can you help me. I've been making my solar tracker with R1 is my LDR, R2 is fixed 1K resistor... It can't track the sun very well, but in the dark room and I flashed it with my flash light, it track it very well...

I'm confused

Sorry if my English not that good

  • Sunlight is very diffuse. It can't see much difference between direct sunlight and ambient sunlight. – Majenko Sep 15 '18 at 18:47
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    I've seen people put the LDR inside a pipe, so only light directly in front of it is seen. – Gerben Sep 15 '18 at 18:53
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    It might also be better to use a photo-diode or phototransitor that senses in the IR spectrum, instead of an LDR. – Gerben Sep 15 '18 at 18:56
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    This video shows a DIY system using 4 LDRs youtube.com/watch?v=_6QIutZfsFs – VE7JRO Sep 16 '18 at 18:38

This is because your LDR catches reflected sunlight from the ground and thinks that it is actually a sun...

Maybe you could install few LDRs and compare their values. The LDR with highest value is looking at sun others are just receiving reflected light.

Why not just adjust sensitivity of single LDR to filter reflected light and react only to direct sunlight? Because intensity of the sunlight will vary during the day, and if you adjust it in the midday it may not react to afternoon's sunlight at all. If you adjust it in the evening it may react even to reflected light in the midday.

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