WTB: Calibration lights

Buy / Sell Want to Buy
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Looking for a calibration light or two for a sphere from someone who already has a calibrated sphere/tube. Ideally reasonably cheap and 18650 or 21700. Ideally a low power (500-1000lm?) one and a higher powered one (5k lm?) but I’m not sure exactly what are sensible values, if I was e.g. looking to test maybe a 250-30,000lm range. Fine to pay including the cost of the light itself for you to order, or to order to you.

Also, a question for someone who knows more about sphere design than me: If I calibrated using a less powerful light, then tested a more powerful regulated light (M44, X75, etc.) then would that reading then be valid to use as calibration for a larger sphere, or is there too much generation loss?

1 Thank
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I found a veml7700 to be inaccurate in my DIY lumen tube when 1,000+ lumens so I swapped it with a tsl2591 sensor. Calibrated with a maukka light. A large sphere may be better at integrating light.

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If you can’t find one you could try this : Beam Profiles V3 released: an alternative to spheres and white wall shots
It’s a way to integrate a light, which can be used as calibration light in a sphere.

2 Thanks
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Where are you located? i have a calibration light from Maukka i am not using anymore

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The US. I honestly have no idea how much those lights go for, how much were you looking for? Feel free to DM.