Nodemcu V3 capacitive sensor only senses touch not proximity

Other Hardware Sensors
1

Hello,

I'm quite new to IoT platforms.

I'm trying to make a capacitive sensor that could detect my hand from at least a centimeter.

I'm using Nodemcu V3 and Capacitive Sensing Library by Paul Badger.

I've connected D1 through 10Mohm resistor to copper foil and D2 to the same piece of copper foil (photo below).

4160×3120 1.68 MB

And here's my code:

#include <CapacitiveSensor.h>
CapacitiveSensor   cs = CapacitiveSensor(D1,D2);        

void setup()                    
{
   cs.set_CS_AutocaL_Millis(0xFFFFFFFF);     
   Serial.begin(9600);
}

void loop()                    
{
    long total =  cs.capacitiveSensor(30);          
    Serial.println(total);                   
    delay(10);
}

The serial monitor shows -2 unless I touch the foil when it shows around 15k.

I am unable to read any capacitance in any other case, even if my hand is few milimeters away from the foil...

Could you help me solve this problem?