diff --git a/Motorized_Focus_Camera/python/Motorized_Focus_Camera_Preview.py b/Motorized_Focus_Camera/python/Motorized_Focus_Camera_Preview.py
index 6122e4f..10fcebc 100644
--- a/Motorized_Focus_Camera/python/Motorized_Focus_Camera_Preview.py
+++ b/Motorized_Focus_Camera/python/Motorized_Focus_Camera_Preview.py
@@ -2,8 +2,9 @@
 import os
 import time
 import sys
-import thread
+import _thread as thread
 from ctypes import *
+
 keyboard = CDLL('./lib/libarducam_keyboard.so')
 arducam_vcm =CDLL('./lib/libarducam_vcm.so')
 UP      = 1
@@ -11,8 +12,11 @@
 SAVE    = 115
 focus_val = 512;
 step = 10
+
+CAMERA_NUMBER = 0
+
 def run_camera(name):
-    os.system("raspistill -t 0")
+    os.system(f"raspistill -t 0 -cs {CAMERA_NUMBER}")
 if __name__ == "__main__":
     thread.start_new_thread(run_camera, ("run_camera",))
     #vcm init
@@ -22,6 +26,8 @@ def run_camera(name):
    # preview=camera.start_preview()
     #set windows size
    # preview.window=(0,0,800,600)
+
+    arducam_vcm.choose_channel(CAMERA_NUMBER)
     print("Please press up and down to adjust focus.")
     while True:
         keyVal = keyboard.processKeyEvent()
diff --git a/Motorized_Focus_Camera/python/multi_cameras_auto_focus.py b/Motorized_Focus_Camera/python/multi_cameras_auto_focus.py
index 2cf1fa5..3dd47cf 100644
--- a/Motorized_Focus_Camera/python/multi_cameras_auto_focus.py
+++ b/Motorized_Focus_Camera/python/multi_cameras_auto_focus.py
@@ -1,133 +1,131 @@
 import cv2 #sudo apt-get install python-opencv
-import numpy as py
 import os
 import time
 from ctypes import *
-cameraNum = 2
+
 #load arducam shared object file
 arducam_vcm= CDLL('./lib/libarducam_vcm.so')
 try:
-	import picamera
-	from picamera.array import PiRGBArray
+    import picamera
+    from picamera.array import PiRGBArray
 except:
-	sys.exit(0)
-	
+    sys.exit(0)
+        
 def focusing(val):
-        arducam_vcm.vcm_write(val)
-        #print("focus value: {}".format(val))
-	
+    arducam_vcm.vcm_write(val)
+    #print("focus value: {}".format(val))
+        
 def sobel(img):
-	img_gray = cv2.cvtColor(img,cv2.COLOR_RGB2GRAY)
-	img_sobel = cv2.Sobel(img_gray,cv2.CV_16U,1,1)
-	return cv2.mean(img_sobel)[0]
+    img_gray = cv2.cvtColor(img,cv2.COLOR_RGB2GRAY)
+    img_sobel = cv2.Sobel(img_gray,cv2.CV_16U,1,1)
+    return cv2.mean(img_sobel)[0]
 
 def laplacian(img):
-	img_gray = cv2.cvtColor(img,cv2.COLOR_RGB2GRAY)
-	img_sobel = cv2.Laplacian(img_gray,cv2.CV_16U)
-	return cv2.mean(img_sobel)[0]
-	
+    img_gray = cv2.cvtColor(img,cv2.COLOR_RGB2GRAY)
+    img_sobel = cv2.Laplacian(img_gray,cv2.CV_16U)
+    return cv2.mean(img_sobel)[0]
+        
 
 def calculation(camera):
-	rawCapture = PiRGBArray(camera) 
-	camera.capture(rawCapture,format="bgr", use_video_port=True)
-	image = rawCapture.array
-	rawCapture.truncate(0)
-	return laplacian(image)
-	
+    rawCapture = PiRGBArray(camera) 
+    camera.capture(rawCapture,format="bgr", use_video_port=True)
+    image = rawCapture.array
+    rawCapture.truncate(0)
+    return laplacian(image)
+        
 
 if __name__ == "__main__":
     #vcm init
-  arducam_vcm.vcm_init()
+    arducam_vcm.vcm_init()
     #open camera
-  camera = picamera.PiCamera()
-	
-  #open camera preview
-  camera.start_preview()
-	#set camera resolution to 640x480(Small resolution for faster speeds.)
-  camera.resolution = (640, 480)
-  time.sleep(0.1)
-  print("Start focusing 1")
-  max_index = 10
-  max_value = 0.0
-  last_value = 0.0
-  dec_count = 0
-  focal_distance = 10
-	#choose cmaera A
-  arducam_vcm.choose_channel(0)
-  while True:
-	    #Adjust focus
-		focusing(focal_distance)
-		#Take image and calculate image clarity
-		val = calculation(camera)
-		#Find the maximum image clarity
-		if val > max_value:
-			max_index = focal_distance
-			max_value = val	
-		#If the image clarity starts to decrease
-		if val < last_value:
-			dec_count += 1
-		else:
-			dec_count = 0
-		#Image clarity is reduced by six consecutive frames
-		if dec_count > 6:
-			break
-		last_value = val
-		#Increase the focal distance
-		focal_distance += 15
-		if focal_distance > 1000:
-			break
+    camera = picamera.PiCamera()
+          
+    #open camera preview
+    camera.start_preview()
+    #set camera resolution to 640x480(Small resolution for faster speeds.)
+    camera.resolution = (640, 480)
+    time.sleep(0.1)
+    print("Start focusing 1")
+    max_index = 10
+    max_value = 0.0
+    last_value = 0.0
+    dec_count = 0
+    focal_distance = 10
+    #choose cmaera A
+    arducam_vcm.choose_channel(0)
+    while True:
+        # adjust focus
+        focusing(focal_distance)
+        #Take image and calculate image clarity
+        val = calculation(camera)
+        #Find the maximum image clarity
+        if val > max_value:
+            max_index = focal_distance
+            max_value = val     
+        #If the image clarity starts to decrease
+        if val < last_value:
+            dec_count += 1
+        else:
+            dec_count = 0
+        #Image clarity is reduced by six consecutive frames
+        if dec_count > 6:
+            break
+        last_value = val
+        #Increase the focal distance
+        focal_distance += 15
+        if focal_distance > 1000:
+            break
     #Adjust focus to the best
-  focusing(max_index)
-  time.sleep(1)
-	#set camera resolution to 2592x1944
-  camera.resolution = (1920,1080)
-	#save image to file.
-  camera.capture("test_A.jpg")
-  print("max index = %d,max value = %lf" % (max_index,max_value))
-  print("Start focusing 2")
-  max_index = 10
-  max_value = 0.0
-  last_value = 0.0
-  dec_count = 0
-  focal_distance = 10
-  camera.resolution = (640, 480)
-	#choose cmaera A
-  arducam_vcm.choose_channel(1)
-  while True:
-	    #Adjust focus
-		focusing(focal_distance)
-		#Take image and calculate image clarity
-		val = calculation(camera)
-		#Find the maximum image clarity
-		if val > max_value:
-			max_index = focal_distance
-			max_value = val	
-		#If the image clarity starts to decrease
-		if val < last_value:
-			dec_count += 1
-		else:
-			dec_count = 0
-		#Image clarity is reduced by six consecutive frames
-		if dec_count > 6:
-			break
-		last_value = val
-		#Increase the focal distance
-		focal_distance += 15
-		if focal_distance > 1000:
-			break
+    focusing(max_index)
+    time.sleep(1)
+    #set camera resolution to 2592x1944
+    camera.resolution = (1920,1080)
+    #save image to file.
+    camera.capture("test_A.jpg")
+    print("max index = %d,max value = %lf" % (max_index,max_value))
+    print("Start focusing 2")
+    max_index = 10
+    max_value = 0.0
+    last_value = 0.0
+    dec_count = 0
+    focal_distance = 10
+    camera.resolution = (640, 480)
+    #choose cmaera A
+    arducam_vcm.choose_channel(1)
+    while True:
+        # adjust focus
+        focusing(focal_distance)
+        #Take image and calculate image clarity
+        val = calculation(camera)
+        #Find the maximum image clarity
+        if val > max_value:
+            max_index = focal_distance
+            max_value = val     
+        #If the image clarity starts to decrease
+        if val < last_value:
+            dec_count += 1
+        else:
+            dec_count = 0
+        #Image clarity is reduced by six consecutive frames
+        if dec_count > 6:
+            break
+        last_value = val
+        #Increase the focal distance
+        focal_distance += 15
+        if focal_distance > 1000:
+            break
+    
     #Adjust focus to the best
-  focusing(max_index)
-  time.sleep(1)
-	#set camera resolution to 2592x1944
-  camera.resolution = (1920,1080)
-	#save image to file.
-  camera.capture("test_B.jpg")
-  print("max index = %d,max value = %lf" % (max_index,max_value))
-  
- 
-	#while True:
-	#	time.sleep(1)
-  camera.stop_preview()
-  camera.close()
-		
-	
+    focusing(max_index)
+    time.sleep(1)
+    #set camera resolution to 2592x1944
+    camera.resolution = (1920,1080)
+    #save image to file.
+    camera.capture("test_B.jpg")
+    print("max index = %d,max value = %lf" % (max_index,max_value))
+    
+    
+    #while True:
+    #time.sleep(1)
+    camera.stop_preview()
+    camera.close()