I am currently using a TCS3200 RGB color sensor but the sensed values for same color varies with the distance between sensor and color source. How should I calibrate my sensor so as to get values between 0-255 with the varying distance of the color source. my color source is a RGB LED

  • \$\begingroup\$ Can you help me how I can achieve this values in some other way? ThankYou. \$\endgroup\$ – Aayush Asati Mar 21 '18 at 12:59
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    \$\begingroup\$ It isn't a question of calibration. The sensor "sees" more than just your RGB led. The further the led is from the sensor, the less the sensor "sees" the led - the led covers up a smaller part of the field of view of the sensor. \$\endgroup\$ – JRE Mar 21 '18 at 13:27
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    \$\begingroup\$ Sounds like if you can guarantee the color of the background, you might be able to calibrate, but if your background changes, you're probably out of luck. Adding some info about the application might help. \$\endgroup\$ – Selvek Mar 21 '18 at 13:51
  • \$\begingroup\$ If you only have a linear detector with 2 decades say 20dB power and Friis path loss that varies 1-25 cm resulting in > 12dB of variation from similar sources your error is more than 60% of your dynamic range instead of 1 or 2%. I once designed an LED calibration unit with 1% relative accuracy using 6 directional sensors in a box at a 1 m distance. That’s what it took since intensity Vs height and width above emitters for beamwidth was done by a selector switch to DMM. In your case a different method will be needed but at some equidistance!! \$\endgroup\$ – Sunnyskyguy EE75 Mar 21 '18 at 14:01
  • \$\begingroup\$ Describe your color source, in detail, as well as the entire optical setup and surroundings and other sources nearby. Is this source based on an emitter itself or the reflected light from a colored surface? Etc. Every detail matters. \$\endgroup\$ – jonk Mar 21 '18 at 15:18

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