What do you mean 'visible light'?
Maybe you mean 'useful light'? Once you move from cool-white to neutral-white you won't go back.
Cool-white: too much blue. Warm-white: too much red
Neutral-white: just right:thumbsup:
The outdoor-white seems like an interesting compromise between cool & neutral. Splits the performance difference: R5-cool, R3-neutral, R4-outdoor.
What I don't like is the reduced CRI. Why doesn't Cree show the SPD?
The flux binning determines how much light is produced. So, a R5 will definitely produce more light than a R2. The lumen curve is adjusted to the human eye sensitivity so a lumen of light is a lumen of light regardless of color or mix of colors. The overall brightness is already binned, so that is the perceivable brightness regardless of tint. Our eyes differ from person to person, so some tints or color temperatures will satisfy more than others. It comes down to preference of tint and the application of the light (white wall, indoors, outdoors, etc).
In concept, you are right about determining overall output (in lumens) by finding the area under the entire light frequency curve. However, those graphs are strictly used to show the proportions of colors perceived in each particular emitter color. The relative light output should be used to compare between the exact same color only. Therefore, for example, the graph was adjusted on the cool white so the blue spike peaks at 100%, while the second lump peak for the warm white was adjusted for 100%. I am assuming that if a Q5 bin of warm, neutral, and cool white was compared directly on the same graph, then that second lump (warmer colors) would be about the same for each color (deeper in the reds for the warmer tints), while the blue spike would appear to be very high for the cool white.
So, in the spirit of CPF, try both. Actually, try all three. Even though it is natural in the LED world now that cooler emitters are more efficient, and therefore, brighter, you may prefer the one tint over the other regardless to tint. All three tints are bright and useful, so do not worry about having a useless light afterward.
Cheers,
Tony
The flux binning determines how much light is produced. So, a R5 will definitely produce more light than a R2. The lumen curve is adjusted to the human eye sensitivity so a lumen of light is a lumen of light regardless of color or mix of colors. The overall brightness is already binned, so that is the perceivable brightness regardless of tint. Our eyes differ from person to person, so some tints or color temperatures will satisfy more than others. It comes down to preference of tint and the application of the light (white wall, indoors, outdoors, etc).
In concept, you are right about determining overall output (in lumens) by finding the area under the entire light frequency curve. However, those graphs are strictly used to show the proportions of colors perceived in each particular emitter color. The relative light output should be used to compare between the exact same color only. Therefore, for example, the graph was adjusted on the cool white so the blue spike peaks at 100%, while the second lump peak for the warm white was adjusted for 100%. I am assuming that if a Q5 bin of warm, neutral, and cool white was compared directly on the same graph, then that second lump (warmer colors) would be about the same for each color (deeper in the reds for the warmer tints), while the blue spike would appear to be very high for the cool white.
So, in the spirit of CPF, try both. Actually, try all three. Even though it is natural in the LED world now that cooler emitters are more efficient, and therefore, brighter, you may prefer the one tint over the other regardless to tint. All three tints are bright and useful, so do not worry about having a useless light afterward.
Cheers,
Tony
So, in the spirit of CPF, try both. Actually, try all three. Even though it is natural in the LED world now that cooler emitters are more efficient, and therefore, brighter, you may prefer the one tint over the other regardless to tint. All three tints are bright and useful, so do not worry about having a useless light afterward.
Cheers,
Tony
Cutter has an XPGWHT-01-5B1-R4-0-01 Neutral, but I would hate to spend 12 bucks shipping for only two emitters. Anyone in the US interested in a small group buy?
Did anyone else notice that cutter has it as a neutral (L1)
and its bin # says (01) or outdoor white.
A guess its a typo I am still new to this so I could be wrong too.
I ordered 8 warm whites 3 days ago. Do they produce less light because
of the phosphors coating (thicker)??? Just curious.
Thanks for any help.
"Seems crazy that Cree is in North Carolina and I'd have to go to Australia to get their LED's."
Do you have a suspicion about that?
Regarding the actual spectrum, one can integrate the product of the eye sensitivity with each of the 3 curves and rescale according to bin.
I'd buy via Australia no problem if it wasn't for shipping. Anyone tried the star xpgs at kai? How are they?
There is free shipping at cutter if your order is more than 100$.Cutter has an XPGWHT-01-5B1-R4-0-01 Neutral, but I would hate to spend 12 bucks shipping for only two emitters. Anyone in the US interested in a small group buy?
Seems crazy that Cree is in North Carolina and I'd have to go to Australia to get their LED's.