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Discussion Starter · #1 · (Edited)
Just a brief "update" on some technical things regarding spectrum and interactions:
http://www.ledsmagazine.com/article...d=EnlLEDsJune222016&eid=327187166&bid=1441027


and a "political" statement re: color fidelity..;)
http://www.ledsmagazine.com/article...d=EnlLEDsJune222016&eid=327187166&bid=1441027
In this case, the burden of proof clearly falls on those claiming "CRI 80 is good enough." They would need to show that people cannot see the color rendering errors produced by such products, or, alternatively, that the visible color distortion is judged by consumers as an appropriate way to produce the invisibly small resultant gain in raw lumens. They do not show proof, for a simple reason - it is simply not true.

The "good enough" advocates repeatedly say that since people are buying 80-CRI lamps today, the lighting quality must be fine. At the same time, some mainstream manufacturers, while objecting vigorously to the proposed California standards, are aggressively marketing high-efficacy, high-color-rendering phosphors. Furthermore, most mainstream manufacturers offer products with CRI above 90. The current misadventure into poor-color-fidelity light sources, whereby inferior LEDs are being purchased, is merely an indicator of both human adaptability and a poorly informed marketplace that doesn't really understand or fully appreciate the choices or the possibilities.

And one more re: "red"
http://www.ledinside.com/products/2016/6/cree_expands_led_portfolio_for_horticulture_lighting

The XQ-E Photo Red LED is capable of delivering more than 6.4 μmol/sec of the 660nm peak wavelength light that can be beneficial for plant growth from a 1.6mm x 1.6mm footprint. Cree’s white and color LEDs deliver the full spectrum of light and mimic natural sunlight. Cree’s color LEDs, including royal blue, green, red, photo red and far red LEDs, deliver high PPF in the wavelengths best-suited for the different stages of plant growth.
 

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A "political" response to the CRI statement:
Salt water tanks have long lights that cannot possibly have a CRI that is even close to 80, and this is the preference of those fish keepers. I think the CRI is as important as the fish keeper thinks it is, and equally as unimportant as the fish keeper thinks it is.
 

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Discussion Starter · #3 · (Edited)
The color rendering index (CRI) refers to the bulb's ability to render individual colors accurately. The higher the CRI the more natural and vibrant the colors will look. A bulb with a CRI of 85 or higher is excellent being that the sun has a CRI of 100. To give you the best color rendition (CRI rating) and bring out the natural beauty of aquarium fish and plants in both freshwater and marine tanks, choose a 6500K daylight bulb with a CRI of at least 85.

We carry only the highest quality metal halide lamps on the market from many different manufacturers such as Radium, Ushio & Eye Iwasaki insuring the lamp has been tested, and is represented accurately as color temperature. Eye Hortilux makes 90 - 92 CRI bulbs that are excellent for both planted and reef aquariums.
:)

metal halide question - Reef Builders

175W 10000K METAL HALIDE SINGLE ENDED BULB—USHIO/HAMILTON

This German-made Ushio/Hamilton 10000K metal halide bulb offers excellent coloration and intensity. Crisp Ice White appearance, full spectrum - the combination of different wavelengths produce different colors in the spectrum and appear to the naked eye as crisp ice white light. Significantly brighter than U.S. made 10000K bulbs. This bulb has a heavy concentration wavelength spike in the 420 and 460nm (nanometer) range with additional concentration spikes in the 380nm, 550nm and 580nm wavelengths. Tested in Germany—simulates natural daylight as in the ocean at depths up to 13 feet. Longer life—TRUE-10000K Metal Halide has an exceptionally high rated life. Very High Color Rendering Index of 95 CRI. Actinic supplementation may be used to create a bluer look. An excellent choice for nano-reefs and other reef tanks up to 18" deep. on how the different Kelvin ratings appear and more information on metal halide bulbs.
10000K Metal Halide Bulb - German Ushio, Mogul Base

Wattage: 150W
Color: 10,000K, 14,000K, 20,000K, 10K, 14K, 20K
Base: R7s, RX7s DE Double Ended
Bulb Diameter: 22.6mm
Maximum Overall Length: 136mm
Color Rendering Index: 10K CRI 85, 14K CRI 65, 20K CRI 75
Average Rated Life: 6000 Hours
Metal Halide-Tubular-Double Ended
Ballast: M81/E, M/81
UV Block, Stop
http://www.replacementlightbulbs.com/lampmh150de10k14k20k.html
Many "white" LED's don't even get 75CRI.. esp.. RGB "white"..

Personally, CRI is always important.. ;) even it is to purposely ignore it.. ;)

Fortunately, most lighting that is visually pleasing to us is also good for plant growth. You do not have to suffer through a "pink" grow bulb, nor a cheap "green" fluorescent bulb, nor a "washed out" metal halide - even though all these will grow plants just fine.

Happy lighting.
http://www.plantedtank.net/forums/10-lighting/194764-cri-vs-color-temperature.html

On a side note I took the x-rite test....
;)

Color Test

If you want to see where you stand in your ability to perceive colors, take this color test: X-Rite Color Test
Maybe it helps explain my anal-ness...

http://www.xrite.com/online-color-test-challenge
 

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Discussion Starter · #4 ·
Why CRI is Important, or How to Make LED Lighting Look Great - Reef Central Online Community
For some silly reason someone started making LEDs for aquariums with low CRI cool white bulbs and it caught on (probably all that was available at the time). Then people wanted colors back that they used to have, because full spectrum lighting is available with both metal halides and T5, so they started adding color outside cool white and royal blue, striving to have all the colors show up accurately, then manufacturers (like ecotech) emulated this, and started selling fixtures that used this same idea, one that was flawed to begin with.
Also note that not all reefs are at that 30 meter mark, many are much much less and a lot are exposed to the air during low tide. The colors of a shallow water reef are closer to the appearance we strive for in our tanks because that 90 foot deep reef looks blue and dull until lit by high powered flash from a camera. The point is that for our tanks the high CRI is an important feature of good lighting, unless you are going for that dull blue look.
2012................
 

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@jeffkrol

I guess I don't feel bad with a score of 62 - lol.

Hi All,

I understand that Cara from BML hangs here on TPT sometimes and something she said in her presentation at GSAS stuck with me. I paraphrase:

We go outside at noon and take a picture. In theory the colors in the photo should be an accurate rendition in the scene photographed. What do we do when we download the picture from our camera? We bring up Photoshop and start "adjusting" the photo to suit our tastes. Why, because a high CRI looks 'harsh' to us.

I think we all have our own opinions of what looks "good" to us; some like more 'reds', some like 'richer greens' some like something else. One isn't better than the other, they are just different based upon each individuals personal taste.
 

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Discussion Starter · #6 · (Edited)
We go outside at noon and take a picture. In theory the colors in the photo should be an accurate rendition in the scene photographed. What do we do when we download the picture from our camera? We bring up Photoshop and start "adjusting" the photo to suit our tastes. Why, because a high CRI looks 'harsh' to us.
That is jut wrong...on many levels. Between auto contrast/saturation adjustments and the odd "pallet" that a Bayer sensor and processing add to a photo very few come out "as is" anyways..CRI has very little to do w/ many manual adjustments. I could easily argue that one is actually compensating to "up" the CRI or to at least return color balance to it.. One of the things pro photographers don't like is the lack of a decent "cri" in LED lights..or a crazy punctated spectrum like fluorescent.. Ther is the fact that sometimes one wants a "standard" that may differ from a "real life" CRI but that is getting way to technical..
NOON light has a different K not so much a different CRI...
and there is tungsten CRI and Daylight CRI and different versions of daylight CRI..;)
POINT is to have all colors and shades represented then add or subtract what you don't want..Easy enough to do w/ LED's..or digital processing..;)

I think we all have our own opinions of what looks "good" to us; some like more 'reds', some like 'richer greens' some like something else. One isn't better than the other, they are just different based upon each individuals personal taste.
Can't argue w/ that..
but one needs to have something in order to understand what it means by removing it.. ;)
I mean how would one understand they don't like a "cyan" look when there is no cyan even present to begin with..???

but it is a lot like the idea that moonlight is not blue..but the point is one should know what moonlight looks like before calling blue "moonlight".. more like my preferred version of moonlight.. ;)
For those lights who's "moonlight" is stuck w/ blue and no adjustments.. well is is just you are stuck w/ it? or you like it over something else? Well no way of knowing is there..;)
On a odder point.. most wouldn't use any "warm tones" for moonlight..since that would really buck "perception" of what moonlight is or feels like. doesn't mean someone wouldn't love it if given the choice now does it..


Which one is personal prefence and which one would many have a choice about???
Having a full CRI light doesn't always mean one can adjust it but the point is mostly there is no 'missing" shade or color..
As I personally progress in my own 'taste' the importance of ind. "colors" is becoming less since I have "personally" found that once all colors are represented in "white" there is less need for those, except as 'special needs" like sunrise/sunset/moonlight or as an "accent"..
OR possibly to tailor plant growth using the morphologic changes due to heavy red or blue influence (certainty a lower priority for most)
If one is stuck w/ one "tone" might as well have that tone balanced in all colors..
As noted you can have high CRI in every "shade" from 2000k to 16000k...
so the main difference to me (and like the difference between the "golden hour" and noon) is more a difference in K than CRI...

MY idea if a more "ideal" light 2 "daylight" channels of 3000/8500k w/ each approaching 100CRI and a "moonlight" RGB chips...........w/ the RGB being multi-point multi-color programming.. i.e red for morning, blue for moonlight period..
YMMV
ALL OPINION BTW...
 
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