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

By casual observation is there a big difference?

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

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).

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.

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.

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.

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

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)

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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.

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.

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.

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).

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+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.

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.

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.

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.

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.

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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.

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

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

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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.

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.

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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.

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.

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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,.

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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,

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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.

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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.

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.

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.

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.

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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.

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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)