E21A Color Test with surprising result

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WTF
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staticx57 wrote:
Depends, what cell are you using? Quad E21A behind a 10440 would be fine. Behind a high drain 18650 with springs and all bypassed might not.

Haven’t built the light yet. Thinking about converting an old srk style light into a mule using the existing led board.

SKV89
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With and without optic or reflector makes a very big difference in both CCT and tint. Here are two examples with the SST-20 4000K. Bare emitter is always much cooler.

http://budgetlightforum.com/comment/1541829#comment-1541829

http://budgetlightforum.com/comment/1546918#comment-1546918

djozz
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There are just so many variables.

Like the current, and the angle at which you measure the bare led. A diffuser like dcfix will average it somewhat but will still only catch and diffuse less than half of the light. Moreover, a any diffusor causes loss of blue light and warms the tint because of blue scattering more than the other wavelengths. Using optics selects other parts of the light again.

The only way to measure average tint is with an integrating sphere coupled to a spectrometer. It integrates the full 180 degrees of output and the sphere can be characterised by measuring the colour-specific light loss over the spectrum and correct for that. Maukka is the only amateur I know of to have that setup and post results with it.

Joshk
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Update, I got a reflector in the mail yesterday for another project that happens to fit the E21 perfect. The results are much improved.

CIE

Ryzbor
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Did this particular TIR lens, it seems a narrow one, result in a cross pattern in the beam?

virence.com rosy 3500K R9080 Wizard Pro, MF01 Mini 4000K to be modded with FA3 SST20, super rosy 3000K E21A Tiara and super warm 2000K Wizard Pro on it's way

Joshk
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No it looked like a normal beam with a round hotspot.

Ryzbor
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Interesting. Which particular TIR did you use?

virence.com rosy 3500K R9080 Wizard Pro, MF01 Mini 4000K to be modded with FA3 SST20, super rosy 3000K E21A Tiara and super warm 2000K Wizard Pro on it's way

Joshk
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I’m not sure I can reveal my source. It’s a trade secret Silly

Joshk
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I bought the cheapest one on AliExpress for $0.75.
https://www.aliexpress.com/item/32817065402.html?spm=a2g0s.9042311.0.0.6...

Joshk
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I gave the DC fix a try today. Too close, and it doesn’t diffuse well. Too far and it doesn’t catch the warm light. It needs a reflector. I made a 13mm high reflector for it, but the light from the E21 is so concentrated it was still too close. Drr. I’m not sure if I will continue the project, since the E21 hates 2amps anyway.

Joshk
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I tested with all different powers on this new thread:
http://budgetlightforum.com/node/69149

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