# Can you tell the difference between 70 and 80 CRI? 80 to 90 CRI?



## ledmitter_nli

By casual observation is there a big difference?

Edit: (woops meant to post in the LED forum)


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## AnAppleSnail

If all the other light characteristics are the same, not usually. It depends on the SPD of the light and which colors you are viewing by it. I find that tint and CCT are far more noticeable (And glaring, when inappropriate).


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## N8N

yeah, I'm not really sure if I can tell the difference between low and high CRI sources or if I see other things that I find objectionable in the low CRI sources, as I really don't have any to compare back to back that are the same CCT. I've definitely seen sources that I didn't *like* that were low CRI but those also tend to have the habit of being stupid high CCTs.

I can say that I can discern the difference between a typical CFL and an incandescent and/or an L-prize bulb at about the same CCT, but the CRI of a typical CFL is so abysmal that that isn't really surprising.


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## ledmitter_nli

I was really scrutinizing CREE's emitter labeling and starting to figure out all the nuances.

Not only are there actual tint labels to contend with, but tints have their own CRI order codes. Like the 5C1 bin which I've learned has a CRI variation from 70 Typical, 75 Typical and 80 Minimum.

Cutter is evidently using 70 Typical for my quad R4-5C1 --> XPGBWT-01-0000-00GE5 <-- where B = XP-G2 | 01 = 70 CRI Typical Out Door White.

Damn. Almost as perfect as it could have been.  There is an 80 CRI Minimum but you take a Flux hit going from [R4] 130 Flux @ 350mA to [R2] 114 Flux @ 350mA. Or about 12% (192 less lumens) in my quad translated.

So a difference of 10 CRI that would be barely perceptible in the first place isn't really worth it.


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## TEEJ

ledmitter_nli said:


> I was really scrutinizing CREE's emitter labeling and starting to figure out all the nuances.
> 
> Not only are there actual tint labels to contend with, but tints have their own CRI order codes. Like the the 5C bin which I've learned has a CRI variation from 70 Typical, 80 Typical and 90 Minimum.
> 
> Cutter is evidently using 70 Typical for my R4-5C1 --> XPGBWT-01-0000-00GE5 <-- where B = XP-G2 | 01 = 70 CRI Typical Out Door White.
> 
> Damn. Almost as perfect as it could have been.  There is an 80 CRI Typical but you take a Flux hit going from [R4] 130 Flux @ 350mA to [R2] 114 Flux @ 350mA. Or about 12% (192 less lumens) in my quad translated.
> 
> So a difference of 10 CRI that would be barely perceptible in the first place isn't really worth it.



Especially with night adapted (More B&W) vision.


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## Norm

Moved to LED - Norm

 What to post in the General Flashlight Discussion Sub Fourum. 



ledmitter_nli said:


> Edit: (woops meant to post in the LED forum)


If you find you've posted in the wrong forum, click the report button and request your thread be moved to the correct area. There's a very good chance staff will not see your report within your thread.


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## LEDealer

I can tell the difference between 70,80, and 90.
Look at an apple under three different sources at those CRIs and it will be very apparent.


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## ShineOnYouCrazyDiamond

A question I would ask is if you think you can tell the difference between 70 and 80 CRI when compared side to side, do you think you could tell having only one light of a certain tint if it is 70 CRI or 80CRI? I highly doubt it.

When I sit around an compare my lights side by side I an tell differences between tint even within the same tint bin. But comparison between different tints tends to make things look worse. A neutral tint can appear very cool next to a warmer tint. But I don't think I could tell differences between CRIs.


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## Esko

AnAppleSnail said:


> If all the other light characteristics are the same, not usually. It depends on the SPD of the light and which colors you are viewing by it. I find that tint and CCT are far more noticeable (And glaring, when inappropriate).



+1

I would also want to add that I did some photography tests perhaps a year ago and once I eliminated CCT (and tint) differences, it was rather difficult to tell the difference in photographs, too. There was some differences in bright reds when comparing CW to NW or WW, but not really much when comparing different versions of NW and WW. I used a presentation set of some ~150 fabric samples in the photographs (ie. the samples had some texture). Only after taking the pics I realized, that I didn't pay enough attention to keeping all lights precisely at the same angle and it was enough to disturb the comparison. I think that the only significant difference was seen in cheap CW fauxtons and even then the difference was smaller that I expected. It was somewhat disappointing.


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## Anders Hoveland

This is a bit of a meaningless question. CRI is not necessarily a great indicator of quality of light. But to answer your question, I can tell the difference between a 95CRI LED and a 97CRI neodymium glass halogen bulb. To be fair, the neodymium halogen does have a slightly higher correlated color temperature (perhaps 3250K) compared to the LED (rated 3000K), but the neodymium glass halogen still feels like it is a "softer" light. It is not extremely obvious, and you would not be able to tell at first glance. But the light is a bit different, and once you know what to look for, you can be able to identify it within a few seconds. The color rendering is also slightly different, if you do a side by side comparison. And I really feel the halogen is more comfortable for reading, whether it is with neodymium glass or without. This does not mean I could tell the difference between 95 and 97CRI if they were both LED. It is just that the quality of halogen is such that it is significantly different from LED. In other words, there is more to light than correlated color temperature and CRI. Just because two different sources have the same color temperature and same CRI does not mean the light will necessarily be the same. However, I can definitely tell the difference between 80CRI LED and 90CRI LED.


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## ledmitter_nli

Since this is the LED forum, the question references LED's. That said, I'm not sure if I want to shell out the cash at this juncture, but if I did, I would try to find if a particular binned LED with a 70 CRI and an 80 CRI looked any different myself.

Knowing I lose nearly 200 lumens of output with the higher CRI LED (in a quad array) makes me think it isn't worth the step down and I should just adopt the Nichia 219's instead.


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## Anders Hoveland

High CRI LED definitely has better light color than standard 80CRI LED, not even talking about color rendering. The red phosphor may be less efficient, but for aesthetic purposes it is worth it.


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## AnAppleSnail

ledmitter_nli said:


> Knowing I lose nearly 200 lumens of output with the higher CRI LED (in a quad array) makes me think it isn't worth the step down and I should just adopt the Nichia 219's instead.



200 lumens is nothing in a quad array for output. Most people with a side-by-side comparison can't tell 1100 from 1300 lumens. However, it does make about 10% difference in runtime, if you're targeting a given output instead of a given current.


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## SemiMan

Side by side, with the right color samples and the same CCT, yes you will be able to tell the difference. With different CCTs, nope you will have no clue between 80 and 90, though between 70 and 90 yes probably.

The key here is that you will know they will be different. I can create an 80CRI light and 90CRI light of "similar" CCT, but you may like the 80 better if I give you more color gamut and/or saturate certain appealing colors.

Semiman


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## TEEJ

SemiMan said:


> Side by side, with the right color samples and the same CCT, yes you will be able to tell the difference. With different CCTs, nope you will have no clue between 80 and 90, though between 70 and 90 yes probably.
> 
> The key here is that you will know they will be different. I can create an 80CRI light and 90CRI light of "similar" CCT, but you may like the 80 better if I give you more color gamut and/or saturate certain appealing colors.
> 
> Semiman



Excellent point.

About the other out put sacrifice related posts - 

As to out put, I just want to remind that humans are terrible at judging out put as a single variable...IE: Two lights with different out puts, shined one at a time onto a wall, may not be distinguishable.

Most posts I see about this issue focus on the concept of whether the user could tell if one light had a few more or fewer lumens, etc....and ignore whether you'd see more or not.

The primary purpose of a flashlight is to see things with...and, a brighter light will illuminate more at a time. As humans, we might see more of those THINGS with a few more lumens, just as wee sometimes argue that 0.25 lux is TOO bright and that 0.001 lux is plenty, etc.

The edges of what we see expands proportionally to the amount of light available to see it with....even if we can't TELL if its brighter or not in of itself.


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## ledmitter_nli

AnAppleSnail said:


> 200 lumens is nothing in a quad array for output. Most people with a side-by-side comparison can't tell 1100 from 1300 lumens. However, it does make about 10% difference in runtime, if you're targeting a given output instead of a given current.



Less lumens and the same run-time. The higher CRI Flux bins are still drawing the same current.

I'm keen to guess a 200 lumen difference in output is much more obvious than a 10pt difference in CRI. 200 lumens can really help the spill area. Not via a side-by-side comparison since those can be notoriously subjective depending on what color your mood ring is, but by an overlay flip by flip comparison.

I was actually somewhat mistaken about the 200 lumen difference it's more. If I went with the Q5-5C binned 80 CRI minimum (probably midway between 80 - 90) it would be 107 Flux @ 350mA. About a 17% difference or -270 lumens. Another 230 lumens less and I'm in Nichia 219 territory making the 219 a better value play for CRI.

Not that I'm thinking of doing that.  1600 lumens with the 70 CRI [R4-5C] is decent.


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## Anders Hoveland

SemiMan said:


> The only thing I am wondering is how you can be so deluded to believe that you can tell the difference between 94 CRI 93 CRI 95 or even 90.


 I can tell. It is mostly by comparison to other LED sources with known CRI ratings, and I have collected _several _of them. So, for example, if I can see the color rendering looks a little better than a Cree TrueWhite fixture, but not quite as good as high CRI PAR retrofit fixture, I conclude that the CRI must be in the range of 92-95 CRI. I look at skin tones, the appearance of red colored objects, whether various green colored objects appear deep forest green or yellowish green, and compare their appearance under halogen. When I have so many different light sources at my disposal, with a range of different CRI ratings I can use for reference, it becomes easier to say "this light source feels like it should be around 94 CRI". I am very particular and can notice subtle differences in light quality. Why should this be so surprising? There are practiced people in the industry who can instinctively differentiate between 4000K and 4100K with relative ease. I am not saying that everyone can do this, but there are people who can. When it comes to LED, I can definitely differentiate between 92 and 95 CRI. In fact, I can observe the subtle difference between 95 and 96 CRI, or the light appearance characteristics of my 96 CRI blue-emitter LED compared to a 97 CRI violet-emitter LED. It is not really _noticeable_, but it is _observable_. The closer the CRI is to 100, the easier it is to differentiate between small differences in CRI ratings. Could I tell the difference between 83 CRI and 85 CRI ? Probably not.





SemiMan said:


> I think you have deluded yourself to believe that because the light looks good it must be high CRI which is not true,.


 I am fully aware that how the light looks is not the same thing as actual color rendering. There is tint, "softness"/"harshness", beam distribution, and other qualities of the light which are difficult to quantify.



SemiMan said:


> most people prefer a bulb that is not 100 CRI,


 The CRI rating is, in one sense, rather meaningless to what type of light people prefer. Two different light sources could be completely different, have completely different spectral characteristics, but still have the same CRI rating. But the closer you get to the value of 100 CRI, the more the spectra must conform to the black body curve, so at 98 CRI there is very little variability among different light sources. The fact that people like the light from incandescent bulbs does not mean they like 100 CRI, it just so happens that an incandescent bulb has 100 CRI. You could put a filter over the light, reducing the CRI down to 90 (but not changing the tint too much) and chances are they would _still_ prefer this incandescent light over something else.



SemiMan said:


> a variety of CRI between 80 and 95 and you would have a hard time guessing within 5 to 10 CRI.


 I can tell the difference between 80 and 85 CRI, at least when it comes to LED. 80 CRI seems a little greyish, 85 CRI seem more adequate. It would probably be very difficult to tell the difference between 80 and 84 CRI, not sure if I would be able to do it. It would not be much of a problem to differentiate between 90 and 95 CRI. It's not some huge obvious difference, but it is not so hard to look at it carefully and tell, especially if they were side by side and I was comparing the two. I probably could not tell the difference between 90 and 92 CRI.


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## TEEJ

Depending on the person and the color, it would be somewhat akin to a person with perfect pitch vs being tone deaf, etc.

The vast majority of people can tell a difference between two things via the difference itself...but are unable to identify the "ranking" of those two items individually, especially if only shown ONE.

The same goes for lux, lumens, a light or sound frequency, or intensity, etc.


There are so many variables, and the brain does so many compensatory steps in interpreting what it "sees", that for example, taking a granny smith apple you have never seen before, and viewing it in an unknown light, and being asked what the CRI of the light was, would be ridiculous. All you'd be doing is interpreting the color you assumed the apple was supposed to be, and guessing if it looked more or less like that.

If you had TWO apples, and were asked if they were the same color, but were shown one on Tuesday, and the other on Wednesday...even in broad daylight, you'd be just guessing. If they were side by side in broad daylight, you might still be guessing, but, you'd have a better shot.

If you saw one Monday AM in dawn light and the other Monday night in twilight, you would also be hard pressed to guess at the difference in color.

And so forth.


And for FLASHLIGHT's, especially if USED at night, with night adapted vision, you are essentially seeing in B&W, and all the crap about CRI is a cruel joke. If NOT night adapted, it can at least still make a difference.


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## SemiMan

Ander's you are full of it.

You have no clue and if you are being truthful in your posts, you also have no equipment to measure either. You don't even have a color chart for even determining CRI. You are guessing and guesses are completely meaningless. Keep posting to make yourself feel important and knowledgeable, but keep in mind we know that not long ago you were on here arguing with people about Lux and Lumens and you were completely wrong on that and yet kept arguing.

I have done blind tests with large groups of interior designers and let them pick their materials. They know what things should look like, but not even they could tell different technology bulbs apart let alone what was high CRI or not. I have been in conferences and meetings with experts who all agree that except under well controlled tests, they can't differentiate reliably much about what is typically 85.

However, you claim to be "special" .... ok, you run with that ... those who actually know something about lighting know you are not.


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## Anders Hoveland

TEEJ said:


> The vast majority of people can tell a difference between two things via the difference itself...but are unable to identify the "ranking" of those two items individually, especially if only shown ONE.


I agree. In most cases people would not be consciously aware that the lighting in their room was 80 CRI instead of 85 CRI. That does not mean it would not affect them. Things clearly look much more colorful under 90 CRI illumination than 70 CRI illumination. Working under 70 CRI light all day, it would be like the life had been sucked out of the room, it would get a little dreary. Higher CRI is better. 73 CRI is better than 70. There is incremental benefit, even if the benefit is too small to notice.

Or I will put it to you another way. No one can tell the difference between 70 and 73 CRI. But maybe some people could tell the difference between 70 and 78 CRI, but they could not tell the difference between 73 and 78 CRI. So using this type of indirect argument, we could logically deduce that 70 CRI is indeed worse than 73, and that it's not a completely insignificant difference.




TEEJ said:


> And for FLASHLIGHT's, especially if USED at night, with night adapted vision, you are essentially seeing in black & white, and all the crap about CRI is a cruel joke. If NOT night adapted, it can at least still make a difference.


That's one way to look at it. Another way to look at it is that color rendering might even be _more _important, since the eye has more trouble discerning color at low light levels.

(particularly referring to red-green color contrast here)


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## SemiMan

Anders Hoveland said:


> I agree. In most cases people would not be consciously aware that the lighting in their room was 80 CRI instead of 85 CRI. That does not mean it would not affect them. Things clearly look much more colorful under 90 CRI illumination than 70 CRI illumination. Working under 70 CRI light all day, it would be like the life had been sucked out of the room, it would get a little dreary. Higher CRI is better. 73 CRI is better than 70. There is incremental benefit, even if the benefit is too small to notice.
> 
> Or I will put it to you another way. No one can tell the difference between 70 and 73 CRI. But maybe some people could tell the difference between 70 and 78 CRI, but they could not tell the difference between 73 and 78 CRI. So using this type of indirect argument, we could logically deduce that 70 CRI is indeed worse than 73, and that it's not a completely insignificant difference.
> 
> 
> 
> That's one way to look at it. Another way to look at it is that color rendering might even be _more _important, since the eye has more trouble discerning color at low light levels.
> 
> (particularly referring to red-green color contrast here)




... and you keep extolling your ignorance. "Colorful" comes from gamut, not CRI. I could easily prepare a much more "colorful" light of lower CRI than a less "colorful" light.


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## Anders Hoveland

SemiMan said:


> ... and you keep extolling your ignorance. "Colorful" comes from gamut, not CRI.


I was just referring to the fact that higher CRI white LEDs generally tend to have better red-green color contrast, so are indeed more colorful. 

Yes, you are right, CRI is not quite the exact same thing as "colorful". But I would argue they are very similar, in many ways.
Let me give you an example: Cyan is not really one of the pure primary colors, but to get maximum color saturation from cyan colored objects you really need cyan wavelengths of light. Simply using a combination of royal blue and green wavelengths will not work, because both royal blue and green wavelengths have too much overlap with the red color receptors in the eye, which would cause the cyan color rendering to appear too greyish. We can see this on a CIE color coordinate graph, the perimeter going from the green point of the triangle to the blue point bends outwards to some degree, giving it some further color distance from the red.


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## SemiMan

It is "not quite" it is not at all. 2200k 100 cri is not colorful and really even 2700k is not in an environment with blue colors.

Posted by really crappy Tapatalk app that is questionable wrt respect of personal data.


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## Anders Hoveland

SemiMan said:


> 2200k 100 cri is not colorful and really even 2700k is not


That probably may be a reason why it is easier to make higher CRI LED phosphors for lower correlated color temperatures.


It is really outside the scope of this discussion, but I have wondered whether it could theoretically be possible to make a spectrum with_ better_ color rendering than one perfectly emulating a black body curve. Where all the colors would be rendered approximately the same, but there would be higher color contrast.


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## markr6

I can tell a huge difference between the Cree 80CRI and 93CRI bulbs. I stopped buying the 80CRI because of this. It costs more up front, but I KNOW when I hit the switch I know I made an effort to get better lighting and like that peace of mind.


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## HarryN

My eyes are nothing special when it comes to color vision but I would say my wife's are pretty dang good. Nonetheless, both of us clearly can tell the difference between LEDs of substantially different CRI and CCT, no question.

As pointed out earlier, red, green and deep blues are excellent ways to color test a light source. Try grilling a steak with a couple of lights and see which one works the best for you. Walk around the backyard or a garden with some flowers. Shine the light on some bottles of liquid soaps and various liquids around the house. I would be surprised if you don't observe a significant difference.

It is correct that true night adapted eyes see colors and details differently than ones which are not. At the same time, it takes quite a while for this effect to fully kick in. The vast majority of my own flashlight use is not with anything close to night adapted eyes, but more likely just lighting up shadowed areas. 

For more general LED lighting use, there is a greater likelihood to compare the light to mid afternoon sunlight. In my daughter's case, she was ecstatic when I converted a small fluoro tube light into a very high CRI 4000K light using Philips Rebels. She used that desk light for reading school books and really gave it a work out.


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## Anders Hoveland

HarryN said:


> For more general LED lighting use, there is a greater likelihood to compare the light to mid afternoon sunlight. In my daughter's case, she was ecstatic when I converted a small fluoro tube light into a very high CRI 4000K light using Philips Rebels. She used that desk light for reading school books and really gave it a work out.


How high was the CRI exactly? Just curious.


80CRI LED is okay for hall lighting.


I have an admission to make. I was looking at the difference between two high CRI LEDs, one rated 95 CRI and the other 96 CRI, I am not entirely sure I can tell the difference. It seems like there might be a difference, it is just a little too small to be sure, seems like the difference might just be one notch less than what I can discern. It's sort of a twilight zone, I would not say I am seeing absolutely no difference between the two either. I just cannot differentiate between the two with any consistency/reproducible precision. If you understand what I am trying to say. I think I could probably discern the difference between 94 and 96 CRI though, with careful observation and comparison, unfortunately I do not actually have any 94 CRI LEDs to test this theory.


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## SemiMan

Anders Hoveland said:


> I have an admission to make. I was looking at the difference between two high CRI LEDs, one rated 95 CRI and the other 96 CRI, I am not entirely sure I can tell the difference. It seems like there might be a difference, it is just a little too small to be sure, seems like the difference might just be one notch less than what I can discern. It's sort of a twilight zone, I would not say I am seeing absolutely no difference between the two either. I just cannot differentiate between the two with any consistency/reproducible precision. If you understand what I am trying to say. I think I could probably discern the difference between 94 and 96 CRI though, with careful observation and comparison, unfortunately I do not actually have any 94 CRI LEDs to test this theory.



Ego or delusion I am curious? ... or a little of both?

You ... no one really, can tell the difference between 94 and 96 if they are exactly the same CCT and similar spectrums. If you see any difference its a CCT difference, not CRI and you would have no clue what was 94 and 96 without highly tailored color swatches, and a perfect 100 CRI source for comparison ...... AND .... even then your visual memory is really hard pressed to remember exactly what is what.

Semiman


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## Anders Hoveland

SemiMan said:


> You ... no one really, can tell the difference between 94 and 96 if they are exactly the same CCT and similar spectrums. If you see any difference its a CCT difference, not CRI


You know, it might not actually be color rendering I am seeing. When the CRI of a white LED starts getting up to really high values, like ≥95, the quality of the light starts changing, it becomes a little "softer" or more like an incandescent bulb or natural sunlight. Difficult to describe.
It feels a little less like "LED light".


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## ShineOnYouCrazyDiamond

I'm with DemiMan on this thread. I think the claims being made here are just not possible with the human eye unless highly trained and backed up by scientifically proven and tested double blind tests. What you are seeing is more likely than not the subtle tint differences between the LEDs even in the same bins.


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## markr6

ShineOnYouCrazyDiamond said:


> I'm with DemiMan on this thread. I think the claims being made here are just not possible with the human eye unless highly trained and backed up by scientifically proven and tested double blind tests. What you are seeing is more likely than not the subtle tint differences between the LEDs even in the same bins.



I would agree to that to some extent; maybe talking about a small change like 80CRI vs 85CRI. But definitely not in my case. The 80 vs 93 is huge. I can look at any object and notice the difference right away. I can even notice it in my nearly empty office (4th bedroom) with plain khaki walls - they are pretty accurate with the 93CRI bulbs but some odd color beige with the 80CRI. Same with the hallways and carpet throughout the home. I really need to switch out more ceiling lights but want the cost to come down.


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## ShineOnYouCrazyDiamond

markr6 said:


> I would agree to that to some extent; maybe talking about a small change like 80CRI vs 85CRI. But definitely not in my case. The 80 vs 93 is huge. I can look at any object and notice the difference right away. I can even notice it in my nearly empty office (4th bedroom) with plain khaki walls - they are pretty accurate with the 93CRI bulbs but some odd color beige with the 80CRI. Same with the hallways and carpet throughout the home. I really need to switch out more ceiling lights but want the cost to come down.



But that's kinda my point. How do you know that the 80CRI and 93CRI lights don't have different tints or other variences that could play into color change other than just CRI? 

Not saying you don't amazing eye or anything, personally my eyes the differences between some greens and greys - so I don't ever claim to be able to tell differences like this. I just go with what is comfortable to my eyes.


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## SemiMan

Anders Hoveland said:


> You know, it might not actually be color rendering I am seeing. When the CRI of a white LED starts getting up to really high values, like ≥95, the quality of the light starts changing, it becomes a little "softer" or more like an incandescent bulb or natural sunlight. Difficult to describe.
> It feels a little less like "LED light".



Or more likely it is just measurement bias.

When given a choice, 100CRI IS NOT the preferred light source. People consistently rate lights off the blackbody (i.e. not 100 CRI) as preferred to lights on the blackbody. 

The reality there is nothing "natural" about 2700K or 3000K incandescent light. Outside of manmade sources, we never experience it in nature. Fires are not 2700 or 3000K (and not 100CRI unless all you have left are embers). Sunlight when it is 2700 or 3000K is far from 100CRI ... Incan has less blue which when directly viewed could result in less perceived glare, but sunlight of course has lots.


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## markr6

ShineOnYouCrazyDiamond said:


> But that's kinda my point. How do you know that the 80CRI and 93CRI lights don't have different tints or other variences that could play into color change other than just CRI?



Because I've tried over a dozen bulbs and they are always consistent between the 40W 80CRI and 40W 93CRI. Of course I could have gotten two sets with matching yet different tints, but I doubt it.


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## SemiMan

markr6 said:


> I would agree to that to some extent; maybe talking about a small change like 80CRI vs 85CRI. But definitely not in my case. The 80 vs 93 is huge. I can look at any object and notice the difference right away. I can even notice it in my nearly empty office (4th bedroom) with plain khaki walls - they are pretty accurate with the 93CRI bulbs but some odd color beige with the 80CRI. Same with the hallways and carpet throughout the home. I really need to switch out more ceiling lights but want the cost to come down.



Define "accurate". A halogen bulb is not "accurate" it is a halogen bulb. Colors will look drastically different in sunlight than with a halogen bulb. Is the halogen bulb still accurate?

This is why lighting people are trying to move away from CRI as it is equated with accuracy but all it describes is compliance with a black body radiator which never exists except in man-made conditions under 5000K and is defined as sunlight spectra above 5000k.

I can make a wide gamut 85CRI bulb that you are likely to prefer to a 93CRI bulb. It won't replicate a halogen source, but it will allow better definition on a wider range of colors. Depending on the color of your carpets, there is a good chance you would prefer them under 4000K, 85CRI to 93CRI at 2700 or even 100CRI at 2700K. How do those navy blue socks look in 100 CRI 2700K?

Semiman


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## markr6

SemiMan said:


> Define "accurate". A halogen bulb is not "accurate" it is a halogen bulb. Colors will look drastically different in sunlight than with a halogen bulb. Is the halogen bulb still accurate?
> 
> This is why lighting people are trying to move away from CRI as it is equated with accuracy but all it describes is compliance with a black body radiator which never exists except in man-made conditions under 5000K and is defined as sunlight spectra above 5000k.
> 
> I can make a wide gamut 85CRI bulb that you are likely to prefer to a 93CRI bulb. It won't replicate a halogen source, but it will allow better definition on a wider range of colors. Depending on the color of your carpets, there is a good chance you would prefer them under 4000K, 85CRI to 93CRI at 2700 or even 100CRI at 2700K. How do those navy blue socks look in 100 CRI 2700K?
> 
> Semiman



All that matters is that it's "accurate" to the wife after we spent $600 on paint and hours, days, or weeks arguing which of the 27 shades of "tan" looked nice in the house. We get way to technical here when sometimes "accurate" is just simply when you achieve the desired intent. When others walk into my home, they also like the paint color and it just looks right with all the other decor.


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## Anders Hoveland

ledmitter_nli said:


> Can you tell the difference between 70 and 80 CRI? 80 to 90 CRI?



I have already posted these links in another thread, but these pictures may give you some rough idea of how color rendering appears under lighting with different CRI values:

http://www.donsbulbs.com/bulbs/g623/glossary/cri.examples.jpg
http://2bora.com/wp-content/uploads/cri-lamps-new.jpg
http://www.fosilum.si/static/uploaded/htmlarea/cri-comparison.jpg
http://www.naturalux.com/CRI Examples.html
http://www.fusionlamps.net/assets/img/CRI-comparison-apples.jpg




ShineOnYouCrazyDiamond said:


> What you are seeing is more likely than not the subtle tint differences between the LEDs even in the same bins.


It might be possible this could be a factor. I have noticed that higher CRI LEDs generally tend to have better tints also. And a good tint can really make the light seem nice, even if it does have a lower CRI. However, I am just not entirely sure about your theory. I have two LED bulbs (rated 85 CRI), exactly the same otherwise , but with substantially different tints, and they both seem to have about the same CRI to me. 

In some situations, improving the color tint could even throw the CRI value off a little bit, because LED light is not really a full spectrum source. I have a really high CRI LED bulb that looks like the tint should be just a little more green. But the reason the tint seems a little off is because the spectrum lacks the cyan wavelengths found in a full spectrum source. If the phosphor formulation included a greater ratio of green to achieve a better tint, that might begin to throw the color rendering off, and turquoise and yellow colors would be rendered a little too greenish.




SemiMan said:


> The reality there is nothing "natural" about 2700K or 3000K incandescent light. Outside of manmade sources, we never experience it in nature.


I disagree with you. Sometimes men can improve upon nature, and the incandescent bulb is definitely a case where that happened. Incandescent light to humans is basically the equivalent of fire in my opinion, though brighter white, and thus a little more like sunlight to some degree (at least compared to the extreme orange color of fire).

It is in interesting, when incandescent bulbs first became widespread, there were some people who complained that the light was too harsh, as they were accustomed to the softer light from their gas lamps.

You know, SemiMan, 2800K light sources were already widespread in the late nineteenth century, in the form of lime lights and gas mantle lamps.




SemiMan said:


> 3000K is far from 100CRI


It is true that 3000K sunlight (like for example at dawn) is substantially different from 3000K incandescent light. Most people might not realize this but the spectrum of sunlight does not really follow the same spectral distribution as a true black body curve. The sun actually gives off a very bluish 5800K black body spectrum, which is later attenuated down to a more warmer color as it passes through the atmosphere (Rayleigh scattering, proportional to the _fourth_ power of the wavelength being scattered).


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## SemiMan

markr6 said:


> All that matters is that it's "accurate" to the wife after we spent $600 on paint and hours, days, or weeks arguing which of the 27 shades of "tan" looked nice in the house. We get way to technical here when sometimes "accurate" is just simply when you achieve the desired intent. When others walk into my home, they also like the paint color and it just looks right with all the other decor.



This is why I always check paint chips against both sunlight and different bulbs before I pick which one I want. I have specifically gone higher CCT (was not even possible in halogen/incan) because I loved the color in sunlight, but it looked like absolute crap in halogen/incan. It was a nice shade of green/blue. My kitchen is lit with 4000K, and the paint was picked taking this into account. Bedrooms .. 2700K ...they are for sleeping, and again, paints that work in high/low CCT (think browns/reds).

What is "right" is not necessarily high CRI ... In many cases (most?), good CRI and the right CCT can have a far bigger impact.

Semiman


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## SemiMan

Anders Hoveland said:


> I disagree with you. Sometimes men can improve upon nature, and the incandescent bulb is definitely a case where that happened. Incandescent light to humans is basically the equivalent of fire in my opinion, though brighter white, and thus a little more like sunlight to some degree (at least compared to the extreme orange color of fire).
> 
> It is in interesting, when incandescent bulbs first became widespread, there were some people who complained that the light was too harsh, as they were accustomed to the softer light from their gas lamps.
> 
> You know, SemiMan, 2800K light sources were already widespread in the late nineteenth century, in the form of lime lights and gas mantle lamps.
> 
> 
> 
> It is true that 3000K sunlight (like for example at dawn) is substantially different from 3000K incandescent light. Most people might not realize this but the spectrum of sunlight does not really follow the same spectral distribution as a true black body curve. The sun actually gives off a very bluish 5800K black body spectrum, which is later attenuated down to a more warmer color as it passes through the atmosphere (Rayleigh scattering, proportional to the _fourth_ power of the wavelength being scattered).



- The gas lamps were "softer" because they were A) not as bright and B) not nearly as intense with fairly large mantles compared to the clear bulbs and relatively small filaments.

However, nothing is natural about either a gas fire OR an incandescent bulb. Pre the invention of these technologies, almost no one on the planet, for any period of time, had ever been exposed to light of this nature. Normal fires do not burn this hot.

Certainly we have had 0 chance to evolve to adapt to this style lighting and if we did, then Asians would like this color too .. but for the most part they prefer cooler now that it is available .. and is not 100 CRI.

AND AGAIN ... AND I AM SHOUTING CAUSE YOU KEEP IGNORING REALITY ... WHEN TESTED, PEOPLE ALWAYS PREFER LIGHT THAT --- IS NOT ON THE BLACKBODY --- i.e. LIGHT THAT IS NOT 100 CRI.

Oh, and nice to see you have been reading about Rayleigh scattering on Wikipedia but the fact you felt quoting was meaningless to our discussion.


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## SemiMan

OH! .... and it is not 3000K at sunrise and sunset due to Rayleigh scattering .....


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## Anders Hoveland

SemiMan said:


> This is why I always check paint chips against both sunlight and different bulbs before I pick which one I want.


Just curious, do you think, or know whether those paint chips use exactly the same type of pigments and have the same spectral absorbance pattern as the paint they actually sell ? 
In other words, even though the paint chip sample and the paint may be the same color under sunlight, will they also appear identical to each other under fluorescent lighting?


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## markr6

SemiMan said:


> This is why I always check paint chips against both sunlight and different bulbs before I pick which one I want. I have specifically gone higher CCT (was not even possible in halogen/incan) because I loved the color in sunlight, but it looked like absolute crap in halogen/incan. It was a nice shade of green/blue. My kitchen is lit with 4000K, and the paint was picked taking this into account. Bedrooms .. 2700K ...they are for sleeping, and again, paints that work in high/low CCT (think browns/reds).
> 
> What is "right" is not necessarily high CRI ... In many cases (most?), good CRI and the right CCT can have a far bigger impact.
> 
> Semiman



Every single subject I tested under my high CRI bulbs looked "right" though, so I'm batting 100% right now...I won't be playing around with any more ~80CRI bulbs (just tried my last one last night...it was junk). And I always pass on the paint chips and actually paint a 4x4 area of the wall to get a better idea of how it will look.


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## SemiMan

markr6 said:


> Every single subject I tested under my high CRI bulbs looked "right" though, so I'm batting 100% right now...I won't be playing around with any more ~80CRI bulbs (just tried my last one last night...it was junk). And I always pass on the paint chips and actually paint a 4x4 area of the wall to get a better idea of how it will look.



I painted a wall once 4 time because it kept looking good in one light and bad in the other. The two sources were sunlight and incandescent light. That is when I went for the better solution. I liked the colors, but it was the incandescent with lack of gamut that made it look bad. Got rid of that and all was good ... even without 100CRI.

Some people also prefer warmer tones.


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## HarryN

Anders Hoveland said:


> How high was the CRI exactly? Just curious.
> 
> .



IIRC, that particular Rebel LED had a CRI approx. 90 and a CCT around 4000 - 4100. Of course now I cannot find it on the Lumileds web site, perhaps the phos it took to do that conversion was too inefficient to keep marketing.


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