TSL2561 - Light Sensor Question
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TSL2561 - Light Sensor Question

by MagicJ on Sat Nov 03, 2012 8:34 pm

Individual readings with this sensor seem to max out at around 4935 - is this a limitation with the sensor or with the sketch?
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Re: TSL2561 - Light Sensor Question

by adafruit_support_bill on Sun Nov 04, 2012 5:51 am

Are you reading luminosity or Lux? Post your sketch.
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Re: TSL2561 - Light Sensor Question

by MagicJ on Wed Nov 07, 2012 5:21 am

Hi

I am using the sketch as per your tutorial available hear http://learn.adafruit.com/tsl2561/

I am reading both luminosity and calculating the lux.

I note that these diodes were designed to measure ambient light - my project is using one of these sensors to measure the light from 3w led's but I also have the same problem in sunlight.

Unfortunately, both the IR and the Full Spectrum max out at around the 4935 figure, with the result that the visible light reduces to zero - as the lux is primarily dependant on the visible light it also reduces to zero.

I also found a reference to the same problem here http://itp.nyu.edu/physcomp/sensors/Rep ... uitTSL2561

Cheers
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Re: TSL2561 - Light Sensor Question

by adafruit_support_bill on Wed Nov 07, 2012 7:12 am

The calculations in the library follow the recommended implementation in the data sheet pretty much verbatim. The example sketch is using the shortest integration time. Have you tried changing it to 101 or 402 MS?
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