which don't block out all of the UV light) they don't
look like that.

I don't have this problem with cool white or daylight bulbs. They do look a
little different, but not that different. It's just the warm white compact
fluorescent bulbs that are giving me this problem.

Any comments?

Have you determined whether you are seeing the 365-366 nm UV cluster, or
seeing the 404.7 nm line more than "normal", or both?

Eyeglasses are available with polycarbonate lenses, and those block the
365-366 nm cluster. Eyeglasses can also be coated with a "UV coating"
that blocks 365-366 nm and also does a slight bit of attenuation of 404.7
nm.

Polycarbonate sheet, although different from the polycarbonate used for
eyeglass lenses, also blocks the 365-366 nm cluster. UV-block stage
lighting filter (such as GAM 1510 or equivalent) gel blocks the 365-366 nm
cluster and attenuates 404.7 nm a little. A few of your light fixtures
may accomodate this.

Higher color temperature CFLs (and other higher color temperature
triphosphors) have a blue-emitting phosphor that actually utilizes a fair
amount of the 365-366 and a little of the 404.7. Most other fluorescent
lamp phosphors do not absorb these wavelengths.

- Don Klipstein ([email protected])

 

[Andrew Gabriel]

Regardless of whether CFLs do or do not emit long wave UV (I think the amount is
negligible anyway), people with cataract surgery usually perceive the colors of
lamps with Hg burners differently.

My mother has had cataract surgery last year only in the one eye and since then
I've pestered her with questions about the color hue of various lamps, including
a blended light lamp and the kitchen CFLs.

The kitchen CFLs (which are all 2700K OSRAM Dulux), she perceives as bright
yellow with the new lens, and dull brown/beige with her own lens.

The blended light lamp mext to my desk she perceives as cabbage-green with the
old lens, and bluish-white with the new lens.

People often perceive colour slightly differently in each eye anyway
(without having had any cataract surgery).

 

[[email protected]]

| In article <1220804542.730765@athprx03>,
|>
|> Regardless of whether CFLs do or do not emit long wave UV (I think the amount is
|> negligible anyway), people with cataract surgery usually perceive the colors of
|> lamps with Hg burners differently.
|>
|> My mother has had cataract surgery last year only in the one eye and since then
|> I've pestered her with questions about the color hue of various lamps, including
|> a blended light lamp and the kitchen CFLs.
|>
|> The kitchen CFLs (which are all 2700K OSRAM Dulux), she perceives as bright
|> yellow with the new lens, and dull brown/beige with her own lens.
|>
|> The blended light lamp mext to my desk she perceives as cabbage-green with the
|> old lens, and bluish-white with the new lens.
|
| People often perceive colour slightly differently in each eye anyway
| (without having had any cataract surgery).

And perception of color can vary even more so between people. About the only
way to get a uniform acceptance of color is to make sure the emission is a
uniform continuous spectrum. That's harder to do with fluorescent and LED.
My own goal with lighting is to get a uniform edge focus. Incandescent does
this adequately, balancing this with a familiary "white" color. Fluorescent
and LED do this poorly due to the light in 2 or 3 distinct strong narrow bands.
A single color, or one with blue/violet far away, such as sodium, is actually
as good or better for uniform edge focus. It just has a lousy color. There
is no perfect light. But fluorescent and LED are worse.