GE sunshine 5000K CFL

UnknownVT

Flashlight Enthusiast
Joined
Dec 27, 2002
Messages
3,671
Saw in my local supermarket (Kroger) GE Sunshine 5000K CFL -

GEsunshine500KCFL13watt.jpg


I can't seem to find it on the GE site - but it appears to be quite easily available once I did a search on the web -
the 13-watt part # GE 71763.

I have a couple of GE 6500K 15-watt CFLs that I use to examine colors under "daylight" - but find those still a bit on the cool side -
these 5000K sunshine CFLs would seem to be ideal for my usage.

Anyone tried these yet?
 

Lightdoctor

Enlightened
Joined
Feb 21, 2010
Messages
389
Have not used this specific brand but can say that 5000K lamps is as far as you want to go in the blue direction on the Kelvin scale and still have usable light. These make a good all around ambient light. (I think that 4100K with 80% + CRI is better for color rendering.)
 

blasterman

Flashlight Enthusiast
Joined
Jul 17, 2008
Messages
1,802
They all use the same phosphors, so it doesn't make much difference.

If you want 'neutral' looking CFLs you have to find some 4100k. The only decent looking CLFs above 4100k are enhanced CRI bulbs that are a specialty item.
 

UnknownVT

Flashlight Enthusiast
Joined
Dec 27, 2002
Messages
3,671
If you want 'neutral' looking CFLs you have to find some 4100k.

If it's of any interest I looked more carefully today, and noticed in the same supermarket some GE 4100K spiral CFLs - they called it Energy Smart Instant On "cool white" and it was only marked as 4100K at the bottom left corner on the front - it was only because I wanted to know the color temperature that I saw the 4100K - otherwise I would have easily missed it. I cannot find any images on the web for this, and it does not seem to be on the GE lighting web site either, yet.

But it seems both 5000K and and 4100K are now available from GE -
which means they really are now in the mainstream.
 

jtr1962

Flashaholic
Joined
Nov 22, 2003
Messages
7,506
Location
Flushing, NY
But it seems both 5000K and and 4100K are now available from GE -
which means they really are now in the mainstream.
I noticed that just looking inside windows when I go walks at night. More and more people are using 4100K or 5000K. Evidently now that they realize CFLs don't HAVE to imitate incandescent, they're choosing the tint which they prefer. I find it interesting also that the daylights are almost always sold out in Home Depot, while they are tons of warm whites sitting on the shelves. The great thing though is we finally have choice! It used to be a major ordeal to try and find CFLs in anything but 2700K or 3000K.
 

blasterman

Flashlight Enthusiast
Joined
Jul 17, 2008
Messages
1,802
I'm seeing more varities of CFLs in big box stores, other than your typical choice of fake incan or 6000k 'Full Spectrum / Natural spectrum / what ever spectrum'. Only thing the high spectrum bulbs are good for is plants. :D

3500k-4100k has been the dominant color in corporate T8s for a long time, so I've never quite figured out why consumer CFLs have typically been limited to CFLs flavors of either fake incan, or county morgue. I'm glad to see 4100k finally hit the big box stores because they are nice looking bulbs. Also, I'm astounded at the number of people I run into that are running generic 6000k bulbs, hate them, but feel they have to. Or, their spouse insists they use them. 5000k / high CRI is pretty nice to work under, but you aren't going to find them for cheap.
 

UnknownVT

Flashlight Enthusiast
Joined
Dec 27, 2002
Messages
3,671
I noticed that just looking inside windows when I go walks at night. More and more people are using 4100K or 5000K. Evidently now that they realize CFLs don't HAVE to imitate incandescent, they're choosing the tint which they prefer. I find it interesting also that the daylights are almost always sold out in Home Depot, while they are tons of warm whites sitting on the shelves. The great thing though is we finally have choice! It used to be a major ordeal to try and find CFLs in anything but 2700K or 3000K.

Ha-ha! I'm one of those people who still thinks about 2700K is comfortable - not certain if it's conditioning or physiology.
However I do keep my house at lower light levels mostly 10 and 13 watt CFLs (40 and 60 watt equiv).

If one looks at the Kruithof curve the bandwidth of CCT that seems like white to our eyes becomes pretty narrow for lower light levels - the graph shown at Wikipedia actually highlights the 2700K point and one can see there is very little wriggle room for what most people would consider "white" light.

Of course with higher light levels all this changes and may require higher CCTs. Again I do realize this is generalization and may not apply to everyone - but my own reactions seem to fall into the "masses".

My interest in "Daylight" 6500K and "Sunlight" 5000K are not for general household illumination (as I am quite happy with dim 2700K) - but for an inspection lamp of sorts to examine colors under simulated "daylight" - eg: looking at photos so I don't miss shadings in blues or yellows. The cheapo 6500K "Daylight" GE CFL seems to be satisfactory at 13 watts - but I have the feeling that it's slightly cool-blue'ish - not really enough cause to complain/abandon - but that's the reason why I was interested in the "Sunlight" 5000K - hoping it'd do as well as the 6500K without the cool-blue feeling.

Interesting article:

The Color of White

paper published by the WAAC - Western Association for Art Conservation -
specifically on illumination for displaying art/paintings -
their findings fit well in the Kruithof curve -

" The fact that most observers chose the same preferred color temperature within a narrow range is further evidence that the choice of color temperature involves more than an arbitrary aesthetic preference. It is based on a fundamental property of human vision. To further understand the preference for a specific color temperature, additional studies were undertaken in a non-art context. A white reflective surface was illuminated at a fixed intensity as the color temperature was increased and decreased in small increments between 3000° K and 4700° K. Observers were asked to describe the light as warm, cool or intermediate. For a surface illuminated at 20 foot candles, a value around 3700° K was chosen as the intermediate value, measured with a Minolta photographic color temperature meter (Model II). At 20 foot candles, 3700° K appears as an achromatic white light compared to higher or lower color temperature sources. Coincidentally, the choice of 3700° K was the preferred color temperature chosen on aesthetic grounds when looking at paintings. This suggests that the aesthetic preference for a specific color temperature derives from a fundamental characteristic of human color perception."

3700K was the optimal CCT for displaying art - but note that is at 20 foot candles - which is pretty high for household ambient lighting - this level may be reached or exceeded under a reading lamp - but most households are not lit that high overall -

Offices however do have to have higher ambient lighting -
OSHA's recommendation:

"Generally, for paper tasks and offices with CRT displays, office lighting should range between 20 to 50 foot-candles. If LCD monitors are in use, higher levels of light are usually needed for the same viewing tasks (up to 73 foot-candles)."

Remember these are at the work surface -
but that's why higher color temperatures in offices would seem appropriate

20 foot-candles = ~215 Lux - checking on the larger version of the Kruithof curve
one can see why 3700K makes sense for the WAAC art illumination.

Whereas office lighting of say up to 50 foot-candles = ~538 Lux - a more appropriate color temperature would seem like about 4100K - and since the Kruithof curve "envelope" is much wider at that point 4100K would seem optimal for both CRT environments as well as LCD usage which OSHA recommends up to 73 foot-candles = ~786 Lux Max
 
Last edited:

blasterman

Flashlight Enthusiast
Joined
Jul 17, 2008
Messages
1,802
that's the reason why I was interested in the "Sunlight" 5000K - hoping it'd do as well as the 6500K without the cool-blue feeling.

The problem with cheap, 'daylight' CFLs is their phosphor range is very 'spikey', and they tend to have very weak red response. We complain about white LEDs not going beyond organge-red, but fluorescent can be even more anemic. Typical CFL phosphor mixes are just the minimum required to reach an adequate color value.

I'm not saying the 'Sunlight 5000k' is no better than a cheap Feit brand bulb, but I see no reason why it would be better. High CRI, +5000k CFLs are simply more expensive to make, and I've yet to see one in a conventional retail store. Art stores often have them, and they are readily obtainable online for $10. If the bulb in question is using a higher CRI phosphor mix, it would probably broadcast it on the bix in big letters :huh:
 

UnknownVT

Flashlight Enthusiast
Joined
Dec 27, 2002
Messages
3,671
The problem with cheap, 'daylight' CFLs is their phosphor range is very 'spikey', and they tend to have very weak red response.

Thanks for that -
that probably explains why I feel (rather than see) the cheapo 6500K GE CFL is a bit cool-blue'ish.

The 5000K "Sunlight" version may not be all that much better than the 6500K - but hey! it's cheap and I'm cheap :eek: -
but it is better than the 2700K CFL I have in in my house for what I want to do - I merely want to "see" under simulated "daylight" -
and will do my more critical examination under real daylight.
 

blasterman

Flashlight Enthusiast
Joined
Jul 17, 2008
Messages
1,802
Yup, let you eyes do the talking. Still, if you really like the initial color of 5000k but not the abrupt nature of the their spectrum, it might be worth it to get a couple of the true high CRI 5000k bulbs just to see how you like them.

Cool white LEDs might be bland, but unlike cheap CFLs, at least the spectrum is fairy smooth.
 

UnknownVT

Flashlight Enthusiast
Joined
Dec 27, 2002
Messages
3,671
Cool white LEDs might be bland, but unlike cheap CFLs, at least the spectrum is fairy smooth.

Don't cool white LEDs have relatively low CRI?
isn't this due to peaks and discontinuous spectrum?

For example LumiLEDs claim that their Luxeon has then highest CRI white LEDs - however their specs for the Luxeon Rebel cool white 6500K has a typical CRI = 70 (same for the Luxeon III and K2).

Whereas an average GE CFL both 2700K and 6500K seem to claim CRI=82.
 

UnknownVT

Flashlight Enthusiast
Joined
Dec 27, 2002
Messages
3,671
Saw in my local supermarket (Kroger) GE Sunshine 5000K CFL

The GE range of CFLs were on sale at Krogers this week, so I took the plunge and bought a GE 13 watt 5000K Sunshine CFL ($4.79).

First turn on was a bit worrying - the CFL did come on "instantly" - BUT it came on at about 1/2 power/brightness with the top 1/3 or so of the spiral being noticeably darker - and I thought the bulb was faulty - but it gradually started to become brighter.

I left the CFL on for at least 15 minutes and it did attain what seems like full brightness.

Now whenever I turn the light on - it still does come on "instantly" but now with at least good acceptable initial brightness - and reaches what seems like full brightness fairly quickly - well, at least it is comparable to the 13watt/2700K and 15watt/6500K GE CFLs I have.

Now the very good news - at least for me -
this is just about everything I'd hoped for in a cheapo inspection light -
it is bright day-sun-light like and does not have that blue-ish tint that the 6500K "Daylight" version has - this is especially noticeable in any peripheral spill - ie: in the areas not in the main direct light area.

For the peripheral spill the 6500K seems blue and not very pleasant (not quite as bad a "morgue white", though) - whereas this Sunshine 5000K - seems pretty pleasant - and just glancing at the illuminated area - does look like sunlight.

I do realize that the CRI is not high, probably around the average consumer grade of CRI=82. BUT I was very pleasantly surprised by how good the light is, and for me just the ticket to examine things under "simulated" sun/daylight.

Although the 6500K daylight version was acceptable -
this Sunlight 5000K is just a lot better - for me.

Note: I am only using this 5000K for a cheapo inspection light - and not for my general household lighting -
I still like the 2700K Soft White CFL - as my general level of home lighting is pretty low -
eg: my living room is lit by a single 10watt (40watt equiv) 2700K CFL most of the time.
For reading I turn on another 10watt 2700K CFL that's about 4ft from the reading surface.
 
Last edited:

maxspeeds

Flashlight Enthusiast
Joined
Jan 24, 2007
Messages
2,177
Location
Oahu, Hawaii
In continuation of my pursuit in CCT and CRI with flashlights, I have recently upgraded my 4' T12 fluorescent lamps to Sylvania Sunstick line of lamps. They are 5000K with 90CRI. I found them at my local Lowes. I chose these because they had the highest color rendition. They are amazingly pure white and have superior color rendering. I find them a bit harsher on my eyes than 4100K, but they are great for reading and keeping me awake while studying. :D
 

blasterman

Flashlight Enthusiast
Joined
Jul 17, 2008
Messages
1,802
I just finished some contract work for a company that had the entire corporate floors using 5000k / ~90CRI lamps. While I prefer 4100k, the color keeps people attentive and it's much superior to typical big bix store 'natural sunlight' CFLs. You should see the potted plants on top of their cubes growing like crazy :D

The GE bulb sounds like a step in the right direction. Still, I don't get why 4100k isn't more popular in CFL.
 

UnknownVT

Flashlight Enthusiast
Joined
Dec 27, 2002
Messages
3,671
FWIW - I took a pic with Fixed Daylight White Balance of a Macbeth chart illuminated by this single 13watt GE 5000K Sunshine CFL low ceiling mount about 58" away.

Here's a matrix of comparison:
GE5000kCFL_DayBal.jpg
Macb_DayLCtrl090929_70.jpg

GE6500KCFL15w_DayWB.jpg
GE6500K2700KdayBb.jpg


This GE 5000K Sunshine CFL seems to do quite well - I realize the differences that a Macbeth shows is very little - but if we look at the bottom row of gray patches the second two from the left are the most telling - the 6500K Daylight CFL betrays the blue-ish tint I see - whereas the 5000K Sunshine does not have that problem.

Compared to real daylight the 5000K CFL may still lack some warmth - as shown in the flesh pink (top row second from left) and the orange (second row first left) patches.

But it's not bad at all to my eyes.
 
Last edited:

Bright+

Newly Enlightened
Joined
Dec 5, 2008
Messages
170
I love it. Until now, short of special ordering, the only way to enjoy 5,000K lighting was getting Chroma 50 or four footer SPX50.

I believe it is the same phosphor as the SPX50.

The SPX50 GE uses on their T8 is not the same as Chroma 50(not available in T8)

Chroma 50 is what is actually used for light box and uses a continuous spectrum phosphor. The SPX50 is an "RGB" phosphor, changing the ratio to alter the color temperature.

Taking a picture is usually useless, because even if you use fixed white balance, the CCD will see two lamps that look very similar to our eyes very differently.

If you use auto white balance, the camera will adjust the gain for each of the color automatically until it is balanced.
 

blasterman

Flashlight Enthusiast
Joined
Jul 17, 2008
Messages
1,802
Chroma 50 is what is actually used for light box and uses a continuous spectrum phosphor.

Uh, no. That is, unless you are buying a really cheap light box. For critical color matching you need MacBeth tubes, or anything 95 CRI or higher. The Chroma50 is a nice phosphor mix aethestically, but it's only CRI 90 or so - rather generic. A good choice for the office, or work areas. Not something you want in a light box unless you aren't that critical.

'Continuous spectrum phosphor' is an oxymoron - sorry. There is no such thing. High CRI fluorescent tubes fill in the gaps as best they can with less efficient spectral bands, then rely on the rather out-dated CRI spec to inflate their numbers ;)

Not sure what phosphor mix is in the sunshine 5000. Be nice if it were the Chroma 50 mix, but intuition tells me it would be the cheaper one.

The reason I don't like MacBeth charts is they are a low gamut target, and often perceptual differences between bulbs doesn't as great as it does with your eyeballs. The RGB sensor in your digital camera also misses some colors, but MacBeth charts just aren't a good reference target for perceptual comparisons.
 

UnknownVT

Flashlight Enthusiast
Joined
Dec 27, 2002
Messages
3,671
The reason I don't like MacBeth charts is they are a low gamut target, and often perceptual differences between bulbs doesn't as great as it does with your eyeballs. The RGB sensor in your digital camera also misses some colors, but MacBeth charts just aren't a good reference target for perceptual comparisons.

I'd agree - there is very little difference on first glance between my photos of the CFL bulbs compared to real daylight - and I'm not too sure if I am seeing the slight/subtle differences or really using my perceptive observation - then looking for the evidence on the photo.

Unfortunately the Macbeth chart is the industry standard used for testing color accuracy for cameras/films - I realize most of the reviews for digital cameras are using software to analyze the test shots - and I have never read any explanation of how to see this difference in accuracy.

The Macbeth chart is also the one the CIE is proposing to use for measurement of CRI especially for LEDs.

There is a paper (expensive) on the CIE proposal for measuring CRI in
CIE TC 1-62

on looking for CIE TC 1-62 I also came across these:

Labsphere
" What is the TC 1-62 Colour Rendering of White LEDs?

The present color rendering system gives a poor rating for white LEDs yet the color appearance of white LEDs is better than color rendering index would suggest. This is a potential barrier to introduction of white LEDs into main stream applications so TC 1-62 was established to investigate, by visual experiments, color rendering properties of white LED light sources and to test the applicability of the CIE color rendering index to white LEDs.
"

Then -
pdf VISUAL OBSERVATION OF COLOUR RENDERING
from Colour and Multimedia Laboratory of the University of Veszprém, Hungary
- where they followed the CIE TC 1-62 recommendation and used the Macbeth chart for the experiment
the visual experiments look very interesting -
their comments on the 4000K tests

" As can be seen, there are huge differences in ordering the lamps according to visual or calculated colour difference. The exceptionally good visual performance of the traditional Cool White lamp is hard to understand, one reason might be that most of the test samples contained only very little long wave radiation. It is also of interest that the small peak wavelength difference between the two clusters produced a large difference in Ra. The rank order for the 6500 K series is the same for all four methods of evaluation. "

I am not too sure if they have taken into account the human eye/brain behavior with different light levels -
as shown in the Kruithof curve -
could this have any bearing on their 4000K results?

EDIT to ADD -

I have found a copy of the CIE TC 1-62 paper that is currently viewable on line using embedded FlashPlayer:

CIE 177 2007 - CIE TC 1-62 paper

haven't found a way to save a copy yet......
 
Last edited:

Bright+

Newly Enlightened
Joined
Dec 5, 2008
Messages
170
Uh, no. That is, unless you are buying a really cheap light box. For critical color matching you need MacBeth tubes, or anything 95 CRI or higher.

What's a "Macbeth tube"? Can you post the specs and SPD?

The usefulness of CRI is debated. The Ra8 system only concerns how well it renders standard eight colors. Of course, it only applies to things viewed directly by eyes and CRI is completely irrelevant to sensors and films.


The CIE has a method for calculating CRI based on data gathered from spectrophotometer, only so that it gives something objective.

If its just about spec numbers, the Philips 950 lamps are rated CRI 98


The Chroma50 is a nice phosphor mix aethestically, but it's only CRI 90 or so - rather generic. A good choice for the office, or work areas. Not something you want in a light box unless you aren't that critical.
Not a good choice for office. Continuous spectrum lamps have broad emission spectrum including ranges our eyes are not very sensitive to, so they're not very efficient. They're sold for color matching and such purpose.

'Continuous spectrum phosphor' is an oxymoron - sorry. There is no such thing. High CRI fluorescent tubes fill in the gaps as best they can with less efficient spectral bands, then rely on the rather out-dated CRI spec to inflate their numbers ;)
Yes there is. Continuous spectrum lamps emit some light over the entire visible spectrum while tri-phosphor lamps use R,G,B phosphors to create desired color.

The difference between cont. and multi-phosphor lamps is that multi-phosphor lamp is designed to focus their output to primary colors and not produce spectrum in between in order to increase efficacy.

The Design 50/Chroma 50 type is only 52 lumens per watt, while the 850 type can get 94 lumens per watt.

Not sure what phosphor mix is in the sunshine 5000. Be nice if it were the Chroma 50 mix, but intuition tells me it would be the cheaper one.
The 40W T12 Sunshine is Chroma 50 and it is marked CRI 90. CFLs and 32W T8 sold as Sunshine are SPX50(GE naming for 850). The Sunshine CFL is Energy Star rated. If it was to be made using Chroma 50 phosphor, it will not meet the efficiency requirement to get the stamp.

I think the Ott Lite CFLs are based on continuous spectrum phosphor.


This is the spectral chart of Sylvania Design 50, a continous spectrum, or "full spectrum" lamp. The peaks are not added. They're natural emission lines from mercury/argon discharge. A clear fluorescent lamp would glow pale blue due to these lines.
9id6jc.jpg


This is an 850 5000K phosphor with 85 CRI. Rather than spectrum being continuous, there are peaks additional to natural mercury/argon peaks. They're added by using phosphors that emit specific peaks. They usually use R, G, and B phosphors, hence tri-phosphor.


auv5lw.jpg


This is the 5000K CRI 98 Philips 950
296hmjc.jpg
 
Last edited:
Top