change ev calculation and calibration to log(analog reading) and add digital timetable and ev calculation bugfix

calibration/calibration.py

@@ -2,10 +2,15 @@
 import numpy as np
 import csv
 import matplotlib.pyplot as plt
+import math
 
 xcolumn=0 #column with readings
 ycolumn=4 #column with calibration data
-ncoefs=3 #number of coefficients
+ncoefs=4 #number of coefficients
+
+#mit log
+#low (0), coeffs=4,, <2.7,  ab <=2.3 benutzbar
+#high (1), coeffs=5, >2  ab >=1 knapp benutzbar, ab 2 besser
 
 xvalues=[]
 yvalues=[]
@@ -17,9 +22,9 @@ with open('20180413_calibration.csv', 'r') as csvfile:
         xvalue=row[xcolumn]
         yvalue=row[ycolumn]
         if len(xvalue)>0 and len(yvalue)>0 and not firstrow:
-            xvalue=float(xvalue)
+            xvalue=math.log(float(xvalue))
             yvalue=float(yvalue)
-            if yvalue<=4:
+            if yvalue<2.7:
                 #print(""+str(xvalue)+" - "+str(yvalue))
                 xvalues.append(xvalue)
                 yvalues.append(yvalue)
@@ -28,17 +33,26 @@ with open('20180413_calibration.csv', 'r') as csvfile:
     coefs=np.polyfit(xvalues,yvalues,ncoefs) #fit polynomial curve
     print(coefs) #coef 0 is the one with highest polynomial
 
-    xtest=np.arange(max(xvalues)) #x values for test visualization
+    xtest=np.arange(max(xvalues),step=0.001) #x values for test visualization
     ytest=np.polyval(coefs, xtest) #calculate y values with polynomial function
     #ytest=[coefs[3]+coefs[2]*pow(x,1)+coefs[1]*pow(x,2)+coefs[0]*pow(x,3) for x in xtest]
 
-    for i in range(200,4000,10):
+    #for i in range(200,4000,10):
-        yv=np.polyval(coefs, i)
+    #    yv=np.polyval(coefs, i)
-        print(str(i)+";"+str(yv))
+    #    print(str(i)+";"+str(yv))
-    exit()
+    #exit()
 
-    plt.scatter(xvalues,yvalues,s=0.25,c='g') #plot sample data
+    plt.scatter(xvalues,yvalues,s=0.7,c='g') #plot sample data
     plt.plot(xtest,ytest,c='r') #plot approximated curve
     plt.xlabel('LDR Value')
     plt.ylabel('Ev')
+
+    #plt.xlim(0,4096) #ldr
+    plt.ylim(-3,20) #ev
+
+    #limits with lux
+    #plt.xlim(0,4096) #ldr
+    #plt.xlim(0,500) #ldr
+    #plt.ylim(0,1280000) #ev
+    #plt.ylim(0,220) #ev
     plt.show()

lightmeter.ino

@@ -6,7 +6,7 @@
 
 //Letters 5x7 at Size 1
 
-
+#include <math.h> 
 //#include <SPI.h>
 #include <Wire.h>
 #include <Adafruit_GFX.h>
@@ -54,8 +54,10 @@ BH1750 lightMeter;
 //float shuttertimes1[]={1,1.0/2, 1.0/4, 1.0/8, 1.0/15, 1.0/30, 1.0/60, 1.0/125, 1.0/250, 1.0/500, 1.0/1000, 1.0/2000, 1.0/4000, 1.0/8000};
 float shuttertimes1[]={64,32,16,8,4,2,1,1.0/2, 1.0/4, 1.0/8, 1.0/15, 1.0/30, 1.0/60, 1.0/125, 1.0/250, 1.0/500, 1.0/1000, 1.0/2000, 1.0/4000, 1.0/8000};
 #define SHUTTERTIMES1_MAXINDEX 19
-String settingsnameShutterSelectionMode[]={"Analog"}; //names for tables
+float shuttertimes2[]={30,25,20,15,13,10,8,6,5,4,3.2,2.5,2,1.6,1.3,1,0.8,0.6,0.5,0.4,0.3,1.0/4,1.0/5,1.0/6,1.0/8,1.0/10,1.0/13,1.0/15,1.0/20,1.0/25,1.0/30,1.0/40,1.0/50,1.0/60,1.0/80,1.0/100,1.0/125,1.0/160,1.0/200,1.0/250,1.0/320,1.0/400,1.0/500,1.0/640,1.0/800,1.0/1000,1.0/1250,1.0/1600,1.0/2000,1.0/2500,1.0/3200,1.0/4000};
-#define MAXIMUM_SHUTTERSELECTIONMODES 1
+#define SHUTTERTIMES2_MAXINDEX 51
+String settingsnameShutterSelectionMode[]={"Analog","Digital"}; //names for tables
+#define MAXIMUM_SHUTTERSELECTIONMODES 2
 
 float aperaturesFull[]={1,1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32};
 #define APERATURESFULL_MAXINDEX 10
@@ -99,7 +101,7 @@ boolean button_hold_left=false;
 boolean button_hold_center=false;
 boolean button_hold_right=false;
 
-float vbat=0;
+float vbat=100;
 
 struct Settings {
   uint8_t minimumAperatureIndex; //see corresponding aperatures table
@@ -233,6 +235,8 @@ void setup() {
   }
 
   
+
+  
 }
 
 
@@ -427,7 +431,10 @@ void handleInputs()
   */
   
   //Voltage
-  vbat=map(analogRead(PIN_VBAT), 0,3560,0,8200)/1000.0; //180k and 300k voltage divider. 8,4V -> 3,15V=3910
+  float _vbat=map(analogRead(PIN_VBAT), 0,3560,0,8200)/1000.0; //180k and 300k voltage divider. 8,4V -> 3,15V=3910
+  if (_vbat<vbat){
+    vbat=_vbat; //voltage can only decrease
+  }
 
   //LDR
 
@@ -483,28 +490,49 @@ void handleInputs()
     for (float i=1.0/8000;i<32;i*=2){
       Serial.print(i,6);
       Serial.print(" -> ");
-      Serial.print(roundShutter(i,1),6);
+      Serial.print(roundShutter(i,2),6);
       Serial.print(" -- ");
-      Serial.println(reciprocFloat(roundShutter(i,1))); 
+      Serial.println(reciprocFloat(roundShutter(i,2))); 
+    }
     }
     
+    
 
-    Serial.println("calculateShutter at iso 100 f8");
+    Serial.println("calculateShutter at iso 100 f2.8");
-    for (int8_t i=-2;i<18;i++){
+    for (float i=-2;i<18;i+=0.25){
       Serial.print(i);
       Serial.print(" -> ");
-      Serial.println(calculateShutter(i, (uint16_t)100, 8.0),6);
+      float test_calcshutter=calculateShutter(i, (uint16_t)100, 2.8);
+      //Serial.println(test_calcshutter,6);
+
+      float test_showShutter=roundShutter(test_calcshutter,2);
+      Serial.print("rounded Shutter from "); Serial.print(test_calcshutter,6); Serial.print(" to "); Serial.println(test_showShutter,6); //asdf
+      if (test_showShutter>0.25) //check shuttertime
+      { //show full seconds
+        Serial.print("int=");
+        Serial.print(int(test_showShutter));
+        if (test_showShutter-int(test_showShutter)>0){ //has decimals
+          Serial.print(" ,");
+          Serial.print((int)round( (test_showShutter-int(test_showShutter))*10)); //show one decimal
+        }
+        Serial.println("");
+      }else{ //show fraction of a second
+        Serial.print("frac=  1/");
+        int _frac_showShutter = (int) (   (1.0f/( (int)(test_showShutter*1000000) ) )*1000000 );
+        Serial.print(  _frac_showShutter );
+        Serial.println("");
+      }
     }
 
-    Serial.println("calculateAperature at iso 100 1/125s");
+    Serial.println("calculateAperature at iso 100 1/250s");
-    for (int8_t i=-2;i<18;i++){
+    for (float i=-2;i<18;i+=0.25){
       Serial.print(i);
       Serial.print(" -> ");
-      Serial.println(calculateAperature(i, (uint16_t)100, 1.0/125),6);
+      Serial.println(calculateAperature(i, (uint16_t)100, 1.0/250),6);
     }
     
-  }
+  }*/
-  */
+  
 
 
   switch(displaymode){
@@ -625,6 +653,7 @@ void handleInputs_Lightmeter()
 void handleInputs_Settings()
 {
   if ( button_hold_center  ) { //Go to Lightmeter
+    settings_itemActive=false; //deselect item
     displaymode=lightmeter;
   }
 
@@ -733,19 +762,49 @@ float getEV(){
     //double lowev=-0.763427709 + 0.0138031137*analog_low + -0.00000576990095*pow(analog_low,2) + 0.000000000871611285*pow(analog_low,3);
 
     //calibration 20180413
-    double highev=4.76455098 + 0.00961533698*analog_high - 0.00000399325586*pow(analog_high,2) + 0.000000000654378697 *pow(analog_high,3);
+    //polynomial only
-    double lowev=-38.9534785 + 0.310426970*analog_low - 0.000769939297*pow(analog_low,2) + 0.000000639458491*pow(analog_low,3);
+    //double highev=4.76455098 + 0.00961533698*analog_high - 0.00000399325586*pow(analog_high,2) + 0.000000000654378697 *pow(analog_high,3);
+    //double lowev=-38.9534785 + 0.310426970*analog_low - 0.000769939297*pow(analog_low,2) + 0.000000639458491*pow(analog_low,3);
+    
+    
+    double log_low=log(analog_low);
+    //[-2.47999992e+02  5.59942657e+03 -4.74076773e+04  1.78389539e+05  -2.51728845e+05]
+    double lowev=-251728.845 + 178389.539*log_low - 47407.6773*pow(log_low,2) + 5599.42657*pow(log_low,3) - 247.999992*pow(log_low,4);
+    
+    double log_high=log(analog_high);
+    //[7.27310051e-02 -2.02919373e+00  2.23823220e+01 -1.22121768e+02  3.32574527e+02 -3.60445720e+02]
+    double highev=-360.445720 + 332.574527*log_high - 122.121768*pow(log_high,2) + 22.3823220*pow(log_high,3) - 2.02919373*pow(log_high,4) + 0.0727310051*pow(log_high,5);
+
+    /*Serial.print("analog_low="); //asdf
+    Serial.print(analog_low);
+    Serial.print(" log_low=");
+    Serial.print(log_low);
+    Serial.print(" lowev=");
+    Serial.println(lowev);
+
+    Serial.print("analog_high=");
+    Serial.print(analog_high);
+    Serial.print(" log_high=");
+    Serial.print(log_high);
+    Serial.print(" highev=");
+    Serial.println(highev);*/
 
     
   
-    if (lowev>6){
+    if (highev>2){
       _ev=highev;
-    }else if(lowev<4){
+      Serial.println("using high ev");
+    }else if(lowev<1){
       _ev=lowev;
+      Serial.println("using low ev");
     }else{ //mix of both
-      float mix=min(1.0, max(0.0,(lowev-4)/(6-4))); //0 to 1, 0-> use only lowev, 1-> use only highev
+      float mix=min(1.0, max(0.0,(lowev-1)/(2-1))); //0 to 1, 0-> use only lowev, 1-> use only highev
       _ev=lowev*(1-mix)+highev*mix;
+      Serial.print("mixing mix=");
+      Serial.println(mix);
     }
+    Serial.print("EV=");
+    Serial.println(_ev);
   }else if (meteringmode == METERINGMODE_INCIDENT){ //### INCIDENT
     _ev = luxToEv(incident*INCIDENT_CORRECTION_FACTOR);
   }
@@ -781,7 +840,7 @@ double luxToEv(uint16_t lux){
   return log (lux/2.5) / log (2);
 }
 
-float calculateShutter(float pEv, uint16_t pIso, uint16_t pAperature) //returns calculated Shutter speed given Ev, ISO and Aperature
+float calculateShutter(float pEv, uint16_t pIso, float pAperature) //returns calculated Shutter speed given Ev, ISO and Aperature
 {
   //EV = log2 ( 100* Aperature^2 / (ISO * Time ))
   //100* Aperature^2 / (2^EV * ISO) =  Time
@@ -802,6 +861,9 @@ float roundShutter(float pShutter, uint8_t pMethod) //round shutter to typical v
   case 1: //
       return shuttertimes1[_index];
     break;
+  case 2: //
+      return shuttertimes2[_index];
+    break;
   }
 }
 
@@ -915,6 +977,9 @@ void changeShutter(int8_t pchange){ //pchange>0 means more light exposure (brigh
     case 1:
         _maximumShutterIndex=sizeof(shuttertimes1)/sizeof(float);
       break;
+    case 2:
+        _maximumShutterIndex=sizeof(shuttertimes2)/sizeof(float);
+      break;
   }
   
   if (!( -pchange<0 && _newShutterIndex==0)){ //changed value would not yield negative index
@@ -927,6 +992,9 @@ void changeShutter(int8_t pchange){ //pchange>0 means more light exposure (brigh
     case 1: //
         setShutter=shuttertimes1[_newShutterIndex];
       break;
+    case 2: //
+        setShutter=shuttertimes2[_newShutterIndex];
+      break;
   }
 }
 uint8_t findShutterIndex(float pShutter,uint8_t pMethod) //find index of closest aperature from given aperature tables (pMethod
@@ -940,6 +1008,9 @@ uint8_t findShutterIndex(float pShutter,uint8_t pMethod) //find index of closest
     case 1:
         _maxindexpossible=SHUTTERTIMES1_MAXINDEX;
       break;
+    case 2:
+        _maxindexpossible=SHUTTERTIMES2_MAXINDEX;
+      break;
   }
 
   
@@ -955,6 +1026,9 @@ uint8_t findShutterIndex(float pShutter,uint8_t pMethod) //find index of closest
     case 1:
         _minDistance=abs(pShutter - shuttertimes1[_index]);
       break;
+    case 2:
+        _minDistance=abs(pShutter - shuttertimes2[_index]);
+      break;
     }
     _index++; //next
   }
@@ -1081,7 +1155,7 @@ void updateDisplay_Lightmeter() //Lightmeter display
   display.setCursor(xpos_shutter,ypos_shutter); 
   float _showShutter=roundShutter(showShutter,userSettings.shutterSelectionMode);
   //Serial.print("rounded Shutter from "); Serial.print(showShutter); Serial.print(" to "); Serial.println(_showShutter); //asdf
-  if (_showShutter>=1) //check time
+  if (_showShutter>0.25) //check shuttertime
   { //show full seconds
     display.print(int(_showShutter));
     if (_showShutter-int(_showShutter)>0){ //has decimals
@@ -1118,7 +1192,10 @@ void updateDisplay_Lightmeter() //Lightmeter display
   
 
   //EV Scale
-  uint8_t _startev=2; //first ev to display, 13 ev values can fit on screen
+  int8_t _startev=-5; //first ev to display, 13 ev values can fit on screen
+  if (ev>2){
+    _startev=2;
+  }
   if (ev>13){
     _startev=5+ev-13;
   }
@@ -1134,7 +1211,7 @@ void updateDisplay_Lightmeter() //Lightmeter display
   display.drawLine(THIRDEVLINEDISTANCE,0,THIRDEVLINEDISTANCE,0,WHITE); //first third line
   display.drawLine(THIRDEVLINEDISTANCE+THIRDEVLINEDISTANCE,0,THIRDEVLINEDISTANCE+THIRDEVLINEDISTANCE,0,WHITE); //second third line
   for (uint8_t _fullevline=1;_fullevline<=13;_fullevline++){
-    uint8_t _current_evvalue = _fullevline+_startev;
+    int8_t _current_evvalue = _fullevline+_startev;
     uint8_t _xpos_center_evtext = _fullevline*FULLEVLINEDISTANCE; //center of current ev line x pos
     display.drawLine(_xpos_center_evtext,0,_xpos_center_evtext,2,WHITE);
     display.drawLine(_xpos_center_evtext+THIRDEVLINEDISTANCE,0,_xpos_center_evtext+THIRDEVLINEDISTANCE,0,WHITE);
@@ -1182,9 +1259,9 @@ void updateDisplay_Lightmeter() //Lightmeter display
   //DEBUG Message
   display.setTextSize(1);
   display.setCursor(xpos_debug,ypos_debug);
-  /*display.print(vbat);
+  display.print(vbat,2);
   display.print("V ");
-  display.print("Ev=");
+  /*display.print("Ev=");
   display.print(ev);
   display.print(" |");
   display.print(incident);*/