diff --git a/libraries/AP_Baro/AP_Baro_BMP085.cpp b/libraries/AP_Baro/AP_Baro_BMP085.cpp
index 611fe58885..eefd9c5dad 100644
--- a/libraries/AP_Baro/AP_Baro_BMP085.cpp
+++ b/libraries/AP_Baro/AP_Baro_BMP085.cpp
@@ -56,6 +56,8 @@ extern "C" {
 // is not available to the arduino digitalRead function.
 #define BMP_DATA_READY() (_apm2_hardware?(PINE&0x80):digitalRead(BMP085_EOC))
 
+// oversampling 3 gives highest resolution
+#define OVERSAMPLING 3
 
 // Public Methods //////////////////////////////////////////////////////////////
 bool AP_Baro_BMP085::init( AP_PeriodicProcess * scheduler )
@@ -64,7 +66,6 @@ bool AP_Baro_BMP085::init( AP_PeriodicProcess * scheduler )
 	
 	pinMode(BMP085_EOC, INPUT);	 // End Of Conversion (PC7) input
 
-	oss = 3;					 // Over Sampling setting 3 = High resolution
 	BMP085_State = 0;		 // Initial state
 
 	// We read the calibration data registers
@@ -142,7 +143,7 @@ int32_t AP_Baro_BMP085::get_raw_temp() {
 // Send command to Read Pressure
 void AP_Baro_BMP085::Command_ReadPress()
 {
-	if (I2c.write(BMP085_ADDRESS, 0xF4, 0x34+(oss << 6)) != 0) {
+	if (I2c.write(BMP085_ADDRESS, 0xF4, 0x34+(OVERSAMPLING << 6)) != 0) {
 		healthy = false;
 	}
 }
@@ -163,14 +164,15 @@ void AP_Baro_BMP085::ReadPress()
 		return;
 	}
 
-	RawPress = (((long)buf[0] << 16) | ((long)buf[1] << 8) | ((long)buf[2])) >> (8 - oss);
+	RawPress = (((uint32_t)buf[0] << 16) | ((uint32_t)buf[1] << 8) | ((uint32_t)buf[2])) >> (8 - OVERSAMPLING);
 
-	if(_offset_press == 0){
+	if (_offset_press == 0){
 		_offset_press = RawPress;
 		RawPress = 0;
 	} else{
 		RawPress -= _offset_press;
 	}
+
 	// filter
 	_press_filter[_press_index++] = RawPress;
 
@@ -186,7 +188,6 @@ void AP_Baro_BMP085::ReadPress()
 
 	// grab result
 	RawPress /= PRESS_FILTER_SIZE;
-	//RawPress >>= 3;
 	RawPress += _offset_press;
 }
 
@@ -261,16 +262,16 @@ void AP_Baro_BMP085::Calculate()
 	x1 = (b2 * (b6 * b6 >> 12)) >> 11;
 	x2 = ac2 * b6 >> 11;
 	x3 = x1 + x2;
-	//b3 = (((int32_t) ac1 * 4 + x3)<<oss + 2) >> 2; // BAD
-	//b3 = ((int32_t) ac1 * 4 + x3 + 2) >> 2;  //OK for oss=0
+	//b3 = (((int32_t) ac1 * 4 + x3)<<OVERSAMPLING + 2) >> 2; // BAD
+	//b3 = ((int32_t) ac1 * 4 + x3 + 2) >> 2;  //OK for OVERSAMPLING=0
 	tmp = ac1;
-	tmp = (tmp*4 + x3)<<oss;
+	tmp = (tmp*4 + x3)<<OVERSAMPLING;
 	b3 = (tmp+2)/4;
 	x1 = ac3 * b6 >> 13;
 	x2 = (b1 * (b6 * b6 >> 12)) >> 16;
 	x3 = ((x1 + x2) + 2) >> 2;
 	b4 = (ac4 * (uint32_t) (x3 + 32768)) >> 15;
-	b7 = ((uint32_t) RawPress - b3) * (50000 >> oss);
+	b7 = ((uint32_t) RawPress - b3) * (50000 >> OVERSAMPLING);
 	p = b7 < 0x80000000 ? (b7 * 2) / b4 : (b7 / b4) * 2;
 
 	x1 = (p >> 8) * (p >> 8);
diff --git a/libraries/AP_Baro/AP_Baro_BMP085.h b/libraries/AP_Baro/AP_Baro_BMP085.h
index 8e08965996..06cd3ff1d1 100644
--- a/libraries/AP_Baro/AP_Baro_BMP085.h
+++ b/libraries/AP_Baro/AP_Baro_BMP085.h
@@ -28,14 +28,11 @@ class AP_Baro_BMP085 : public AP_Baro
 
   private:
 	int32_t RawPress;
-	int32_t	_offset_press;
+	int32_t _offset_press;
 	int32_t RawTemp;
 	int16_t Temp;
-	int32_t Press;
-	//int Altitude;
-	uint8_t oss;
+	uint32_t Press;
 	bool _apm2_hardware;
-	//int32_t Press0;  // Pressure at sea level
 
 
     // State machine
@@ -44,9 +41,9 @@ class AP_Baro_BMP085 : public AP_Baro
 	int16_t ac1, ac2, ac3, b1, b2, mb, mc, md;
     uint16_t ac4, ac5, ac6;
 
-	int	 	_temp_filter[TEMP_FILTER_SIZE];
-	int	 	_press_filter[PRESS_FILTER_SIZE];
-	long	_offset_temp;
+	int16_t _temp_filter[TEMP_FILTER_SIZE];
+	int32_t _press_filter[PRESS_FILTER_SIZE];
+	int32_t	_offset_temp;
 
 	uint8_t	_temp_index;
 	uint8_t	_press_index;
diff --git a/libraries/AP_Baro/AP_Baro_BMP085_hil.h b/libraries/AP_Baro/AP_Baro_BMP085_hil.h
index d7dbfd7618..bf121f2f16 100644
--- a/libraries/AP_Baro/AP_Baro_BMP085_hil.h
+++ b/libraries/AP_Baro/AP_Baro_BMP085_hil.h
@@ -17,7 +17,6 @@ public:
 	//int Altitude;
     bool healthy;
 
-	uint8_t oss;
 	bool init(AP_PeriodicProcess * scheduler);
 	uint8_t read();
 	int32_t get_pressure();
@@ -26,7 +25,6 @@ public:
 	int32_t get_raw_pressure();
 	int32_t get_raw_temp();
 	void setHIL(float Temp, float Press);
-	int32_t _offset_press;
 };
 
 #endif //  __AP_BARO_BMP085_HIL_H__