Does HCRI have the same effective color rendering as an incandescent?

[plaguem]

i think i've done a fair share of research around these parts on tint (and tintsnobbery of course). i haven't found an answer for this yet so i'm putting this out here. watched a few of marshall's light testing videos against his 4D maglite and it seems like incandescent is yellower.

would a kind soul perhaps do a beamshot comparison and post it here?

 

[jorn]

When you talk about yellow, orange, blue, green etc. you describe tint. Dont mix tint and cri, it's not the same. Incans got 100 cri, the best leds got 92 cri.

 

[tobrien]

I think it's supposed to be close. I'm not an expert, though.

I'd imagine there have got to be varying qualities of color rendition on incans though (i.e: a run-of-the-mill Mag output/tint versus a Surefire incandescent bulb (P60?) that probably costs alone just as much as the Maglite did). dunno though

 

[Flashlight Dave]

One must factor in tint with color rendering. And orange incan light is still orange and will give a different color rendering than say sunlight at 5600K

 

[AnAppleSnail]

There are a fair number of threads doing this. I'm on lunch, so I'll grab a few. My understanding is:

0. Most lights are analyzed and compared to blackbody sources. This lets scientists model them fairly easily, but it does not describe light well. CCT tells you what blackbody it is like, and CRI tells you how like that BB it is.

1. All discussion of color perception is valueless without using objective results OR standardized subjective studies. I can show you a 630 nm LED that is 'Red as red,' until I show you a 660 nm red. Then the old red is so orange you'd call it a yellow-orange US caution light, not red.

2. Sunlight is markedly different from radiation from a black-body source. It has spectral lines coming from the star and is filtered and scattered. Further, 'Sunlight' at the ground varies based on weather, time of day, elevation, latitude, and time of year.

3. Color perception is complex. "Color Rendering Index" certainly does not capture the full gamut of color perception, nor of white light perception. Different CCTs of black-body-like radiation are appropriate for different tasks, and the human body takes important circadian cues from changing CCT throughout the day and night.


CRI of White LEDs
Making a desk lamp
"When 2700K is not 2700K"
What Color Spectral Power Distribution produces the best photography?
Ultimate Light Bulb Test: Incan, Fluoro, LED


Now for my experiences:

1. Incandescent light changes dramatically depending on whether the bulb is driven over, at, or under its rated voltage. Most people classify these as:

Under: Yellow or orange (CCT is 2300K to maybe 3000K? Wild guess)
At: Yellow or white (Great, huh? This is the trouble with such subjective views, CCT is 2800K to maybe 3500K)
Over: Pure white (3500K to 4000K? I forget when tungsten melts)

I know of some LEDs that could match each of these conditions. However, LEDs have CCT, CRI, and tint bins as well, and their tint and CCT change greatly with varying drive current and temperature. Cree tint bins tend to be big enough to park six trucks on, but I find that:

1. "High CRI" warm white Crees look rather like underdriven or correctly-driven filaments. Depends on who you are and what filaments you look at.
2. "Neutral white" Crees (Especially, to my eyes, in the 5A to 3C range) look like correctly- to over-driven filaments.
3. "High CCT" high CRI LEDs, like Nichia's well-known offering, look much like near-noonday sunlight to my eyes. But it would depend on the day.

Sadly, I can't find the two I had in mind. Harrumph.

 

[mvyrmnd]

1. "High CRI" warm white Crees look rather like underdriven or correctly-driven filaments. Depends on who you are and what filaments you look at.
2. "Neutral white" Crees (Especially, to my eyes, in the 5A to 3C range) look like correctly- to over-driven filaments.
3. "High CCT" high CRI LEDs, like Nichia's well-known offering, look much like near-noonday sunlight to my eyes. But it would depend on the day.

I agree with those sentiments entirely. I love the 7A3 90CRI XP-G (3000k) is it gives all the lovely warm light of an incan, with good colour rendition, with all the benefits of LED.

I have found, though, that during the day, it can look quite odd, and using a 219-based light during the day seems more normal, with it's 4500K output.

 

[plaguem]

When you talk about yellow, orange, blue, green etc. you describe tint. Dont mix tint and cri, it's not the same. Incans got 100 cri, the best leds got 92 cri.

Got it.

I think it's supposed to be close. I'm not an expert, though.


I'd imagine there have got to be varying qualities of color rendition on incans though (i.e: a run-of-the-mill Mag output/tint versus a Surefire incandescent bulb (P60?) that probably costs alone just as much as the Maglite did). dunno though

this is new to me. i genuinely didn't know there were different cri levels between different incan bulbs. gosh. learning everyday.

One must factor in tint with color rendering. And orange incan light is still orange and will give a different color rendering than say sunlight at 5600K

There are a fair number of threads doing this. I'm on lunch, so I'll grab a few. My understanding is: ....

thanks! good points and a good read. i've never heard of the term blackbody sources. i'll google it. good links too. i'm at work now so i'll read them bit by bit as i go along. again didn't know that incans had different cri levels. makes sense though.


your point about sunlight being different depending on weather, time of day.. etc, i was pondering the same thing. i've always thought that noonday sunlight looked the best. several times i've brought my weak old pelican incan out at midday and compared it and the incan looked too yellow/too-hcri/low-cct for my liking. led me to think if HCRI lights are like incan, then i don't want HCRI. but as it turns out i may want nichia. :)

I have found, though, that during the day, it can look quite odd, and using a 219-based light during the day seems more normal, with it's 4500K output.

i agree with this. i think i'll start looking into getting my first nichia light.

 

[HotWire]

I have built many hotwires as well as Nichia 219 (some triples). They are all a little different. My hotwires tend to be modded and are really bright. Both the Nichia 219 and my hotwires look similar, but differ in throw, color rendition, brightness. The high cree LEDs and the Hotwires both have their place. I would select the light that you like for your application. Most of my hotwires have large batteries and are.... a little heavy. My high-cri lights are mostly small and easy to carry and use.

 

[Yoda4561]

this is new to me. i genuinely didn't know there were different cri levels between different incan bulbs. gosh. learning everyday.

Ahh, there aren't really, but there are different CCT's, and this can affect your perception of color more than CRI in most cases.

 

[AnAppleSnail]

Ahh, there aren't really, but there are different CCT's, and this can affect your perception of color more than CRI in most cases.

It turns out that we (Fixed lighting) have plenty of discussion of filtered incan bulbs, too. If you re-reflect the IR back into the bulb, you get a higher CCT. This makes a greenish tint effect by changing the CCT somewhat. There's also yellow-filtering ones to make "whiter white." Taken to extremes, this makes those ugly kool-aid-blue headlight bulbs you see on cars owned by foolish people. The filament isn't much different in either case, but the spectrum escaping is definitely different.

 

[the.Mtn.Man]

As far as I'm concerned, LED technology will have been perfected when we have 3200K emitters with a CRI of 100. My high CRI HDS Rotary with its 3700K tint and 90+ CRI is very good and vastly superior to cool white in my opinion, but it simply can't compete with a good incandescent source.

 

[twl]

CRI ratings are based on the color rendering for their CCT.
So, therefore, by definition, the CRI is only relevant when comparing against other sources of the same CCT.
The "2700K incandescent bulb with 100 CRI" is ONLY 100 CRI with respect to other lights in its CCT, and so it is of no use as a "standard comparator" unless you are using a source which is 2700K CCT.

Basically what it is saying is that "this 2700K 100 CRI bulb renders colors as well as our reference 2700K source". It is not making ANY statement about how "overall accurate on a scale of all CCT sources" it is, or anything like that.