[Reference] Nichia E17A/E21A (2000K - 6500K, R9050/R9080, color) CCT and tint shots

FYI, we tested all those LEDs at 700ma because that’s the current used for all E21A binning standard (Nichia)

[Clemence]

I don’t have needs for consistent tint. But I want them to have a decent tint at 100lm and above and my 3000K+4000K(d220) Wizard and 3000K d220 non-mixed Wizard give me that. That’s one of the reasons I’m extremely satisfied with it. I use low and medium modes the most and this mix gives a good tint even on low modes.

Eg. a 2x3500K+2x4500K mix at 0.1A/led ~140lm/otl will give a duv of (0,0007−0,0014):2= −0.0007.

are these possibly still an idea to make?. I need a 16mm MCPCB for Carlco 10507. E21A 503.

Yes, I have also a few Astrolux S41 to mod with such a triple.

Guessing that Clemence was busy because he didn’t post message on BLF recently I sent an e-mail asking if he still intend to make this triple E21A MCPCB and he responded :

Thanks. I’ve been wondering where Clemence has been and if he’s okay. I’m glad to hear he got the city light project, since it’s kind of a big deal.

I wish Clemence was working on my city lights with some nichia goodness. Our city lights are probably below 50 cri, or worse

Thanks for the update Tally-Ho :slight_smile: :+1:

[Clemence]

Has anybody tried E21A 3500K quad? How is the tint, how is the light in real life applications? Recently I got my Nichias and I can’t decide what diode combination I should solder 4500k+3500K or 3500k. 3500k looks great according to the tests, but I am afraid that it will be too yellow/orange.

It depends when you want to use it. In my opinion 3500K is as cool as I can handle at night. 4000K is good for night and day.

My E21 quads are kind of blue to the eye.

What temp do your quads have?

I see, so 3500k is closer to neutral white than to something yellow. Could you please describe how 3500k looks indoors at noon? By indoors I mean an ordinary room with a window or two.

I bought (2) 5000K E21A quads from Virence. Actually, they are headlights in my profile pic. I noticed the grass, tomato, cucumber, and other greens in my backyard appeared more blue than green at night when I lit the backyard with them. However, my camera showed them as mostly green. Hmm, now I question my manual CCT setting on the camera at the time… I will check the metadata.

Let me start fresh with the CCT explanation. I have a fixture over my desk that holds 5 standard bulbs. I bought (3) 6-packs of high CRI Hyperikon in 3000K, 4000K, and 5000K. I needed something that would work for day and night in all weather. This room only has a large North-facing window. There are trees behind my house, so light pollution at night isn’t really a thing I deal with.

The 5000K were… industrial. My wife walked in around sunset and instantly disapproved, saying the color was like florescent lights from work. I agreed.
The 4000K felt nice and neutral, day and night. But I do like a little warm in my lights to help me relax in the evening.
The 3000K were a little too warm day and night, but not bothersome.
So I installed (3) 4000K and (2) 3000K into the same fixture. That is an effective CCT of 3600K. It’s perfect day and night. It neither feels warm or cool any time of the day or in any weather.

Color temperature preferences vary by person, and by ambient conditions.

I tend towards warm CCT’s around the house, and especially when it’s fully dark, but when I need extra light working outdoors around sunset, I like to stay closer to 5000K.

If in doubt, I lean towards recommending 4000K as a decent compromise for most conditions and users.

I used to say it varies by person too, but I’m learning it’s more about the conditions the person uses the lights under. You said you work in 5000K, me too for soldering tasks. I put the 5000K in my workbench area. It helps keep my energy up.
I like warm CCT (2700-3000) in the bedroom and bathrooms because I am getting ready for bed at that time.

The ideal bulb would be cool and bright around noon, and dim and warm around midnight. But that’s not how bulbs work, so we choose CCT by the activity we do in the room and when that is.

So I guess to give a more complete answer, if bulbs came is any CCT’s, this is what I think would appeal to the widest audience:

2850K - for the bedrooms (late night)
3600K - for the rest of the home (comfortable all hours of the day)
4700K - for a workbench (a little crispness to increase your energy level without eye strain during the day)

Philips SceneSwitch “Color” bulbs allow this. They’ve got multiple LED CCT’s in them. If you turn the light on-off-on, it will cycle through 3 different color temperatures. They also have what they call “Warm Glow” dimmable bulbs that get warmer as they dim.

And I think their “White Ambiance” smart bulbs can be programmed to automatically vary their CCT depending on the time of day.

I’ve also seen some Eaton recessed light fixtures with selectable CCT’s, but it’s chosen at the time of installation with a switch, so it’s not easy to change.

I would like to check those out, I didn’t have any luck with finding them though.
My only concerns would be if they have good CRI and what the price is.

yes
for me 3500k is too yellow/orange during the day when Im indoors by a north window.

I like 3500k in the evening

during the day I EDC 4500k

my house lights are 3000k

I tried 6500k over a soldering station, but found I prefer 5600k

if I had to pick just one cct for everything
day and night,
working and relaxing,
it would be 4500k

but those are 4 different scenarios and I have 4 different CCTs for that :slight_smile:

Thank you very much. That’s a lot of useful information. I plan to use my quad as an EDC that’s why I am uncertain what CCT I should choose. Maukka’s measurements also add to my doubts, because diodes seem to have lower CCT than it is claimed by the manufacturer and 3500k tends to have the highest CRI overall. (Btw, could somebody explain why?).

LEDs vary within a range of ± 250 cct when they get grouped into CCT bins

I do not believe that it is accurate to say that 3500k has the highest CRI, I cannot verify that information based on the info you have provided.

if you plan to EDC during the day, I would choose 4500k, or even 5000k… some people even prefer 5700k…

but if you keep your question simple, such as is 3500k or 4500k more useful for daytime EDC, I would definitely not suggest the 3500k

3500k is quite warm during the day
it is imo a specialty CCT, for relaxing in the evening