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I bought some LEDs on Amazon and uploaded charts showing the wavelength distribution. The LEDs were awful and the charts made it very clear why. Amazon deleted my review and the item currently has 5 stars.

The best lights I have are some warm white LED strips from eBay. I glued them to the top of my workbench (it's a desk under some shelves basically) and it is a joy to work there. I measured them and they are pretty close to daylight in terms of CRI, something like 93 if I recall correctly.

The only thing that makes me unhappy is the current state of LED strip driving. I have a device that takes 120VAC and turns it into 12V for the light strips. It "interprets" the output of a triac dimmer in front of it to PWM the LEDs. Very wasteful and stupid, but there are no constant-current drivers that just let you use something to adjust the current output unless you build your own. (A friend of mine did just that; the lights are amazing.) PWM naturally causes the cheap capacitors in the DC/DC converter to make noise, so I pretty much never dim them.




Did the CRI for the LEDs you bought match that which was listed or did they even have a CRI stated? I'm willing to spend extra for high CRI but so much junk on Amazon outright lies about being UL listed, it wouldn't surprise me if they started lying about CRI once they realize it is a selling point.


Yeah, they claimed a CRI of 91 but it was closer to 70, I think. (Measured with ArgyllCMS and a Colormunki Photo.)

You could tell it was wrong just by looking. It wasn't a measurement that only appeared by looking at it with expensive equipment; you turned the lights on and instantly though "this is completely unusable". I only measured it to see how bad it was.




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