Take a photo with a button

Parts in this circuit

Wiring, pin by pin

Red = 5 V, orange = 3.3 V, black = GND, other colours = signals. “Pin” is the position on the 40-pin header; the GPIO number is what the code uses. Power the Pi from a 5.1 V supply and wire with the power off.

Python code (gpiozero)

from picamera2 import Picamera2
from gpiozero import Button, LED
from signal import pause
from time import sleep

cam = Picamera2()
cam.configure(cam.create_still_configuration())
cam.start()
sleep(1)                      # let the camera adjust to the light

shutter = Button(27)
flash = LED(17)
count = 0

def take_photo():
    global count
    count += 1
    flash.on()
    cam.capture_file("photo%d.jpg" % count)
    flash.off()

shutter.when_pressed = take_photo
print("Move the ball, then press the shutter button")
pause()

The same program with RPi.GPIO

import RPi.GPIO as GPIO
from picamera2 import Picamera2
import time

GPIO.setmode(GPIO.BCM)
GPIO.setup(27, GPIO.IN, pull_up_down=GPIO.PUD_UP)   # shutter button to GND
GPIO.setup(17, GPIO.OUT)                            # flash LED

cam = Picamera2()
cam.configure(cam.create_still_configuration())
cam.start()
time.sleep(1)

count = 0
try:
    while True:
        if GPIO.input(27) == 0:          # pressed
            count += 1
            GPIO.output(17, 1)
            cam.capture_file("photo%d.jpg" % count)
            GPIO.output(17, 0)
            while GPIO.input(27) == 0:   # wait until released
                time.sleep(0.02)
        time.sleep(0.02)
finally:
    GPIO.cleanup()

How the code works

• Picamera2() opens the camera. configure() chooses the picture settings and start() switches the camera on.
• sleep(1) gives the camera a moment to set its brightness, like your eyes in a dark room.
• capture_file("photo1.jpg") saves one picture. The counter gives every photo a new name.
• The flash LED is on only while the picture is taken.

Parts to buy

The links open a search on each store, so you see what is in stock today. Check the model, voltage and price before you order.