Computing the response time of an LDR

Hello
I’m new to the forum and also Arduino. I do not yet own a Arduino board, but I have this project, where I need to determine the response time of LDRs. I have stumbled upon this:

and this is basically what I want to do, but there’s little info given and the hardware isn’t available it seems. Would it be possible to set this up with an Arduino board, and how heavy would the coding be?

In advance thanks
Erik

Why aim at hardware not available?
Please post the essential facts here. I don't spend time investigating an entire project like that.

A 16 MHz system clock Ardiuno can certainly take analogRead() samples fast to record a 47 Hz wave.
Say you took a sample every 1mS, at 1000 Hz, that would be 20 samples of a 50 Hz signal, and a few more 47 Hz.
A 328P based board (Uno, Promini, Nano), has 2048 bytes of SRAM, and analogRead() returns 2 bytes, so you could capture ~ 1 seconds worth.
Jump to a 1284P based board, with 16K SRAM, and you can capture ~8 seconds worth.

void loop(){
  if (x<5000){ // 5000 samples
    timeNow = micros();
    if (timeNow - timeBefore)>= 1000){ // 1mS sample rate
    timeBefore = timeNow; // set up for next time period
    x=x+1;
    dataArray[x] = analogRead(A0);
    }
  }
  Serial.println("done");
}

So something like that to start, then decide what to do with the data.
Maybe send to a PC for processing, display on a screen, etc.

The hardware would certainly be available if you really want to do the experiment. What is the problem?
Paul

The Arduino ADC can be programmed to sample at tens to hundreds of kHz, which is more than fast enough to fully capture the LDR lag.

To do the linked experiment with an Arduino would take an LED, an LDR and two resistors, one to limit the LED current, and the other to make a voltage divider with the LDR.

Thanks for all the answers.

#1 - I should have written "not readily available" as I haven't been able to find the SEELablet available anywhere. What I would like to do, is to plot the resistance reading against time for a LDR exposed to a blinking light source. In that way I hope to be able to characterize LDRs and sort them according the their response time.

#2 - 1 second should be enough, I hope, the LDRs response should be below 50ms. Is the 1284P board an add on board for the Arduino Uno? And yes I'll transfer the data to a pc and use the plotted data for comparison.

#3 Well there's no problem other than I haven't been able to find the SEELablet anywhere, and I thought it would be easier to get help using the Arduino, as it is readily available, but the linked example using the SEELablet was the only example I could find that did exactly what I would like to do.

#4 The ADC is that incorporated in the Uno already or is it an addon?

In advance thanks
Erik

All Arduinos have an ADC, to my knowledge.

Time to buy an Arduino and get some hands-on experience! Google "arduino ldr" or "arduino light sensor" for tutorials.

Thanks, will do.

Don't get a "UNO" (genuine or clone). Inconvenient form factor.

Get a Nano. In fact, get two as that allows more flexibility. They can be used with breadboards, or "terminal adapters" or with stripboard for decent soldered assembly.

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