Multiple Photocell Problem (Arduino)?

Hello, I have a problem with using more than 1 photocell. I am using the AnalogReadSerial example to test each one and they are giving me junk. I have tried just one wired to the board and it works fine, but when i wire 4 into a breadboard it gets messy.
                                                                                            Here are some pictures


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jenniferm82 years ago

I'm doing a university project slightly similar to this, is there any chance you could upload your code so I could get a little help with reading the multiple light sensors? Ive got my hand in very soon and my whole set up seems to have stopped working all of a sudden. Hope you can help or you can direct me somewhere to look as I can't seem to find anything similar to mine except yours!

What resistor did you use ?
D5quar3 (author)  steveastrouk4 years ago
1K ohm. I have tried multiple resistor values, and I still get the same problem
Try putting a good 100nf cap across each cds cell, to try to reduce noise. What are you actually seeing coming out?
D5quar3 (author)  steveastrouk4 years ago
I figured it was the 5v and ground rails on my breadboard needed some jumpers, after that I was getting steady numbers.
Libahunt4 years ago
Use a short delay each time before moving on to read next sensor. Something between 2 and 10 milliseconds should be enough.

Explanation about the need for a delay in second reply there: