How can something be near perfect CRI with a big blue spike?

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iamlucky13
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djozz wrote:
There is another reason to not want that blue spike, not colour rendition but the influence of blue light on our mood. There is some research on that, the effect may not be huge or worrying, and the definitive facts are not out there yet, but since it is picked up by public opinion as real and dangerous, led manufacturers have no other option than respond with leds that do not have that blue peak.

The research is clear that overall blue light exposure affects melatonin production. Maybe there is some out there, but I have not yet seen research on the effect of the blue spike specifically.

That means for example, at the same color temperature and brightness, would a light source better mimicking a black body spectrum cause less melatonin disruption than one with the spike.

Personally, I suspect not, because although the spectrum of most white LED’s is exaggerated right at 450nm, it is weak below 430nm and somewhat weak in the 470-500nm range, so the average emission across the full blue-violet range of the spectrum works out to about the same amount of total luminous energy.

jon_slider
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djozz wrote:
manufacturers have no other option than respond with leds that do not have that blue peak.
if the need is for cool white.. with no blue peak.. I dont know

I asked google whether warm white eliminates the blue peak, she said yes. Smaller blue peak in warm white, bigger blue peak in cool white.

staticx57 wrote:
… Oslon 3000k 95 CRI. …

… Nichia E21A 6500k R9080

I like warm white for relaxing before bed

I like cooler light when Im daylight adapted.

Dalamar
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thefreeman wrote:
Not much I’d say, what the data shows is that blues are more saturated and tend towards purple (color vector graphic), in reality I think this is difficult to see.

Edit :

Quote:
Related question: How much does it matter that virtually no white LEDs have proper extension into the 700 nm+ range?

I don’t think we can see 700nm


We can see 380-750nm, but we’re already not perceiving 660nm very well afaik. It’s on a curve.

As to the melatonin problem, 300 mcg is cheap and works. Lot cheaper than buying good lighting.

I only like high CRI. Collection:

Fireflies NOV-MU 21 4500k E21A

Fireflies ROT66 219B SW45 D220

Fireflies E07 Copper 219B SW45k? (odd/higher lumen bin with lower r9 and higher cct?)

Fireflies E07 219B SW45k

Fireflies E07x Pro sst20 FA4 4000k 

 

Varmint removal:

Convoy M21A C8 ver SST20 4000k (5a)

Convoy S2+ SST20 4000k  FB4 (3200ma)

Memes:

BLF GT94

Emisar D18 660nm SST20 

 

 

CRI test dump https://drive.google.com/drive/folders/1kcl_uOhgfpR4RSsa8F4b-UUVP9mkL6Cr...

rngwn
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I wonder in terms of impacts on sleep-wake cycle, how much differences between the blue-chip LEDs with blue peak concentrated at 450nm, and one that doesn't have a peak, but has some of its blue spectrum in the near-UV and violet region (i.e. 400/430nm) instead?

 

My current impression is that, both will emit approximately the same amount of "blues", but one is simply shifted into more violet territory. Admittedly, many of these violet LEDs will comes with cyan phosphors, which will emit the less energetic blues (i.e. cyan) as well.

Dalamar
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rngwn wrote:

I wonder in terms of impacts on sleep-wake cycle, how much differences between the blue-chip LEDs with blue peak concentrated at 450nm, and one that doesn’t have a peak, but has some of its blue spectrum in the near-UV and violet region (i.e. 400/430nm) instead?


 


My current impression is that, both will emit approximately the same amount of “blues”, but one is simply shifted into more violet territory. Admittedly, many of these violet LEDs will comes with cyan phosphors, which will emit the less energetic blues (i.e. cyan) as well.


sunlike , thrive, optisolis eco sol exist, but i don’t think it matters as much as (people) claim. and by people, i mean the ones trying to sell crap…

They have more accurate color, but ultimately, still don’t look like sunlight, and I sincerely doubt that blue spike matters (if it did, it’s still cheap to buy melatonin)
You would need a 2000k light to avoid blue, and in modern life its pointless, your screen, case leds, phone, etc, they all emit blue.

I only like high CRI. Collection:

Fireflies NOV-MU 21 4500k E21A

Fireflies ROT66 219B SW45 D220

Fireflies E07 Copper 219B SW45k? (odd/higher lumen bin with lower r9 and higher cct?)

Fireflies E07 219B SW45k

Fireflies E07x Pro sst20 FA4 4000k 

 

Varmint removal:

Convoy M21A C8 ver SST20 4000k (5a)

Convoy S2+ SST20 4000k  FB4 (3200ma)

Memes:

BLF GT94

Emisar D18 660nm SST20 

 

 

CRI test dump https://drive.google.com/drive/folders/1kcl_uOhgfpR4RSsa8F4b-UUVP9mkL6Cr...

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