ESP32 can't handle trigger signal to take photo

The problem is, the following code doesn't work. If I am not using the if to check if there is a signal at GPIO 16, then the code is working. I'm using a ESP32-CAM module. It doesn't save a picture to the SD card.

If I leave the if (digitalRead(16)) away, the code will save every loop a picture to the SD-Card.

/*********
  Rui Santos
  Complete project details at https://RandomNerdTutorials.com/esp32-cam-pir-motion-detector-photo-capture/
 
  IMPORTANT!!!
   - Select Board "AI Thinker ESP32-CAM"
   - GPIO 0 must be connected to GND to upload a sketch
   - After connecting GPIO 0 to GND, press the ESP32-CAM on-board RESET button to put your board in flashing mode
 
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files.
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
*********/
 
#include "esp_camera.h"
#include "Arduino.h"
#include "FS.h"                // SD Card ESP32
#include "SD_MMC.h"            // SD Card ESP32
#include "soc/soc.h"           // Disable brownour problems
#include "soc/rtc_cntl_reg.h"  // Disable brownour problems
#include "driver/rtc_io.h"
#include <EEPROM.h>            // read and write from flash memory
// define the number of bytes you want to access
#define EEPROM_SIZE 1
 
RTC_DATA_ATTR int bootCount = 0;

// Pin definition for CAMERA_MODEL_AI_THINKER
#define PWDN_GPIO_NUM     32
#define RESET_GPIO_NUM    -1
#define XCLK_GPIO_NUM      0
#define SIOD_GPIO_NUM     26
#define SIOC_GPIO_NUM     27
#define Y9_GPIO_NUM       35
#define Y8_GPIO_NUM       34
#define Y7_GPIO_NUM       39
#define Y6_GPIO_NUM       36
#define Y5_GPIO_NUM       21
#define Y4_GPIO_NUM       19
#define Y3_GPIO_NUM       18
#define Y2_GPIO_NUM        5
#define VSYNC_GPIO_NUM    25
#define HREF_GPIO_NUM     23
#define PCLK_GPIO_NUM     22
 
int pictureNumber = 0;

void setup() {
  WRITE_PERI_REG(RTC_CNTL_BROWN_OUT_REG, 0); //disable brownout detector
  Serial.begin(115200);
 
  Serial.setDebugOutput(true);
 
  camera_config_t config;
  config.ledc_channel = LEDC_CHANNEL_0;
  config.ledc_timer = LEDC_TIMER_0;
  config.pin_d0 = Y2_GPIO_NUM;
  config.pin_d1 = Y3_GPIO_NUM;
  config.pin_d2 = Y4_GPIO_NUM;
  config.pin_d3 = Y5_GPIO_NUM;
  config.pin_d4 = Y6_GPIO_NUM;
  config.pin_d5 = Y7_GPIO_NUM;
  config.pin_d6 = Y8_GPIO_NUM;
  config.pin_d7 = Y9_GPIO_NUM;
  config.pin_xclk = XCLK_GPIO_NUM;
  config.pin_pclk = PCLK_GPIO_NUM;
  config.pin_vsync = VSYNC_GPIO_NUM;
  config.pin_href = HREF_GPIO_NUM;
  config.pin_sscb_sda = SIOD_GPIO_NUM;
  config.pin_sscb_scl = SIOC_GPIO_NUM;
  config.pin_pwdn = PWDN_GPIO_NUM;
  config.pin_reset = RESET_GPIO_NUM;
  config.xclk_freq_hz = 20000000;
  config.pixel_format = PIXFORMAT_JPEG;


  if(psramFound()){
    config.frame_size = FRAMESIZE_UXGA; // FRAMESIZE_ + QVGA|CIF|VGA|SVGA|XGA|SXGA|UXGA
    config.jpeg_quality = 10;
    config.fb_count = 2;
  } else {
    config.frame_size = FRAMESIZE_SVGA;
    config.jpeg_quality = 12;
    config.fb_count = 1;
  }
 
  // Init Camera
  esp_err_t err = esp_camera_init(&config);
  if (err != ESP_OK) {
    Serial.printf("Camera init failed with error 0x%x", err);
    return;
  }
 
  Serial.println("Starting SD Card");
 
  delay(500);
  if(!SD_MMC.begin()){
    Serial.println("SD Card Mount Failed");
    //return;
  }
 
  uint8_t cardType = SD_MMC.cardType();
  if(cardType == CARD_NONE){
    Serial.println("No SD Card attached");
    return;
  }
   
  camera_fb_t * fb = NULL;
 
  
  // initialize EEPROM with predefined size
  EEPROM.begin(EEPROM_SIZE);
  
  
 pinMode(16, INPUT);
  
} 
 
void loop() {
  if((digitalRead(16)))
  {
    fotomachen();
  }
  delay(1000);

}

void fotomachen(){
camera_fb_t * fb = NULL;
  
  // Take Picture with Camera
  fb = esp_camera_fb_get();  
  if(!fb) {
    Serial.println("Camera capture failed");
    return;
  }
  
pictureNumber = EEPROM.read(0) + 1;
 
  // Path where new picture will be saved in SD Card
  String path = "/picture" + String(pictureNumber) +".jpg";
 
  fs::FS &fs = SD_MMC;
  Serial.printf("Picture file name: %s\n", path.c_str());
 
  File file = fs.open(path.c_str(), FILE_WRITE);
  if(!file){
    Serial.println("Failed to open file in writing mode");
  }
  else {
    file.write(fb->buf, fb->len); // payload (image), payload length
    Serial.printf("Saved file to path: %s\n", path.c_str());
    EEPROM.write(0, pictureNumber);
    EEPROM.commit();
  }
  file.close();
  esp_camera_fb_return(fb);
}