Yuji VTC-series D50 5730-size midpower led tested

Interesting write-up. Thanks.

Dang, the tint and cri look amazing! I have 4 of their 5mm hi cri warm emitters, 2 in my magnified headlight and really like them. I would love to see them make a high power led.

They do make this one :innocent: :

Ok… 5050 size!

When you mentioned you had to buy one hundred I thought to myself that you scored a couple for testing from the manufacturer. I laughed when I read the second post. You bought a hundred. Now that is taking one for the team. Your enthusiasm is commendable. Thanks for the testing.
If you get stuck with a heap of left over leds I’d be happy to donate a few bucks to you for the cause. Cheers.

Those would make a great panel light.

Would those be suitable replacement for Nitecore Tube?

yes, no problem I guess, nice application!

Nice test, djozz.

Interested in 10 or 20 pieces.

I have some Osram high CRI of the same size, and when you use them without optics they’re really wide angled and no (hardly any) tintshift.
Great for a headlamp for close up stuff.

Question:
Is it noticeable that these little buddies have cyan in their spectrum?

:sunglasses:

…a bit pricey though…

10 or 20 pieces is ok.

I think they are great for a close-up headlamp. If you are in improvisation mode you can stick one of these

into one of these

and put that in one of these

You will not notice the cyan, we humans can not see narrow wavelength bands. There has been some discussion on CPF that high CRI leds are somewhat rosy because of the lack of this band and compensating the tint for that is in principle easy but that compromises the CRI.

I would expect that cyan / turquoise coloured objects look more ‘vibrant’ when there’s also cyan in the light source spectrum.

(I’ll PM you shortly.)

These seem great for retrofitting to a magnifying-type desk lamp.

I just did mine the past weekend, using some neutral white 4014 LEDs from Aliex. Nice improvement, the original 5 mm ‘straw-hat’ LEDs were horrible in comparison. The PCB is single-sided and made for through-hole LEDs, but flipping it over and flowing the LEDs to the through-hole pads was not too difficult. 40 LEDs at 20 mA give plenty of light in that setup with no heat.

Now I will have to redo it :slight_smile:

Whoaaa, very nice colour! Now it’s violet die, next is purple (Seoul and Toshiba)
Thanks for testing Djozz!

Hi I joined just to make this post.
They now have 10W COBs in stock, VTC! MOQ just 5.

I love this yuji VTC spectrum by the looks of it.
So I ordered 5 yesterday, Im verry curious!!

but ONLY 450mA?

The thing Im asking myself is, can you amp them up?

Not a lot of info around, no spec sheet…yet?
https://store.yujiintl.com/collections/vtc-series/products/vtc-series-high-cri-cob-led-135l-pack-5-pcs?variant=45426214099

But yeah I am thinking what driver to take, I want a higher current dimming model, so I can overdrive them, but how much?
How far should I go?

Im gonna use big ass heatsinks so…

Anybody any idea? max 700mA? 1050mA? 1400mA??

ciao
Rokus

Just received mine yesterday. Will find a time to test them out. Thanks Jos =))

Sounds like a plan!
Front row here

Don’t expect quantitative tests like Djozz’s or Maukka’s. I will only use my camera, not the best valid test for comparing CRI, but it’s just fun thing to do.

For me it has mainly to do with the max current that is safe to run them cool enough for longer periods on end.

450mA seems like a very low estimate to me!

https://store.yujiintl.com/collections/vtc-series/products/vtc-series-high-cri-cob-led-135l-pack-5-pcs?variant=45426214099#tabs-3

(Talking about the COBs here VTC Series High CRI COB LED - 135L)