diff --git a/stm-firmware/.gitignore b/stm-firmware/.gitignore
index cfdd888..1e70134 100644
--- a/stm-firmware/.gitignore
+++ b/stm-firmware/.gitignore
@@ -14,3 +14,4 @@ reflow-controller.includes
 *.includes
 *.config
 *.files
+*.user.*
diff --git a/stm-firmware/adc-meas.c b/stm-firmware/adc-meas.c
index 4a9f0e3..816b993 100644
--- a/stm-firmware/adc-meas.c
+++ b/stm-firmware/adc-meas.c
@@ -216,7 +216,7 @@ void adc_pt1000_get_resistance_calibration(float *offset, float *sensitivity_dev
 static inline float adc_pt1000_apply_calibration(float raw_resistance)
 {
 	if (calibration_active)
-		return pt1000_res_raw_lf * (1.0f + pt1000_sens_dev) + pt1000_offset;
+        return (raw_resistance - pt1000_offset) * (1.0f + pt1000_sens_dev);
 	else
 		return raw_resistance;